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Synaptic delay

A 0.2-0.5 msec delay occurs between the arrival of the action potential at the synaptic terminal and the effect on the postsynaptic membrane

nerve; axons

A ___ is a cordlike organ composed of numerous ___.

Distingusish between a pump and a channel, and identify the pumps and channels located along the entire neuron plasma membrane.

A pump moves susbstances against a concentration gradiant and usually requires energy. The plasma membrane of neurons contains both NA+ and K+ pumps and Ca2+ pumps. Channels provide the means to move a substance down (with) it's concentration gradiant. Neurons contain the following types of channels: Leak - always open, continuous diffusion of a a specific type of ion from a region of high to low contenctration. Examples are NA+ leak channels and K+ leak channels. Chemically gated - normally closed. Open in response to binding of a neurotransmitter. Voltage gated - normally closed but open in response to changes in electrical charge (potential) across the PM

electroencephalogram (EEG)

A record of brain waves - Brain waves generated by neurons close to the brain surface, mainly neurons in the cerebral cortex, can be detected by sensors called electrodes placed on the forehead and scalp.

A reflex arc always includes a(n) __________. sensory receptor efferent axon afferent axon A reflex arc always includes all of these structures.

A reflex arc always includes all of these structures.

contralateral

A reflex where the sensory input and motor output are on opposite sides of the spinal cord is called a(n) _____ reflex arc.

Synapse

A specialized site where the neuron communicates with another cell

Which of the following is a function of the thyroid gland? A) maturation of the nervous system B) control storage of lipids C) decrease the rate of energy release from carbohydrates D) inhibit growth in children

A) maturation of the nervous system

The adrenal hormone aldosterone belongs to a category of cortical hormones called A) mineralocorticoids B) glucocorticoids C) sex hormones D) anabolic hormones

A) mineralocorticoids

A major difference between steroid and other types of hormones is A) steroid hormones are lipid soluble B) amines tend to form a receptor-hormone complex that is active within the nucleus of the cell C) receptor sites for steroid hormones are both a receptor site and an activity site D) receptors for steroid hormones are found in the cell membrane

A) steroid hormones are lipid soluble

What 2 things are required in order to visualize near objects?

A. Convergence- turnings inward of eyes (medial rectus muscles, LMN) B. Accomodation- requires thickening of the lens (cilliary body muscles, parasympathetic) -pupillary contriction (sphincter pupillae muscles, parasympathetic)

Where is ACh released? (4)

At all neuromuscular junctions involving skeletal muscle fibers At many synapses in the CNS At all neuron-to-neuron synapses in the PNS At all neuromuscular and neuroglandular junctions in the parasympathetic division of the ANS

Oligodendrocytes

(OL-ih-go-DEN-dro-sites) somewhat resemble an octopus; they have a bulbous body with as many as 15 armlike processes. Each process reaches out to a nerve fiber and spirals around it like electrical tape wrapped repeatedly around a wire. This wrapping, called the myelin sheath, insulates the nerve fiber from the extracellular fluid. For reasons explained later, it speeds up signal conduction in the nerve fiber.

What are the steps in the generation of action potentials?

(Resting potential) Depolarization to threshold Activation of sodium channels and rapid depolarization Inactivation of sodium channels and activation of potassium channels Closing of potassium channels (Resting potential)

Ependymal Cells

(ep-EN-dih-mul) cells resemble a cuboidal epithelium lining the internal cavities of the brain and spinal cord. Unlike true epithelial cells, however, they have no basement membrane and they exhibit rootlike processes that penetrate into the underlying tissue. Ependymal cells produce cerebrospinal fluid (CSF), a liquid that bathes the CNS and fills its internal cavities. They have patches of cilia on their apical surfaces that help to circulate the CSF.

2 layers of cranial dura mater

(spinal dura mater has only one) 2 dural layers around the brain are fused together except where they separate to enclose the dural venous sinuses that drain venous blood from the brain and deliver it into the internal jugular veins.

Which of the following pituitary hormones regulates fluid balance? A) LH B) ADH C) FSH D) oxytocin

B) ADH

ACTH stimulates release of hormones of both the adrenal cortex and medulla. A) True B) False

B) False

Antidiuretic hormone (ADH) is an anterior pituitary hormone. A) True B) False

B) False

Cyclic adenosine monophosphate (cAMP) is an intracellular substance that is always active. A) True B) False

B) False

Hormone secretion is controlled solely by direct stimulation by the autonomic division of the central nervous system. A) True B) False

B) False

Hormones of the adrenal medulla are released in response to an anterior pituitary gland hormone. A) True B) False

B) False

The adrenal glands are anatomically closely associated with the liver. A) True B) False

B) False

The two lobes of the thyroid gland are located on either side of the trachea superior to the larynx. A) True B) False

B) False

Thyronine is the most active of the hormones produced by the thyroid gland. A) True B) False

B) False

What is Ipsilateral 3rd nerve palsy? (6 presentations)

-loss of all eye movements except for abduction, diplopia during upward gaze, downward gaze to the side opposite the lesion. -lateral strabismus -severe ptosis of upper eyelid -dilated, fixed pupil (mydriasis) -Loss of pupillary light responses -cannot converge and accommodate for near vision

Which of these would you not find in the cerebral cortex? cell bodies unmyelinated axons dendrites fiber tracts

...

Nervous system coordinating task

1) Though sense organs and simple sensory nerve endings, it receives information about changes in the body and the external environment and transmits coded messages to the central nervous system. 2) The CNS processes this information, relates to past experiences and determines what response, if any is appropriate to the circumstances. 3) The CNS issues commands primarily to muscle and gland cells to carry out such responses.

Describe the three general functions of the nervous system

1. Collect information (stimuli) from receptors and relay it via nerves to the brain. 2. Process and evaluate information 3. Initiate response to information as motor out put via nerves to effectors

4 major parts of the adult brain

1. brain stem 2. cerebellum 3. diencephalon 4. cerebrum

What are the names of the three parts of basal nuclei?

1. caudate nucleus 2. putamen 3. globus pallidus

Neurons and neuroglia #'s in the brain

100 billion neurons and 10 - 50 trillion neuroglia

There are ____ pairs of cranial nerves.

12

There are __________ pairs of cranial nerves.

12

true

12 pairs of cranial nerves transmit info to and from the brain true or false?

The adult spinal cord is about__ long

18 inches

What is the difference between a chemically gated channel and a voltage-gated channel in terms of how they function?

Both are normally closed. Chemically gated channels open in response to binding of a neurotransmitter and allow a specific type of ion (s) to diffuse across the plasma membrane. Voltage-gated channels open in response to changes in electrical charge, potential, across the plasma membrane and when open they allow specific types of ions to diffuse across the membrane.

Survival Center

Brain Stem

Oxygen and glucose use by the brain

Brain only makes up 2% of total body weight but consumes about 20% of the oxygen and glucose used, even at rest. Neurons synthesize ATP almost exclusively from glucose via reactions that use oxygen. Almost no glucose is stored in the brain, so the supply must be continuous. If blood entering the brain has a low level of glucos, mental confusion, dizziness, convulsion and loss of consciousness may occur.

language areas

Broca's speech area, Wernicke's area, and other language areas are located in the left cerebral hemisphere of most people, regardless of whether they are left-handed or right-handed. Injury to language areas of the cerebral cortex results in aphasia (a-FĀ-zē-a; a- = without; -phasia = speech), an inability to use or comprehend words

What carries sensory information and motor commands in the PNS?

Bundles of axons, or NERVE FIBERS

Outline 3 ways in which receptors can be classified

By modality: chemo-, thermo-, mechano-, photo- receptors and nociceptors By origin of stimuli interoceptors - detect internal stimuli (from organs) - produce feelings such as pressure and pain etc proprioceptors - sense body position and movements - in muscles, tendons and joints etc exteroceptors - detect external stimuli - vision, hearing, taste etc By distribution in the body general senses - widely distributed (somatic) special senses - limited to head, innervated by CNs

Which of the following regions of the brain provides the precise timing and appropriate patterns of skeletal muscle contraction for the smooth, coordinated movements and agility that are needed for our daily living? pons midbrain medulla oblongata cerebellum

By processing and interpreting impulses from the motor cortex and brain stem nuclei, as well as the sensory pathways, the cerebellum provides the precise timing and appropriate patterns of skeletal muscle contraction for the smooth, coordinated movements and agility needed for daily activities (e.g., driving, typing, and tying our shoes). It also plays a poorly understood role in cognition. Cerebellar activity occurs subconsciously (we are not aware of it).

Which of the following hormones chronically increase in response to stress? A) epinephrine and norepinephrine B) cortisol and epinephrine C) ACTH and cortisol D) cortisol and oxytocin

C) ACTH and cortisol

Choose the true statement regarding the pituitary gland. A) The hypophyseal portal veins are associated with the posterior lobe of the pituitary gland. B) The pituitary in the adult consists of anterior, intermediate and posterior lobes. C) Secretion of pituitary hormones is regulated by the hypothalamus. D) Most of the pituitary hormones are secreted by the posterior lobe

C) Secretion of pituitary hormones is regulated by the hypothalamus

A characteristic of the negative feedback system that regulates hormone secretion is A) activation by imbalance B) exertion of an inhibitory effect on the gland C) exertion of a stimulatory effect on the gland D) a tendency for hormone levels to fluctuate widely

B) exertion of an inhibitory effect on the gland

The action of insulin that most directly leads to lowered blood sugar is A) enhancing glucose absorption from the small intestine B) facilitating the transport of glucose across the cell membrane C) promoting the release of glucose from the liver D) stimulating conversion of noncarbohydrates into glucose

B) facilitating the transport of glucose across the cell membrane

Hypothyroidism in an infant directly leads to A) hyperactivity B) mental retardation C) excessive appetite D) excessive bone formation

B) mental retardation

The hormone melatonin is secreted by the A) thymus B) pineal gland C) gonads D) hypothalamus

B) pineal gland

The effect of parathyroid hormone is to A) reduce absorption of calcium and phosphorus from the large intestine B) stimulate bone to release calcium C) stimulate the kidney to excrete excess calcium and phosphorus D) suppress release of parathyroid releasing hormone from the anterior lobe of the pituitary

B) stimulate bone to release calcium

Name and describe the 3 layers of the meninges, listing them from superficial to deep.

Dura mater-superficial layer; tough connective tissue, Arachnoid mater-middle layer;web-appearence and blood vessels, Pia mater-deepest layer; delicate

the transmembrane potential (voltage)

During an action potential of a neuron, what directly causes the different channels to open and close? a. calcium ions b. neurotransmitter binding to chemically gated channels c. the transmembrane potential (voltage) d. Sodium and potassium ions

gyri

During embryonic development, when brain size increases rapidly. Thus, the gray matter of the cortex enlarges much faster than the deeper white matter As a result, the cortical region rolls and folds upon itself. These are the folds. aka convolutions

potassium ions move out of the cell

During repolarization of a neuron a. both sodium and potassium ions move into the cell. b. potassium ions move into the cell. c. potassium ions move out of the cell. d. sodium ions move out of the cell. e. sodium ions move into the cell.

What are the three connective tissue wrappings in a nerve, and what specific structure does each ensheathe?

Epineurium: thick layer of dense irregular connective tissue enclosing the entire nerve and providing support and protection. Perineurium layer is dense irregular connective tissue wrapping fascicles which are bundles of axons and supporting blood vessels. Endoneurium is delicate layers of areolar connective tissue separating and electrically insulating each axon.

Importance of brain blood flow

Even a brief slowing of brain blood flow may cause unconsciousness.

Cells with a membrane potential have what property

Excitability

Types of Axonal Transport

Fast and Slow

Which type of axonal transport is both anterograde and retrograde? Give examples of substances transported by this method.

Fast axonal transport is both anterograde moving vesicles, organelles and glycoproteins toward the synapes. Retrograde fast axonal transport moves used vesicles and potentially harmful agents from synaptic knob to the cell body, possibly even hormone like molecules used for retrograde communication between neurons. (This is contrary to what we think of as normal conduction of movement from one neuron to another)

Distinguish between fast axonal transport and slow axonal transport, and give examples of the different substance moved by each.

Fast axonal transport: approximately 400 mm/day and involves movement along microtubules powered by motor protiens that use ATP for energy suppoy. Fast axonal transport is either anterograde (from cell to synaptic knob) or retrograde (from synaptic knob to cell body). Slow axonal transport: approximately .1-3mm/day. Movement results from flow of axoplasm called axoplasmic flow and is only anterograde (from cell body to synaptic knob).

Cranial Nerve IX

Glossopharyngeal Nerve Major function: Carry nerve impulses association with swallowing, salivation and taste

extra sodium ions enter a cell

EPSPs (excitatory postsynaptic potentials) occur when a. extra sodium ions enter a cell. b. hyperpolarizations occur. c. more potassium ions than usual leak out of a cell. d. more calcium ions than usual leak out of a cell. e. chloride ions enter a cell.

True

Each portion of the spinal cord served by a spinal nerve is called a segment of the cord.

What are the different types of effectors controlled by the nervous system?

Effectors include all three types of muscle tissue and glands.

If a synapse involves direct physical contact between cells what is it called?

Electrical

Anterograde Transport

Has a motor protein called kinesin

Anaxonic Neurons

Have multiple dendrites but no axon. They communicate through their dendrites and do not produce action potentials. Some anaxonic neurons are found in the brain, retina, and adrenal medulla. In the retina, they help in visual processes such as the perception of contrast.

Multipolar Neurons

Have one axon and multiple dendrites. This is the most common type and includes most neurons of the brain and spinal cord.

Bipolar Neurons

Have one axon and one dendrite. Examples include olfactory cells of the nasal cavity, certain neurons of the retina, and sensory neurons of the inner ear.

it would last indefinitely

How would the absolute refractory period be affected if voltage-regulated sodium channels failed to inactivate? a. It would last indefinitely. b. It would be basically unaffected. c. It would be much briefer.

The hormones secreted by the anterior lobe of the pituitary gland include all of the following except A) growth hormone B) prolactin C) oxytocin D) adrenocorticotropic hormone (ACTH)

C) oxytocin

The action of a hormone is directed at A) its site of secretion B) growing and dividing cells C) target cells D) cell membranes

C) target cells

The thymus gland produces a hormone that is important in the differentiation of A) glial cells B) dermal cells C) white blood cells D) muscle cells

C) white blood cells

Peripheral Nervous System (PNS)

Consist of all of the rest; it is composed of nerves and ganglia. It is functionally divided into sensory and motor division, and each of these is further divided into somatic and visceral subdivisions.

Central Nervous System (CNS)

Consists of the brain and spinal cord, which are enclosed and proctected by the cranium and vertebral column.

What does the Edinger-Westphal nucleus control? (In reference to the Middle Portion of the midbrain) What kind of Nucleus is this?

Contains preganglionic parasympathetic neurons that control (via CILLIARY GANGLION) the CILLIARY BODY MUSCLE and sphincter pupillae muscle (2 of the 3 intraocular muscles); the remaining intraocular muscle, the dilator pupillae muscle is innervated by sympathetic nerve fibers from the superior cervical ganglion. - G.V.E. Nucleus

How does action potential move along an unmyelinated axon?

Continuous propogation

Brain stem

Continuous with the spinal cord and consists of the medulla oblongata, pons and midbrain

Cranial meninges

Continuous with the spinal meninges - have the same basic structures - bear the same names: 1. outer dura mater 2. middle arachnoid mater 3. inner pia mater

What does the Somatic Nervous System (SNS) do?

Controls voluntary skeletal muscle contractions

Protective coverings of the brain

Cranium and the cranial meninges - surround and protect the brain

The reflex that complements a withdrawal reflex, making compensatory adjustments on the side of the body opposite that which receives the stimulus is the __

Crossed extensor reflex

What reflex had a contralateral component

Crossed-extensor

What are the functions of the cerebrospinal fluid?

Cushion, support, and transport substances such as nutrients, chemical messengers, and wastes from neural tissues.

Perikaryon

Cytoplasm surrounding the nucleus

Regions of the spinal cord are expanded to accommodate sensory and motor information associated with the limbs. These expanded areas are called the__

Cervical and lumbar enlargements

True

Cervical and lumbar enlargements are wide points in the cord marking the emergence of motor nerves.

What is a chemical gradient?

Chemical gradients are created when there are unequal concentrations of substances inside or outside of the cell. These gradients create a currents that try to normalize the concentrations.

Describe the essential structural and functional difference between a chemical and electrical synapse.

Chemical synapses are most common and composed of a pre synaptic neuron (signal producer) and post synaptic neuron (signal receiver or target). To transmit between pre and post synaptic neurons neurotransmitter molecules stored in synaptic vesicles are released from the knob of one neon into the synaptic cleft. Some of theme diffuse across and bind. There is a synaptic delay between the release, diffusion and binding which is usually be tween .3 and .5 milliseconds. Electrical synapses are much less common and composed of a pre and post synaptic neuron physically bound, gap junctions facilitate the flow of ions between the cells and they act like they share a common plasma membrane. Electrical synapses are located within limited regions of the brain and eyes.

What are the three classes of gated channels and briefly describe how each one opens and closes?

Chemically gated channels - Open or close when they bind specific chemicals Voltage gated channels - Open or close in response to changes in the transmembrane potential Mechanically gated channels - Open or close in response to physical distortion of the membrane surface

acetylcholine

Cholinergic synapses release the neurotransmitter a. norepinephrine. b. GABA. c. acetylcholine. d. serotonin. e. adrenalin.

slow closing of voltage-gated k+ channels

Hyperpolarization results from __________. a. fast closing of voltage-gated K+ channels b. slow closing of voltage-gated K+ channels c. slow closing of voltage-gated Na+ channels

Cranial Nerve XII

Hypoglossal nerve Major function: Control tongue muscles

Visceral Command Center

Hypothalamus

sensory

I feel pain in my little finger

sensory

I'm cold

sensory

I'm hearing voices

Where are interneurons located, and what is their function?

Most interneurons are located inside the CNS and make up 99% of human neurons. They are the facilitators of communication and they receive, process and store information before deciding on how to respond to that information.

False

Most nerves are motor nerves.

a multipolar neuron that has two or more dendrites and a single axon

Motor neurons are an example of what type or class of neuron? a. a bipolar neuron that has two processes separated by the cell body b. a unipolar neuron that has a single elongated process, with the cell body located off to the side c. a multipolar neuron that has two or more dendrites and a single axon d. an anaxonic neuron that has processes that are all dendrites

False

Motor signals typically begin in an upper motor neuron in the thalamus.

Group of muscle fibers innervated by a single neuron

Motor unit

What is the most common type of neuron in the CNS?

Multipolar neuron

Muscle cell aka

Muscle fiber

saltatory

Myelin limits the movement of ions across the axon membrane, so the action potential "jumps" from node to node along the axon. This is an example of what type of propagation? a. graded b. hyperpolarization c. continuous d. saltatory

The white matter of the spinal cord contains ____

Myelinated and Unmyelinated Nerve Fibers

Define myelination, and describe the composition and function of a myelin sheath.

Myelination is the process by which part of an axon is wrapped with myelin an insulating covering that consists of repeating concentric layers of plasma membrane of glial cells. Neurolemmocytes in the PNS and oligodendrocytes in the CNS complete myelination. The high lipid content gives the axon a glossing, white appearance and insulates the axon.

Neurofibrils

Neurofilaments that provide internal support ofr dendrites and axons

have lower membrane resistance to ion movement

In contrast to the internodes of a myelinated axon, the nodes __________. a. only occur at the beginning and end of the axon b. have higher membrane resistance to ion movement c. have lower membrane resistance to ion movement d. are wrapped in myelin

contract and the antagonist muscles, the hamstrings, to relax.

In the patellar tendon reflex arc, the patellar ligament is stretched, which stretches the quadriceps femoris muscle of the thigh. This reflex will cause the quadriceps femoris to

initial segment of the axon

In what part of the neuron does the action potential typically initiate? a. initial segment of the axon b. dendrites c. axon terminals d. soma (cell body)

Myelin sheath function

Increase speed of action potential conduction

What is the role of ions, the phospholipid bilayer, and plasma membrane channels in neurons relative to the concepts of current, voltage and resistance?

Ion: charged particles. Phospholipid Bi-layer: restricts ion movements b/c it usually doesn't allow charged particles to diffuse directly across, they must be involved in some type of transport. Plasma membrane channels: channels that open and close within the plasma membrane to allow ions in or out of the cell. Resistance is less when ion channels are open and resistance is greater when ion channels are closed and current is generated when ions move back and forth through the channels.

Damage to the CN 3 results in what?

Ipsillateral 3rd nerve palsy

The Hypothalamus

Is The Thermostat Of The Body Because It Regulates Temperature

Nerve

Is a bundle of nerve fibers (axons) wrapped in fibrous connective tissue. Nerves emerge from the NCS through foramina of the skull and vertebral column and carry signals to and from other organs of the body.

Ganglion

Is a knotlike swelling in a nerve where the cell bodies of neurons are concentrated

Why is the spinal cord described as being segmented?

It appears segmented because the nerves come out of intervels

What kind of Nerve is Cranial nerve 3:

It is a motor nerve

Why is regeneration in the CNS limited? What makes it more complicated? (3)

Many more axons are likely to be involved Astrocytes produce scar tissue that can prevent axon growth across the damaged area Astrocytes release chemicals that block the regrowth of axons

Which of the following is NOT a feature of the major spinal cord tracts (pathways)? decussation relay memory somatotopy

Memory is a function of the brain (not the spinal cord).

Which of the following is a characteristic of a coma but is NOT a characteristic of sleep? absence of brain waves ("flat EEG") irreversible brain damage continuously reduced mitochondrial activity in brain neurons All of the listed responses are correct.

Mitochondria are cytoplasmic organelles that produce ATP that provide energy for other cellular activities. Oxygen consumption during sleep resembles that of the waking state. In coma patients, in contrast, oxygen use is always below resting levels.

List the 5 primary taste sensation and state their location on the tongue

Molecules must dissolve in saliva and flood the taste pore. 5 primary sensations - throughout tongue Sweet - concentrated on tip Salty - lateral margins Sour - lateral margins Bitter - posterior (back of tongue) (lowest threshold) Umami (meaty or savoury) - taste of amino acids (MSG)

Distinguish between a monosynaptic reflex arc and a polysynaptic reflex arc.

Monosynaptic reflex arc-one synapse; two neurons, Polysynaptic reflex arc-more than one synapse; 3 or more neurons

Supportive Cells

Neuroglia or glial cells. Glial cells protect the neurons and help them function. The word glia, which means "glue," implies one of their roles—to bind neurons together and provide a supportive framework for the nervous tissue. In the fetus, glial cells form a scaffold that guides young migrating neurons to their destinations. Wherever a mature neuron is not in synaptic contact with another cell, it is covered with glial cells. This prevents neurons from contacting each other except at points specialized for signal transmission, and thus gives precision to their conduction pathways.

Distinguish between the myelination process carried out by neurolemmocytes and by oligodendrocytes.

Neurolemmocytes in the PNS can only myelinate small portions os a single axon and often it takes many neurolemmocytes to myelinate entire axons. Oligodendrocytes in the CNS can myelinate many axons at the same time and not just one.

Which specific type of glial cells ensheath axons in the PNS?

Neurolemmocytes or Schwann cells are flattened cells that form myelin sheaths and allow faster AP propagation.

How does myelination of axons occur in the PNS?

Neurolemmocytes start to wrap around a portion of the axon. Neurolemmocyte cytoplasm and plasma membrane begin to form consecutive layers around the axon as wrapping continues the overlapping inner layers of the neurolemmocyte plasma membrane form the myelin sheath Eventually, the neurolemmocyte cytoplasm and nucleus are pushed to the periphery of the cell as n the myelin sheath is formed.

Neural tissues includes what two types of tissue?

Neurons and neuroglia

How are the different processes that extend from a cell body used to structurally classify nerons?

Neurons are classified by the number of processes that come directly from the cell body (soma).

Classification of Neurons

Neurons are classified structurally according to the number of processes extending from the soma. Multipolar neurons, bipolar neurons, unipolar neurons, anaxonic neurons.

Describe five distinguishing features common to all neurons.

Neurons are the basic structural unit of the nervous system and are distinguished by: 1. Excitability - responsiveness to stimulation 2. Conductivity - propagation of electrical charges 3. Secretion - neurotransmitters are released in response to conductive activity. 4. Extreme longevity - formed during fetal development and functional in elderly. 5. Amitotic - during fetal development most mitotic activity stops except olfactory epithelium and some areas of the brain.

What does the Occulomotor nucleus control? (In reference to the Middle portion of the midbrain) What type of function is this?

Occulomotor Nucleus- contains the cell bodies of LMN that innervate 4 out of 6 extraocular muscle (superior ,medial and inferior rectus, inferior oblique muscle) and skeletal muscle portion of the levator palpebrae superioris muscle. Involved in all eye movement except abduction. Elevates upper eyelids - A GSE function

Cranial Nerve III

Oculomotor nerve Major function: Control some of the muscles moving the eyeballs, changes in size of pupil and shape of lens

Pneumonic for Cranial Nerve numbers

Oh, Oh, Oh, To Touch and Feel Very Green Vegetables, AH!

Cranial Nerve I

Olfactory nerve Major function: Smell

somatic NS automatic NS

PNS is divided into

cranial and spinal nerves

PNS is made of

Nuclei of cranial nerves V, VI, VII are found in the___

Pons

What is the Locus Ceruleus ?

Portion of the brain that is blue due to the tyrosine action in melanocytes when producing N.E.

Breakdown of the BBB

Possible by trauma, toxins and inflammation

Only tract in the Periaqueductal grey

Posterior longitudinal fasciculus

True

Posterior root ganglia contain somas of unipolar neurons

Location of Cerebellum

Posterior to brain stem

Define a postsynaptic potential

Postsynaptic potentials are graded potentials that occur in postsynaptic neurons specifically, usually because the neuron can bind many neurotransmitter molecules simultaneously. The type of GP (depolarized or hyper polarized) depends on if the neurotransmitters that were released are inhibitory or excitation.

What are the two parts/cells that are involved in a synapse and briefly describe both

Presynaptic cell - Sends the message and includes the synaptic terminal Postsynatpic cell - Receives the message

calcium channels in the presynaptic membrane remaining open longer

Presynaptic facilitation by serotonin is caused by a. calcium channels in the presynaptic membrane remaining open longer. b. blockage of calcium channels in the presynaptic membrane. c. temporal summation. d. increased extracellular concentration of sodium ion. e. increased extracellular concentration of potassium ion.

What does the Autonomic Nervous System (ANS) do?

Provides automatic regulation of smooth muscle, cardiac muscle, glandular secretions, and adipose tissue at the subconscious level

the axon would be unable to generate action potentials

Puffer fish poison blocks voltage-gated sodium channels like a cork. What effect would this neurotoxin have on the function of neurons? a. The absolute refractory period would be shorter than normal. b. Neurons would depolarize more rapidly. c. Action potentials would lack a repolarization phase. d. The axon would be unable to generate action potentials. e. None, because the chemically gated sodium channels would still function.

Sensory (afferent) neurons

Specialized to detect stimuli such as light, heat, pressure, and chemicals, and transmit information about them to the CNS. Such neurons begin in almost every organ of the body and end in the CNS; the word afferent refers to signal conduction toward the CNS. Some receptors, such as those for pain and smell, are themselves neurons. In other cases, such as taste and hearing, the receptor is a separate cell that communicates directly with a sensory neuron.

Functional Organization of the Cerebral Cortex

Specific types of sensory, motor, and integrative signals are processed in certain regions of the cerebral cortex

If the posterior portion of the neural tube failed to develop properly the ___

Spinal Cord May Be Affected

Segmental refers to what level of motor control

Spinal cord

What does the CNS consist of?

Spinal cord and brain

False

Spinal cord conducts signals up and down the body passing through gray and white matter, respectively.

Explain how nerves are classified structurally and functionally.

Structural classification depends on which CNS component the nerve comes from; cranial nerves extend from the brain and spinal nerves extend from the spinal cord. Functional classification is sensory containing only sensory neurons that relay information to the CNS and motor which relay information from the CNS. Some mixed nerves contain both but usually only transmit one type of information.

Name and describe the four structural categories of neurons.

Structural classification of neurons include multipolar, bipolar, unipolar or anaxonic neurons. Multipolar: multiple nerve processes extending directly from the cell body; typically many dendrites and one axon. Bipolar: two nerve cell processes extend directly from the cell body; one dendrite and oen axon. Unipolar: single short celll process extends directly from the cell and looks like a T as a result of the fusion of two processes into one long axon. Anaxonic: nerve cell processes are only dendrites; no axon present.

Identify the structural components included in both the CNS and the PNS

Structural components of the CNS include the brain and spinal cord. Structural components of the PNS include nerves, which are bundles of axons and ganglia that are clusters of neuron cell bodies along the nerves.

Define summation, and describe the two types of summation that can occur in the initial segment.

Summation is the accumulation of stimuli occurring in neurons or muscle cells; e.g., wave summation. Spatial summation involves multiple presynaptic neurons releasing multiple neurotransmitters ant multiple locations onto the receptive segment - if enough EPSPs then an AP is generated. Temporal summation occurs when a single presynaptic neuron releases excitatory neurotransmitters to stimulate the postsynaptic neuron at a single location many times very rapidly. If they reach the axon hillock in time they are added together and an AP may be reached.

Location of diencephalon

Superior to brain stem. - consists of thalamus, hypothalamus and epithalamus

Cerebrum

Supported on the diencephalon and brain stem - largest part of the brain

Neuroglia

Supporting cells whose functions are essential to the survival & functionality of neurons and the preservation of the physical & biochemical structure of neural tissue

the limbo- sacral plexus that supplies the pelvic girdle and the leg includes the spinal nerves

T12-S4

Describe the projection pathways for taste

Taste buds are innervated by the: facial nerve (VII) - anterior 2/3's of tongue glossopharyngeal nerve (IX) - posterior 1/3 vagus nerve (X) - palate, pharynx, epiglottis •Taste fibres project to medulla (solitary nucleus) •Second order neurons project signals to either the hypothalamus and amygdala (reflex responses such as salivating or gagging) or the thalamus then cerebrum (consciousness of taste)

What are the organs of the nervous system

The brain, spinal cord, nerves, and sensory receptors

cauda equina.

The bundle of nerve roots that occupy the vertebral canal from L2 to S5 is called the

vermis

The central constricted area of the cerebellum

phrenic

The cervical plexus gives origin to the ___ nerve(s

corpus callosum

a broad band of white matter that containing axons that connects the cerebral hemispheres. Extends between them. (sits deep inside the brain)

What is a stimulus?

a change in the internal or external environment

CNS nucleus

a collection of neuron cel bodies with a common function and a discrete anatomical boundary

If the ventral root of a spinal nerve were cut, what would be the result in the tissue or region that nerve supplies?

a complete loss of voluntary movement

f the ventral root of a spinal nerve were cut, what would be the result in the tissue or region that nerve supplies? Choose one answer. a. complete loss of sensation b. a complete loss of voluntary movement c. loss of neither sensation nor movement but only of autonomic control d. a complete loss of sensation and movement

a complete loss of voluntary movement

What part of the spinal cord represents the collection of nerve roots at the inferior end of the vertebral canal? cervical enlargement lumbar enlargement conus medullaris cauda equina

The collection of nerve roots at the inferior end of the vertebral canal is named the cauda (tail) equina (horse) because it resembles a horse's tail. This strange arrangement reflects the fact that during fetal development, the vertebral column grows faster than the spinal cord, forcing the lower spinal nerve roots to "chase" their exit points inferiorly through the vertebral canal.

All-or-none principal

The concept that a given stimulus either triggers a typical action potential, or none at all

Structure of a Neuron

The control center of the neuron is the soma,7 also called the neurosoma, cell body, or perikaryon8 (PERR-ih-CARE-ee-on). It has a single, centrally located nucleus with a large nucleolus. The cytoplasm contains mitochondria, lysosomes, a Golgi complex, numerous inclusions, and an extensive rough endoplasmic reticulum and cytoskeleton. The cytoskeleton consists of a dense mesh of microtubules and neurofibrils (bundles of actin filaments), which compartmentalize the rough ER into dark-staining regions called Nissl9 bodies (fig. 12.4e). Nissl bodies are unique to neurons and a helpful clue to identifying them in tissue sections with mixed cell types. Mature neurons have no centrioles and apparently undergo no further mitosis after adolescence; however, they are unusually long-lived cells, capable of functioning for over a hundred years. Even into old age, however, there are unspecialized stem cells in the CNS that can divide and develop into new neurons. The control center of the neuron is the soma,7 also called the neurosoma, cell body, or perikaryon8 (PERR-ih-CARE-ee-on). It has a single, centrally located nucleus with a large nucleolus. The cytoplasm contains mitochondria, lysosomes, a Golgi complex, numerous inclusions, and an extensive rough endoplasmic reticulum and cytoskeleton. The cytoskeleton consists of a dense mesh of microtubules and neurofibrils (bundles of actin filaments), which compartmentalize the rough ER into dark-staining regions called Nissl9 bodies (fig. 12.4e). Nissl bodies are unique to neurons and a helpful clue to identifying them in tissue sections with mixed cell types. Mature neurons have no centrioles and apparently undergo no further mitosis after adolescence; however, they are unusually long-lived cells, capable of functioning for over a hundred years. Even into old age, however, there are unspecialized stem cells in the CNS that can divide and develop into new neurons.

True

The cross extension reflex is the contraction of the extensors on one side of the body when the flexors are contracted on the other side

fissures

The deepest grooves between folds of gyri

voltage-gated na+ channels

The depolarization phase of an action potential results from the opening of which channels? a. voltage-gated Na+ channels b. chemically gated Na+ channels c. chemically gated K+ channels d. voltage-gated K+ channels

What is an electrical gradient?

The difference in electrical charge between two areas. The total number of positive and negative charges create a gradient which moves charged ions from one place to another.

all of the answers

The effect that a neurotransmitter has on the postsynaptic membrane depends on the a. frequency of neurotransmitter release. b. quantity of neurotransmitters released. c. characteristics of the receptors. d. nature of the neurotransmitter. e. All of the answers are correct.

transverse fissure

a deep groove, which along with the tentorium cerebelli, separates the cerebellum from the cerebrum

oculomotor

a dilated and fixed pupil is caused by pressure on this nerve

What is a reflex?

a fast, unplanned sequence of events in response to a stimulus

Which functional segment of a neuron contains voltage-gated channels?

The initial segment composed of the axon hillock contains voltage-gated Na+ and K + channels. The conductive segment or length of the axon and branches contains both voltage-gated Na+ and K+ channels. The transmissive segment includes synaptic knobs and voltage-gated Ca2+ channels.

Subarachnoid Space

a fluid filled space surrounding the brain

flexor reflex

a form of withdrawal reflex in which the muscles of a limb contract to move the limb away from a source of stimulation

fascicle

a group of nerve fibers

precentral gyrus

a major gyrus - located immediately anterior to the central sulcus - contains the primary motor area of the cerebral cortex

postcentral gyrus

a major gyrus - located immediately posterior to the central sulcus - contains the primary somatosensory area of the cerebral cortex.

stretch reflex

a monosynaptic reflex that prevents excessive stretching of skeletal muscles

the final step involved in a neural reflex i

a response by an effector

hypothalamus

a small part of the diencephalon located inferior to the thalamus. It is composed of a dozen or so nuclei in four major regions - Controls and integrates activities of the autonomic nervous system and pituitary gland. - Regulates emotional and behavioral patterns and circadian rhythms. - Controls body temperature and regulates eating and drinking behavior. - Helps maintain the waking state and establishes patterns of sleep. - Produces the hormones oxytocin and antidiuretic hormone (ADH).

Achilles tendon reflex

a stretch reflex; tapping this tendon in the heel normally causes plantar flexion of the foot; also called the ankle-jerk reflex

calcium

The ion that triggers the release of acetylcholine into the synaptic cleft is a. chloride. b. calcium. c. potassium. d. sodium. e. magnesium.

Myelin

The myelin (MY-eh-lin) sheath is an insulating layer around a nerve fiber, somewhat like the rubber insulation on a wire. It is formed by oligodendrocytes in the central nervous system and Schwann cells in the peripheral nervous system. Since it consists of the plasma membranes of these glial cells, its composition is like that of plasma membranes in general. It is about 20% protein and 80% lipid, the latter including phospholipids, glycolipids, and cholesterol.

presynaptic inhibition

The neurotransmitter GABA blocks presynaptic voltage-gated calcium channels. Consequently, GABA produces __________. a. EPSPs b. presynaptic facilitation c. presynaptic inhibition d. IPSPs

saltatory propagation

The node-to-node "jumping" regeneration of an action potential along a myelinated axon is called __________. a. saltatory propagation b. local propagation c. myelinated propagation d. continuous propagation

cerebral cortex

The outer rim of gray matter of the cerebrum - 2-4 mm thick - contains billions of neurons. - Deep to the cerebral cortex lies the cerebral white matter.

Refractory period

The period between the initiation of an action potential and the restoration of the normal resting potential

The brain

The portion of the central nervous system contained within the cranium.

Repolarization

The process of restoring the normal resting potential after depolarization

monosynaptic

The quickest reflex arcs involve only two neurons, thus forming __ reflex arcs.

Which functional segment of a neuron contains chemically gated channels?

The receptive segment includes both dendrites and the cell body and contain chemically gated channels.

the opening of voltage-gated k+ channels

The repolarization phase of an action potential results from __________. a. the opening of voltage-gated Na+ channels b. the opening of voltage-gated K+ channels c. the closing of voltage-gated K+ channels d. the closing of voltage-gated Na+ channels

premotor area

a motor association area that is immediately anterior to the primary motor area. - Neurons in this area communicate with the primary motor cortex, the sensory association areas in the parietal lobe, the basal ganglia, and the thalamus. The premotor area deals with learned motor activities of a complex and sequential nature. It generates nerve impulses that cause specific groups of muscles to contract in a specific sequence, as when you write your name. The premotor area also serves as a memory bank for such movements.

third ventricle

a narrow cavity along the midline superior to the hypothalamus and between the right and left halves of the thalamus

How are EPSP and IPSP graded potentials established in the receptive segment of a neuron?

The type and strength of the graded potential generated in the receptive segment of a neuron depend on the number and type of neurotransmitters that bind to the dendrites. EPSP's will be more likely to generate an action potential than IPSP neurotransmitters will be.

the precentral gyrus of the cerebrum.

The upper motor neurons that control skeletal muscles begin with a soma in

a small myelinated axon

The velocity of the action potential is fastest in which of the following axons? a. a small myelinated axon b. a large unmyelinated axon c. a small unmyelinated axon

the thoracic region

The ventral rami of the spinal nerves form nerve plexuses in all regions except

anterior horn

This figure shows a cross section of the spinal cord. What does "3" represent?

How is the Substantia Niagra tied to Parkinson's disease?

This disease is characterized by the loss of dopaminergic neurons in the substantia niagra.

C6

This figure shows a dermatome map. A patient with no sensation in the left thumb would probably have a nerve damaged in

posterior root of a spinal nerve

This figure shows a detail of the spinal cord, meninges and spinal nerves. What does "1" represent?

arachnoid mater

This figure shows a detail of the spinal cord, meninges and spinal nerves. What does "4" represent?

perineurium

This figure shows the anatomy of a nerve. What does "3" represent?

the cervical enlargement

This figure shows the posterior aspect of spinal nerve roots and plexuses. What does "2" represent?

brachial plexus

This figure shows the posterior aspect of spinal nerve roots and plexuses. What does "3" represent?

tendon reflex

This reflex shows the least synaptic delay.

What is the significance of the threshold membrane potential in the initial segment of a neuron?

Threshold membrane potential is the on/off switch for an AP to be propagated along the axon of the neuron. If it is reached in the initial segment than it will generate an AP. The AP will have equal intensity regardless of the intensity of the response as long as it is enough to reach the threshold.

What is most likely to experience ototoxicity?

a person who took an antibiotic drug that injured CN VIII

A postsynaptic potential is a graded potential that is the result of a neurotransmitter released into the synapse between two neurons.

True

Association fibers communicate between gyri in the same cerebral hemisphere.

True

CNS nerve fibers lack the intrinsic capacity to regenerate, while PNS nerve fibers are able to regenerate.

True

Cell bodies of sensory neurons may be located in ganglia lying outside the central nervous system.

True

Cell bodies of the somatic motor neurons of the spinal nerves are located in the ventral horn of the spinal cord. Answer: True False

True

Dermatomes are skin segments that relate to sensory innervation regions of the spinal nerves.

True

Dermatomes are skin segments that relate to sensory innervation regions of the spinal nerves. Answer: True False

True

Dorsal and ventral rami are similar in that they both contain sensory and motor fibers.

True

Efferent nerve fibers may be described as motor nerve fibers.

True

Embryonic damage to the mesencephalon could result in improper formation of the midbrain.

True

Embryonic damage to the mesencephalon could result in improper formation of the midbrain. Answer: True False

True

In most people, the left cerebral hemisphere has greater control over language abilities, math, and logic.

True

In myelinated axons the voltage-regulated sodium channels are concentrated at the nodes of Ranvier.

True

In the somatosensory system there are no third-order neurons in the cerebellum.

True

In the somatosensory system there are no third-order neurons in the cerebellum. Answer: True False

True

Irritation of the phrenic nerve may cause diaphragm spasms called hiccups.

True

Irritation of the phrenic nerve may cause diaphragm spasms called hiccups. Answer: True False

True

Large-diameter nerve fibers conduct impulses much faster than small-diameter fibers.

True

Most of the ascending and descending pathways to and from the brain cross over from one side of the body to the other. Answer: True False

True

In which of the following would the delay between stimulus and response be greater? a polysynaptic reflex a monosynaptic reflex

a polysynaptic reflex

crossed extensor reflex

a polysynaptic reflex in which the motor response occurs on the side posit the stimulus

Neurons and nerve cells are different names for the same thing.

True

One functional center found within the medulla oblongata is a respiratory center involved in the control of the rate and depth of breathing. Answer: True False

True

Pacinian corpuscles can be exteroceptors, interoceptors, or proprioceptor,

True

Petit mal seizures found in children generally go away with age. Answer: True False

True

Specific motor and sensory functions are localized in specific areas called domains, whereas memory and language have overlapping domains. Answer: True False

True

T/F spinal nerves have mixed motor and sensory function

True

T/F the term cerebral dominance designates the hemisphere that is dominant for language

True

The adult spinal cord ends between L1 and L2. Answer: True False

True

The cerebellum and basal nuclei are involved in regulating motor activity, starting and stopping movements, and coordinating postural movements.

True

The first obvious sign that the nervous system is forming in the embryo is the thickening of the surface ectoderm to form the neural plate. Answer: True False

True

The meningeal branch of a spinal nerve actually reenters the vertebral canal to innervate the meninges and blood vessels.

True

The meningeal branch of a spinal nerve actually reenters the vertebral canal to innervate the meninges and blood vessels. Answer: True False

True

The musculocutaneous nerve is a major nerve of the brachial plexus.

True

The only cranial nerves to extend beyond the head and neck region are the vagus nerves. Answer: True False

True

The primary visual cortex contains a map of visual space. Answer: True False

True

The second cranial nerve forms a chiasma at the base of the brain for partial crossover of neural fibers.

True

The second cranial nerve forms a chiasma at the base of the brain for partial crossover of neural fibers. Answer: True False

True

True or False: The term cerebral dominance designates the hemisphere that is dominant for language.

True

In general, a primary sensory cortex breaks down sensory input into component parts, while an association cortex makes sense of sensory inputs.

True. The primary sensory cortex receives sensory inputs in their cruder forms, while the association cortex helps you understand what the sensory input means.

External strabismus and ptosis could be caused by damage to the oculomotor nerve. Answer: True False

Ture

What two structures protect the spinal cord?

Vertebrae and meninges

Cranial Nerve VIII

Vestibulocochlear Nerve Major function: Carry nerve impulses associated with hearing and equilibrium

Why might an individual experience the phenomenon known as "referred pain"?

Visceral pain afferents travel along the same pathways as somatic pain fibers.

Integrate the concepts of voltage, current, and resistance with neuron structure and function.

Voltage (V): amount of difference in electrical charge in volts. Current (C): movement of charged particles across a barrier. Resistance (R) : opposition to the movement of charged particles. The amount of particles allowed through the barrier determine how high or low the current is. Ohm's Law: C=V/R

What is the name of the process for peripheral nerve regeneration?

Wallerian degeneration

potassium efflux

What causes repolarization of the membrane potential during the action potential of a neuron? a. potassium efflux (leaving the cell) b. sodium influx (entering the cell) c. potassium influx (entering the cell) d. sodium efflux (leaving the cell)

potassium

What ion causes repolarization of the neuron during an action potential? a. K+ (potassium) b. Ca2+ (calcium) c. Na+ (sodium) d. Mg2+ (magnesium)

a

What ion is responsible for the depolarization of the neuron during an action potential? a. Na+ (sodium) b. K+ (potassium) c. Cl- (chloride) d. Ca2+ (calcium)

d

What is NOT part of the cerebrum? a. parietal lobe b. insula c. frontal lobe d. brainstem

What is the accomodation and convergence pathway referring to ?

What is required in order to clearly visualize near objects using near vision

100mV

What is the magnitude (amplitude) of an action potential?

c

What is the neurotransmitter that a motor neuron uses to communicate with a skeletal muscle? a. dopamine b. norepinephrine c. acetylcholine d. gamma aminobutyric acid (GABA)

AChE degrades acetylcholine in the synaptic cleft

What is the primary role of the enzyme acetylcholinesterase (AChE) at a cholinergic synapse? a. AChE degrades acetylcholine in the synaptic cleft. b. AChE binds to ACh receptors, causing them to open. c. AChE releases acetylcholine into the synaptic cleft. d. AChE depolarizes the postsynaptic cell.

neurotransmitter binds to receptors on the postsynaptic cell membrane

What is the role of neurotransmitter at a chemical synapse? a. Neurotransmitter causes calcium to enter the presynaptic cell. b. Neurotransmitter binds to receptors on the postsynaptic cell membrane. c. Neurotransmitter causes vesicles to fuse with the presynaptic membrane. d. Neurotransmitter causes an action potential in the presynaptic cell.

2 ms

What is the typical duration of a nerve action potential? a. 2 ms b. 200 ms c. 0.2 ms d. 20 ms

exocytosis

What mechanism releases neurotransmitter from presynaptic neurons? a. pinocytosis b. phagocytosis c. endocytosis d. exocytosis

synaptic cleft

What separates the presynaptic and postsynaptic cells at a chemical synapse? a. synaptic cleft b. chemically gated ion channels c. calcium channels d. vesicles filled with neurotransmitter

diffusion of calcium ions into the synaptic terminal

What triggers the release of acetylcholine from a synaptic terminal? a. release of calcium ions from the synaptic vesicles b. diffusion of sodium ions out of the synaptic terminal c. diffusion of calcium ions into the synaptic terminal d. synaptic vesicles fuse to dendrites e. graded potentials in the synaptic terminal

a chemically gated channel

What type of channel in the postsynaptic membrane binds neurotransmitter? a. a chemically gated channel b. a leakage channel c. a voltage-gated channel d. a mechanically gated channel

facilitated diffusion

What type of membrane transport causes the depolarization phase of the action potential in neurons? a. facilitated diffusion b. simple diffusion c. active transport d. filtration

Collaterals

When an axon branches off along its length which enables the neuron to communicate with several other cells

sodium ions enter the postsynaptic neuron

When cholinergic receptors are stimulated, a. sodium ions leave the postsynaptic neuron. b. chloride ions enter the postsynaptic neuron. c. sodium ions enter the postsynaptic neuron. d. norepinephrine deactivates acetylcholine. e. chloride ions leave the postsynaptic neuron.

Explain depolarization and hyperpolarization.

When neurons are stimulated chemically or voltage gated channels open causing ions to flow across the membrane. When more positive ions are moved into the cell and it becomes less negative the neuron goes from RMP to a state of depolarization. Hyperpolarization is the opposite effect when the inside of the cell gains more negative charges or loses more positive charges and ultimately becomes more negative again.

How does depolarization and hyperpolarization occur in a neuron?

When neurons are stimulated, chemically or voltage gated channels open, causing a change in ion flow across the membrane that alters the resting membrane potential The type and direction of ion movement determint the tipe of polarization change.

Spatial summation

When simultaneous stimuli applied at different locations have a cumulative effect on the transmembrane potential

When does the relative refractory period begin and end?

When sodium channels regain their normal resting condition and continues until the transmembrane potential stabilizes at resting levels

Describe the initiation and propagation of depolarization and repolarization, which constitutes a nerve signal.

When the threshold is reached in the initial segment the depolarization is caused by the inside of the neuron becoming more positive because of the extra Na+ coming in, the depolarization area moves in one direction along the axon. After an area reaches threshold and moves the signal it causes the area to re polarize (become more negative again).

at the nodes

Where are action potentials regenerated as they propagate along a myelinated axon? a. at myelin b. at every segment of the axon c. at the internodes d. at the nodes

at every segment of the axon

Where are action potentials regenerated as they propagate along an unmyelinated axon? a. at myelin b. at the internodes c. at the nodes d. at every segment of the axon

initial segment

Where on the neuron is the action potential initiated? a. Cell body b. Initial segment c. Axon d. Dendrite

Axon hillock

Where the axon and the body of the neuron meet/join

the resting membrane potential is restored, but concentrations of sodium and potassium are not restored to their original state

Which answer best describes the relative refractory period in the neuron? a. The neuron cannot generate another action potential under extreme stimulation. b. Potassium ions are entering the neuron through open membrane channels. c. The neuron's membrane potential is -70 mV. d. The resting membrane potential is restored, but concentrations of sodium and potassium are not restored to their original state.

schwann cells

Which neuroglia cells form the myelin sheath of motor nerves? a. astrocytes b. ependymal cells c. satellite cells d. Schwann cells

posterior (dorsal) root

Which of the following branches of a spinal nerve have somas of solely sensory neurons?

voltage-gated sodium channels

Which of the following channels is most directly responsible for the properties of the axon that lead to action potential generation? a. Ligand-gated sodium channels b. Voltage-gated potassium channels c. Voltage-gated sodium channels d. Leak potassium channels e. Leak sodium channels f Ligand-gated potassium channels

a fracture of vertebra L4

Which of the following fractures would be the least likely to cause a spinal cord injury

muscles of the hand

Which of the following groups of muscles have the most muscle spindles?

all

Which of the following is a recognized class of opioid neuromodulators? a. endomorphins b. dynorphins c. endorphins d. enkephalins e. All of the answers are correct.

a neuron

Which of the following is an example of a presynaptic cell? a. a secretory cell b. a neuron c. a Schwann cell d. a muscle cell

it is more positive than the resting potential

Which of the following is true about threshold for an action potential? a. Voltage-gated potassium channels begin to open. b. Threshold for a typical neuron is approximately -30 mV. c. It is more positive than the resting potential. d. The membrane begins to hyperpolarize. e. Voltage-gated potassium channels begin to close.

sciatic

Which of the following nerves originates in the coccygeal plexus?

touch

Which of the following sensory functions involves neurons in the posterior root ganglia?

white matter

Which of the following structures is the richest in lipid content?

the gracile fasciculus

Which of these is an ascending tract of the spinal cord?

endorphins

Which of these substances is considered a neuromodulator? a. acetylcholine b. nitric oxide c. norepinephrine d. endorphins

somatic receptor afferent nerve fiber interneuron efferent nerve fiber skeletal muscle

Which one of the following best describes the order of a somatic reflex?

stretch (myotatic) reflex.

You go to the movies after a long day and you begin to nod off as soon as the movie starts. Your head starts to lower a little but this reflex causes your head to rise. This is called the

withdrawal reflex

a protective reflex; quickly moves your finger away form a hot object

b

a reflex with a single synapse between the sensory and motor neurons within the spinal cord is known as _______. a. visceral reflex b. monosynaptic reflex c. somatic reflex d. polysynaptic reflex

______ are collections of neuron cell bodies associated with nerves in the PNS. a) Fascicles b) Nerves c) Ganglia d) Myelin sheaths

c) Ganglia

Select the statement that is most correct. a) Ganglia are collections of neuron cell bodies in the spinal cord that are associated with efferent fibers. b) The dorsal root ganglion is a motor-only structure. c) Ganglia associated with afferent nerve fibers contain cell bodies of sensory neurons. d) The cell bodies of afferent ganglia are located in the spinal cord.

c) Ganglia associated with afferent nerve fibers contain cell bodies of sensory neurons.

Which of the following is NOT correct concerning nerves? a) Nerves do not contain cell bodies. b) Nerves are covered by an outer sheath called the epineurium. c) Nerves are collection of axons of either sensory or motor neurons but not both. d) Nerves are analogous to tracts in the CNS.

c) Nerves are collection of axons of either sensory or motor neurons but not both.

Which of the following statements is correct concerning the spinal cord? a) The white matter contains cell bodies for spinal nuclei. b) Damage to sensory tracts in the spinal cord leads to paralysis. c) Spinal nerves have mixed motor and sensory function. d) Just like the cerebrum, the gray matter is found on the superficial surfaces.

c) Spinal nerves have mixed motor and sensory function.

What type of stimulus is required for an action potential to be generated? a) multiple stimuli b) a single stimulus generated by the neuron that is to produce the action potential c) a threshold level stimulus d) a single stimulus followed immediately by a second stimulus

c) a threshold level stimulus

Which part of the neuron is responsible for generating a nerve impulse? a) dendrite b) Nissl substance c) axon d) soma

c) axon

The majority of the cranial nerves attach to the: a) spinal cord. b) cerebellum. c) brain stem. d) forebrain.

c) brain stem.

Which type of sensory receptor allows us to feel an insect landing on our skin? a) chemoreceptor b) nociceptor c) mechanoreceptor d) thermoreceptor

c) mechanoreceptor

Which of the meninges is a delicate connective tissue membrane that clings tightly to the brain like cellophane wrap following its every convolution? a) periosteal layer of the dura mater b) meningeal layer of the dura mater c) pia mater d) arachnoid mater

c) pia mater

Which type of white matter fiber tract connects the cerebrum to lower centers, like the spinal cord? a) corpus callosum b) association fibers c) projection fibers d) commissures

c) projection fibers

Which functional area of the brain is responsible for our level of awareness and alertness? a) limbic system b) Broca's area c) reticular activating system d) frontal eye fields

c) reticular activating system

The thickest and longest nerve in the body is the: a) obturator nerve. b) pudendal nerve. c) sciatic nerve. d) femoral nerve.

c) sciatic nerve.

Which of the following lists the hierarchy of motor control from lowest to highest level of control? a) projection level, precommand level, segmental level b) segmental level, precommand level, projection level c) segmental level, projection level, precommand level d) precommand level, projection level, segmental level

c) segmental level, projection level, precommand level

Somatic reflexes activate: a) glands. b) smooth muscle. c) skeletal muscle. d) cardiac muscle.

c) skeletal muscle.

Which of the following is NOT used to classify sensory receptors? a) the type of stimulus they detect b) structural complexity c) the number of dendritic endings present d) location

c) the number of dendritic endings present

Which cranial nerve transmits information about our sense of equilibrium? a) abducens b) optic c) vestibulocochlear d) vagus

c) vestibulocochlear

Which ion channel opens in response to a change in membrane potential and participates in the generation and conduction of action potentials? a) mechanically gated channel b) ligand-gated channel c) voltage-gated channel d) leakage channel

c) voltage-gated channel

The film terminal and spinal nerves in the lumbar and sacral regions are called the

cauda equina

All of the following are structures of the limbic system except the ________. amygdaloid nucleus hippocampus cingulate gyrus caudate nucleus

caudate nucleus

The dorsal root ganglia mainly contain axons of sensory neurons. cell bodies of motor neurons. cell bodies of sensory neurons. synapses. axons of motor neurons.

cell bodies of sensory neurons.

The dorsal root ganglion contains the__of__neurons

cell bodies, sensory

Interventricular Foramen

channel in which lateral ventricals communicate with third ventricle

Bell's palsy is ________.

characterized by paralysis of facial muscles

Chemical synapses that release the neurotransmitter ACH are known as ____________ synapses

cholinergic

Where is cerebrospinal fluid produced?

choroid plexus

the dura mater attaches itself at its base to the skeletal system through the

coccygeal ligament

1

coccygeal nerves

a

cognition is best described as _______. a. recognizing, processing, planning, and responding to stimuli b. a reversible and normal suspension of consciousness c. the ability to comprehend and produce words d. encoding and storing learned info in our neural circuitry

The "branches" that enable a single neuron to communicate with several other cells are called...

collaterals

The end of an axon branches into what?

collaterals

The white matter of the spinal cord is divided into regions called...

columns

The sciatic nerve is a combination of which two nerves?

common fibular and tibial

Sensory pathways

conducts information from peripheral receptors to processing centers in the brain

interneurons / association neurons

connect sensory to motor neurons 90% of neurons in the body

Ventricles

connected to one another and to the central canal of the spinal cord; hollow ventricular chambers are filled with cerebrospinal fluid and lined by ependymal cells

meninges

connective tissue coverings that encircle the brain & spinal cord

The Brachium of the superior colliculus ?

connects it to the lateral geniculate nuclei in the thalamus.

Which of the following is NOT associated with the primary motor cortex?

conscious control of skeletal muscles origin of corticospinal tracts post-central gyrus cell bodies of pyramidal neurons

cerebral white matter

consists of myelinated and unmyelinated axons in three types of tracts: association tracts, commissural tracts and projection tracts

epithalamus

consists of the pineal gland and habenular nuclei.

anterior or ventral root

contain axons of motor neurons, which conduct impulses from the CNS to effector organs and cells

association tracts

contain axons that conduct nerve impulses between gyri in the same hemisphere.

Commissural tracts

contain axons that conduct nerve impulses from gyri in one cerebral hemisphere to corresponding gyri in the other cerebral hemisphere. - Three important groups of commissural tracts are the corpus callosum (the largest fiber bundle in the brain, containing about 300 million fibers), anterior commissure, and posterior commissure.

Projection tracts

contain axons that conduct nerve impulses from the cerebrum to lower parts of the CNS (thalamus, brainstem, or spinal cord) or from lower parts of the CNS to the cerebrum.

Primary Motor Cortex

contain large neurons known as pyramidal cells in precentral gyri that allow us to consciously control the precise or skilled voluntary movements of our skeletal muscles

A mixed nerve is one that

contains both sensory and motor fibers

What is contained in the Inferior Brachium?

contains fibers on the way to the medial geniculate nuclei on the way to the auditory system

posterior or dorsal roots

contains only sensory fibers, which conduct nerve impulses from the periphery into the CNS

Fourth Ventricle

continuous with third ventricle via cerebral aquaduct; lies in the hindbrain dorsal to the pons and superior medulla; continuous with the central canal of the spinal cord inferiorly; marked by three openings (paired apertures [in side walls] and median aperture [in its roof]); apertures connect ventricles to subarachnoid space

cervical

contol upper limbs

what do satellite cells do?

control environment around neurons

Sciatica has no direct affect on ______.

control of the adductor longus

Motor Areas of Cerebral Cortex

control voluntary movement; lie in the posterior part of the frontal lobes

Somatic nervous system

controls skeletal muscles

lumbar

controls the lower limbs

The terminal portion of the spinal cord is called the..

conus medullaris

axillary

crutch palsy is caused by damage to this nerve

In carpal tunnel syndrome, there may be tingling and numbness in the thumb due to compression of the ______.

cutaneous branches of the median nerve

Which of the following lists the hierarchy of motor control from lowest to highest level of control? a) Precommand level, projection level, segmental level b) Projection level, precommand level, segmental level c) Segmental level, precommand level, projection level d) Segmental level, projection level, precommand level

d) Segmental level, projection level, precommand level

Nerves that carry impulses toward the CNS only are ________. a) efferent nerves b) motor nerves c) mixed nerves d) afferent nerves

d) afferent nerves

Which part of the brain is the "executive suite" that controls almost all brain activity? a) diencephalon b) brain stem c) cerebellum d) cerebral cortex

d) cerebral cortex

Which reflex has a contralateral component? a) stretch b) tendon c) flexor d) crossed-extensor

d) crossed-extensor

Which of the following is NOT a correctly matched pair? a) spinal cord: inner gray matter b) superficial in the brain: gray matter c) gray matter: location of brain nuclei d) gray matter: myelinated axons

d) gray matter: myelinated axons

An inhibitory postsynaptic potential (IPSP) is associated with ________. a) lowering the threshold for an action potential to occur b) a change in sodium ion permeability c) opening of voltage-regulated channels d) hyperpolarization

d) hyperpolarization

Which of the following is NOT a feature of the major spinal cord tracts (pathways)? a) somatotopy b) decussation c) relay d) memory

d) memory

Which of the following does NOT help increase conversion of short-term to long-term memories? a) rehearsal b) your emotional state c) association d) memory consolidation

d) memory consolidation

Which of the choices below describes the ANS? a) sensory and motor neurons that supply the digestive tract b) sensory neurons that convey information from somatic receptors in the head, body wall, and limbs and from receptors from the special senses of vision, hearing, taste, and smell to the CNS c) motor fibers that conduct nerve impulses from the CNS to skeletal muscles d) motor fibers that conduct nerve impulses from the CNS to smooth muscle, cardiac muscle, and glands

d) motor fibers that conduct nerve impulses from the CNS to smooth muscle, cardiac muscle, and glands

Nerves that only carry impulses away from the central nervous system (CNS) are called: a) afferent nerves. b) mixed nerves. c) sensory nerves. d) motor nerves.

d) motor nerves.

In what way does the interior surface of a cell membrane of a resting (nonconducting) neuron differ from the external environment? The interior is ________. a) positively charged and contains more sodium b) positively charged and contains less sodium c) negatively charged and contains more sodium d) negatively charged and contains less sodium

d) negatively charged and contains less sodium

Potentially damaging stimuli that result in pain are selectively detected by ________. a) interoceptors b) photoreceptors c) proprioceptors d) nociceptors

d) nociceptors

Which of the following cranial nerves carries only sensory information? a) oculomotor b) abducens c) trigeminal d) olfactory

d) olfactory

motor pathways

delivering information from the CNS motor control centers to the effector organs

pain receptors are the

dendrites of sensory neurons

The region of the body surface monitored by a pair of spinal nerves is known as a(n) __________. input domain dermatome segment dermal band

dermatome

motor

descending tracts

The phrenic nerve serves the __________.

diaphragm

Includes the thalamus, hypothalamus, and epithalamus

diencephalon

The hyperalgesia that is common in phantom limb pain could be blocked if a new drug was developed that could prevent (without triggering any side-effects) the ______.

diffusion of calcium ions through NMDA receptors

which of the following occurs as descending inhibitory synapses develope

disappearance of the babinski response

The spread of nerve impulses from one neuron to several neurons is called...

divergence

neuroglial cells

do not produce action potentials 1/2 volume of the CNS divide rapidly to form tumors called gliomas

Which pair below is incorrect? a) cranial nerve VI: eye movement b) optic nerve: sensory c) cranial nerve III: pupillary constriction d) cranial nerve III: oculomotor nerve e) cranial Nerve IV: sensory

e) cranial Nerve IV: sensory

How different structures make up the limbic system? What links all these structures together?

eight structures make up the limbic system; the fornix links them together

The type of synapse where direct physical contact between the cells occurs is a(an)

electrical

motor

electrical signal arises in the precentral gyrus of the frontal lobe

brain waves

electrical signals involving brain neurons generating millions of nerve impulses (action potentials)

The sum of all chemical and electrical forces active across the cell membrane is known as the...

electrochemical gradient

Gyri

elevated ridges of tissue

schwann cells

encircle PNS axons each cell produces part of myelin sheath surrounding an axon in the PNS

Describe the components and operation of the flexor reflex.

encounter pain (step on a tack), up leg and back, spinal nerve, spinal cord by dorsal side, axon into gray matter, synapse with interneurons, white matter, spinal cord segments, different levels of motor neurons, down spinal cord, down leg, muscles contract

conus medullaris

end of spinal cord (point)

The connective tissue layer that covers Schwann cells is the __________. endoneurium epineurium perineurium endomysium

endoneurium

Which connective tissue layer directly surrounds each axon in a nerve?

endoneurium

the delicate connective tissue fibers that surround individual axons of spinal nerves comprise a layer called the

endoneurium

agonist

enhances a neurotransmitter

What cells line the ventricles of the brain? Choose one answer. a. astrocytes b. epithelial cells c. ependymal cells d. neurons

ependymal cells

Name the spaces which seperate the various layers of the meninges.

epidural space-between brain and dura; subdural space-between dura and arachnoid; subarachnoid space-between arachnoid and pia

Pressure, pain, and temperature receptors in the skin are ________.

esteroceptors

In a crossed-extensor reflex, if the right arm was grabbed it would flex and the left arm would ________.

extend

In a crossed-extensor reflex, if the right arm was grabbed it would flex and the left arm would ________. Choose one answer. a. also flex b. abduct c. extend d. adduct

extend

diencephalon

extends from the brain stem to the cerebrum and surrounds the third ventricle; it includes the thalamus, hypothalamus, and epithalamus.

motor

extrapyramidal tracts

A patient who received a blow to the side of the skull exhibits the following signs and symptoms on that side of the face: he is unable to close his eye, and the corner of his mouth droops. Which cranial nerve has been damaged?

facial

A patient who received a blow to the side of the skull exhibits the following signs and symptoms on that side of the face: he is unable to close his eye, and the corner of his mouth droops. Which cranial nerve has been damaged? Choose one answer. a. facial b. glossopharyngeal c. hypoglossal d. accessory

facial

The glossopharyngeal nerve is the only cranial nerve that contains sensory fibers.

false

A major nerve of the lumbar plexus is the ________.

femoral

Insula

fifth lobe of cerebral hemisphere; buried deep within the lateral sulcus and forms part of its floor; covered by portions of the temporal, parietal, and frontal lobes

sympathetic

fight or flight emergency

The ________ is a strand of fibrous tissue that provides longitudinal support as a component of the coccygeal ligament. conus medullaris ventral root cauda equina dorsal root filum terminale

filum terminale

The supportive fibrous strand of the pia mater is the...

filum terminale

satellite cells

flat cells in peripheral ganglia

Damage to the ulnar nerve could result in the inability to ______.

flex the wrist

The median nerve of the brachial plexus innervates the

flexor muscles of the foreamr

accidentally touching a hot burner on a stove elicits a __f

flexor reflex

what do schwann cells do?

form a myelin sheath called a neurilemma.

astrocytes

form blood brain barrier metabolize neurotransmitters regulate K+ balance structural support

ependymal cells

form epithelial membrane lining cerebral cavities and central canal produce CSF

Cerebral Hemispheres

form the superior part of the brain; account for 83% of total brain mass; most conspicuous part of brain; entire surface marked by gyri, seperated by sulci; each has 3 basic regions (superficial cortex of gray matter, an internal white matter, and basal nuclei [islands of gray matter situated deep within the white matter])

There are__major plexuses of the spinal nerves

four

ventricles

four CSF-filled cavities within the brain

Which of the following is the conducting region of the neuron? a) Axon b) Dendrites c) Ganglia d) Neurofibrils

a) Axon

Which of the following is true of axons? a) Each neuron has a single axon. b) Each dendrite may have occasional branches along its length, which are called axons. c) Each axon may have occasional branches along its length, which are called dendrites. d) Each neuron has hundreds of axons.

a) Each neuron has a single axon.

__________ is a progressive degenerative disease of the basal nuclei that affects the dopamine-secreting pathways. a) Parkinson's disease b) Huntington's disease c) mad cow disease d) Alzheimer's disease

a) Parkinson's disease

Which of the following PNS neuroglia help to form myelin sheaths around larger nerve fibers in the PNS? a) Schwann cells b) Oligodendrocytes c) Astrocytes d) Satellite cells

a) Schwann cells

Which of the following allows us to consciously control our skeletal muscles? a) The somatic nervous system b) The sympathetic division of the autonomic nervous system c) The parasympathetic division of the autonomic nervous system d) The involuntary nervous system

a) The somatic nervous system

pineal gland

about the size of a small pea and protrudes from the posterior midline of the third ventricle - onsidered part of the endocrine system because it secretes the hormone melatonin

The cranial nerve with a cervical origin (spinal cord) is the ________.

accessory

consider the steps of a reflex arc. Which step follows information processing?

activation of a motor neuron

Which is the FIRST stem in the activation of a reflex arc?

activation of a receptor

What is a function of the spinal cord?

acts as an important reflex center

medullary rhythmicity area of the respiratory center

adjusts the basic rhythm of breathing.

Chemical synapses that release the neurotransmitter norepinephrine are known as _______________ synapses.

adrenergic

Sensory information is brought to the CNS by means of the __________ fibers.

afferent

Nerves that carry impulses toward the CNS only are ________.

afferent nerves

prefrontal cortex (frontal association area)

an extensive area in the anterior portion of the frontal lobe that is well-developed in primates, especially humans - This area has numerous connections with other areas of the cerebral cortex, thalamus, hypothalamus, limbic system, and cerebellum. - concerned with the makeup of a person's personality, intellect, complex learning abilities, recall of information, initiative, judgment, foresight, reasoning, conscience, intuition, mood, planning for the future, and development of abstract ideas

Terminal Arborization

an extensive complex of fine branches. Each branch ends in a synaptic knob (terminal button), a little swelling that forms a junction (synapse14) with the next cell. It contains synaptic vesicles full of neurotransmitter. In autonomic neurons, however, the axon has numerous beads called varicosities along its length (see fig. 11.21). Each varicosity contains synaptic vesicles and secretes neurotransmitter.

What is least descriptive of a the vagus nerve?

an inflamed vagus nerve causes Bell's palsy

filum terminale

anchor spinal cord in postion (coverings of nerves)

epidural

anesthesia outside dural space to block/numb the spinal nerve

olfactory

anosmia

Premotor Cortex

anterior to the precentral gyrus in the frontal lobe; controls learned motor skills of a repetitious or patterened nature; coordinates movement of several muscle groups simultaneously or sequentially; involved in planning of movements that deepend on sensory feedback

he subarachnoid space lies between what two layers of meninges? Choose one answer. a. dura and epidura b. arachnoid and epidura c. arachnoid and pia d. arachnoid and dura

arachnoid and pia

Which protective covering of the brain provides passageways for cerebrospinal fluid (CSF) to drain into the superior sagittal sinus?

arachnoid mater membranous part of the dura mater periosteal part of the dura mater pia mater

All of the following are true of polysynaptic reflexes, except that they have reverberating circuits that prolong the reflexive motor response. are arranged according to dermatomes. involve reciprocal innervation. are intersegmental in distribution. involve pools of interneurons.

are arranged according to dermatomes.

Astrocytes

are the most abundant glial cells in the CNS and constitute over 90% of the tissue in some areas of the brain. They cover the entire brain surface and most nonsynaptic regions of the neurons in the gray matter of the CNS. They are named for their many-branched, somewhat starlike shape. They have the most diverse functions of any glia:

The first three cranial nerves

are the olfactory, optic, and oculomotor nerves

Sensory Areas

area concerned with conscious awareness of sensation; occur in the parietal, insular, temporal, and occipital lobes

sensory

ascending tracts

the axons in the white matter of the spinal cord that carry sensory information up toward the brain are organized into

ascending tracts

Classify a fiber tract that communicates between the left prefrontal lobe and the left parietal lobe.

association fibers

4 neuroglial cells in CNS

astrocytes oligodendrocytes microglia ependymal

reflexes

automatic responses to change

sympathetic parasympathetic enteric

autonomic is divided into

The visceral motor system that provides automatic, involuntary regulation of smooth and cardiac muscle and glandular secretions is the...

autonomic nervous system

A student nurse is instructed to administer an IM in injection in the upper outer quadrant of the buttocks to

avoid injury to the sciatic nerve

axon

away from cell body

What is a benefit of a nerve plexus? a) A plexus does not allow for redistribution. b) Damage to one single branch of a plexus does not necessarily disrupt all motor information sent to a region. c) The dorsal ramus can be distributed to many areas. d) They provide a straight path from the spinal cord to target muscles.

b) Damage to one single branch of a plexus does not necessarily disrupt all motor information sent to a region.

Which of the following are gaps found along a myelin sheath? a) Neurilemma b) Nodes of Ranvier c) Telodendria d) Axolemma

b) Nodes of Ranvier

Choose the false statement about nerves. a) Nerves vary in size. b) The majority of a nerve's bulk is due to axons. c) Nerves consist of parallel bundles of myelinated and non-myelinated axons. d) Nerve axons are surrounded by a loose connective tissue layer called the endoneurium.

b) The majority of a nerve's bulk is due to axons.

Which of the following is not true of graded potentials? a) They can be called postsynaptic potentials. b) They increase amplitude as they move away from the stimulus point. c) They are short-lived. d) They can form on receptor endings.

b) They increase amplitude as they move away from the stimulus point.

Classify a fiber tract that communicates between the left prefrontal lobe and the left parietal lobe. a) commissural fibers b) association c) projection

b) association

The part of a neuron that conducts impulses away from its cell body is called a(n) ________. a) Schwann cell b) axon c) dendrite d) neurolemma

b) axon

Which part of the brain processes inputs received from the cerebral motor cortex, brain stem nuclei, and various sensory receptors, and then uses this information to coordinate balance, posture, and somatic movement problems? a) pons b) cerebellum c) diencephalon d) thalamus

b) cerebellum

Which connective tissue layer directly surrounds each axon in a nerve? a) epineurium b) endoneurium c) perineurium d) myoneurium

b) endoneurium

At age 79, Mrs. X is diagnosed with a disorder that severely impairs her logical judgment. Medical imaging techniques show that this has been most likely caused by brain damage in a ______. a) parietal lobe b) frontal lobe c) temporal lobe d) premotor cortex

b) frontal lobe

The middle primary brain vesicle, the mesencephalon, gives rise to which adult brain structure? a) cerebrum b) midbrain c) diencephalon d) medulla oblongata

b) midbrain

Spinal nerves are all classified as: a) sensory nerves. b) mixed nerves. c) afferent nerves. d) motor nerves.

b) mixed nerves.

The patellar "knee jerk" reflex is an example of a(n) ________. a) stress reflex b) stretch reflex c) extensor thrust reflex d) crossed-extensor reflex

b) stretch reflex

Which reflex is important for maintaining muscle tone? a) Golgi tendon reflex b) stretch reflex c) crossed-extensor reflex d) flexor reflex

b) stretch reflex

The knee-jerk reflex is an example of a: a) Golgi tendon reflex. b) stretch reflex. c) flexor reflex. d) superficial reflex.

b) stretch reflex.

The abducens nerve ________. a) exits from the medulla b) supplies innervation to the lateral rectus muscle of the eye c) relays sensory information from taste buds on the tongue d) if paralyzed, exhibits Bell's palsy

b) supplies innervation to the lateral rectus muscle of the eye

Which cranial nerve innervates most of the visceral organs? a) hypoglossal b) vagus c) accessory d) abducens

b) vagus

clostridium tetani aka lock jaw

bacteria enter the body through the axons of neurons disrupts motor neurons painful muscle spasms

antagonist

blocks the action of a neurotransmitter

vertebral column

bony vertebrae protect spinal cord

common integrative area

bordered by somatosensory, visual, and auditory association areas. - receives nerve impulses from these areas and from the primary gustatory area, primary olfactory area, the thalamus, and parts of the brain stem. - integrates sensory interpretations from the association areas and impulses from other areas, allowing the formation of thoughts based on a variety of sensory inputs. It then transmits signals to other parts of the brain for the appropriate response to the sensory signals it has interpreted.

Precentral Gyrus

borders the central sulcus anteriorly

Postcentral Gyrus

borders the central sulcus posteriorly

What type of nerve fibers are found in the ventral ramus of a spinal nerve?

both sensory and motor

spinal nerves are classified as mixed nerves because they contain

both sensory and motor fibers

Spinal nerves are both sensory and motor. purely sensory. interneuronal. involuntary. purely motor.

both sensory and motor.

Cortex

both the cerebral hemispheres and the cerebellum have this layer of gray matter

Which nerve plexus innervates the pectoral girdle and upper limbs? sacral plexus lumbar plexus cervical plexus brachial plexus

brachial plexus

The majority of the cranial nerves attach to the __________.

brain stem

Which brain structures are not involved in memory?

brain stem: midbrain, pons, medulla oblongata cerebellum

tract

bundle of axons and dendrites extending up and down the spinal cord without a connective tissue covering.

tract

bundles of axons in the CNS that are relatively uniform with respect to diameter, myelination and conduction speed

a

bundles of axons within a nerve are known as _______. a. fascicles b. the perineurium c. dendrites d. the endoneurium

d

bundles of white matter in the cerebrum are known as _______. a. nuclei b. ganglia c. nerves d. tracts

How are the spinal nerves connected to the spinal cord?

by the dorsal and ventral roots and sensory and motor axons

gray matter

integration center for spinal reflexes

Most neurons are..

interneurons

autonomic NS

involuntary nervous system

Inborn or intrinsic reflexes are ________.

involuntary, yet may be modified by learned behavior

Acquired reflexes are

learned responses

primary visual area

located at the posterior tip of the occipital lobe mainly on the medial surface - receives visual information and is involved in visual perception.

thalamus

measures about 3 cm (1.2 in.) in length and makes up 80% of the diencephalon, consists of paired oval masses of gray matter organized into nuclei with interspersed tracts of white matter - Relays almost all sensory input to the cerebral cortex. - Provides crude perception of touch, pressure, pain, and temperature. - Includes nuclei involved in movement planning and control.

__________ are receptors that can respond to changes in pressure.

mechanocreceptors

Which type of sensory receptor allows us to feel an insect landing on our skin?

mechanoreceptor

Longitudinal Fissure

medial; seperates the cerebral hemisphere

Which nerve is compressed in carpal tunnel syndrome?

median

In carpal tunnel syndrome, the __________ is compressed.

median nerve

The vital centers for the control of heart rate, respiration, and blood pressure are located in the ________.

medulla oblongata

hyperpolarization

membrane becomes more negative on the inside

depolarization

membrane becomes more positive on the inside

neurilemma

membrane in a nerve cell

th membranes surrounding and protecting the brain and spinal cord are the

meninges

The blood-brain barrier is effective against ________. Choose one answer. a. nutrients such as glucose b. metabolic waste such as urea c. anesthetics d. alcohol

metabolic waste such as urea

In the times of infection or injury the type of neuroglia that will increase in numbers is...

microglia

oligodendrocytes

most common glial cell forms myelin sheath

motor

most neurons decussate in the medulla oblongata

What is most descriptive of a descendign tract?

motor

The middle primary brain vesicle, the mesencephalon, gives rise to which adult brain structure?

midbrain, The term mesencephalon means "midbrain." As it develops from a primary brain vesicle to a secondary brain vesicle and finally an adult brain structure, it retains its name--the midbrain. Each of the other two primary brain vesicles divides to give rise to new secondary brain vesicles and adult brain structures (with new names). Note that encephalo- means "brain."

Hiccups could occur if there was irritation or damage to the ______.

motor branches of ventral rami associated with the C3-C5 region of the spinal cord

false

motor learning occurs in the substantia nigra of the basal nuclei. true or false?

Nerves that only carry impulses away from the central nervous system (CNS) are called __________.

motor nerves

b

motor neuron pools consist of _______. a. primary afferent neurons b. lower motor neurons c. upper motor neurons d. secondary afferent neurons

Ventral spinal cord roots contain ________ fibers, while the dorsal roots contain ________ fibers.

motor, sensory

Spinal nerves are all classified as __________.

mixed nerves

choroid plexuses

sites of CSF production - networks of capillaries (microscopic blood vessels) in the walls of the ventricles. The capillaries are covered by ependymal cells that form cerebrospinal fluid from blood plasma by filtration and secretion.

Somatic reflexes activate __________.

skeletal muscle

somatic

skeletal muscle contraction

The neuromuscular junction is a synapse where the postsynaptic cell is a(an)

skeletal muscle fiber

tendon reflex

monitors external tension produced during a muscular contraction and prevents tearing or breaking of the tendon

Describe the components and operation of the stretch reflex.

monosynaptic, knee jerk reaction, when muscle is stretched it contracts, shoots up leg to spinal nerve, sensory neurons go through dorsal portion of spine and motor neurons go through ventral portion of the spine

What area of the body does the obturator nerve serve? muscles of the posterior thigh abdominal muscles skin over the medial surface of the leg skin over the posterior surface of the leg

skin over the medial surface of the leg

A herniated lumbar disc could interfere with ______.

skin sensations from the lateral thigh skin sensations from the medial thigh adduction of the thigh

unmyelinated fibers

slow, small diameter fibers

microglia cells

small cells near blood vessels phagocytic give rise to macrophages and monocytes

autonomic / visceral

smooth and cardiac muscles and glands

The white matter of the spinal cord contains ________. Choose one answer. a. soma that have both myelinated and unmyelinated nerve fibers b. unmyelinated nerve fibers only c. myelinated nerve fibers only d. myelinated and unmyelinated nerve fibers

myelinated and unmyelinated nerve fibers

white

myelinated fibers appear

the white rams is the branch of a spinal nerve that consists of

myelinated preganglionic axons

white matter

myelinated processes

Third Ventricle

narrow; in the diencephalon; recieves communication from lateral ventricles; continuous with fourth ventricle

How many structures in the brain are involved with memory? Name them.

so far three: 1. prefrontal cortex 2. hippocampus 3. thalamus the cerebral hemispheres diencephalon: thalamus, hypothalamus, epithalamus

posterior gray horns

somatic and visceral sensory nuclei

the posterior gray horns of the spinal cord contain

somatic and visceral sensory nuclei

These nerves supply voluntary skeletal muscles, causing movement

somatic motor nerves

Anterior gray horns

somatic motor nuclei

What is the difference between a somatic reflex and a visceral reflex?

somatic reflex-contraction of a skeletal muscle, visceral reflex-response by smooth and cardiac muscle or gland

Addition of stimuli arriving at different locations of the nerve cell membrane is called...

spatial summation

Potentially damaging stimuli that result in pain are selectively detected by ________. Choose one answer. a. photoreceptors b. nociceptors c. proprioceptors d. interoceptors

nociceptors

Which receptors adapt most slowly?

nociceptors

Which receptors adapt most slowly? Choose one answer. a. pressure receptors b. touch receptors c. smell receptors d. nociceptors

nociceptors

The cell bodies of neurons in the gray matter of the spinal cord form groups called...

nuclei

Diagnostically, a needle is inserted between the third and fourth lumbar vertebreae into the subarachnoid space to

obtain a sample of cerebrospinal fluid

Which nerve does NOT belong to the sacral plexus? tibial nerve fibular nerve obturator nerve sciatic nerve

obturator nerve

Fas Axonal Transport

occurs at a rate of 20 to 400 mm/day and may be either anterograde or retrograde:

salutatory conduction

occurs in myelinated fibers depolarization only occurs at the nodes of ranvier impulses jumps from node to node faster

continuous conduction

occurs in unmyelinated fibers step by step depolarization

A fracture of the ethmoid bone could result in damage to which cranial nerve?

olfactory

Mixed cranial nerves containing both motor and sensory fibers include all except which of the following?

olfactory

Which of the following cranial nerves carries only sensory information?

olfactory

Primary Visual Cortex

on the extreme posterior tip of occipital lobe, but most of it is buried in the calcarine sulcus in medial aspect of occipital lobe; recieves visual information that originates on retina of the eye

lateral ventricle

one in each hemisphere of the cerebrum

light-gated

open and close due to light stimulation

gate channels

open and close in response to a stimulus causes excitability

ligand gated

open and close in response to chemical stimuli such as hormones and neurotransmitters

voltage gated

open in response to change in voltage

mechanically gated

open with mechanical stimulation

arachnoid mater

spider web arrangement of collagen fibers

Which structure is involved in the segmental level of motor control?

spinal cord

L2 L4

spinal cord ends at ___ in adults ___ in newborn

If the caudal portion of the neural tube failed to develop properly the cranial nerves would not form hindbrain would not be present telencephalon would cease development spinal cord may be affected

spinal cord may be affected

If the posterior portion of the neural tube failed to develop properly the ________. Choose one answer. a. spinal cord may be affected b. telencephalon would cease development c. cranial nerves would not form d. hindbrain would not be present

spinal cord may be affected

The __________ is part of the CNS and the __________ is part of the PNS brain; spinal cord spinal nerve; spinal cord spinal cord; spinal nerve cranial nerve; spinal nerve

spinal cord; spinal nerve

dorsal and ventral root of each spinal segment unite to form a lumbar enlargement. spinal nerve. spinal meninx. spinal ganglion. cervical enlargement.

spinal nerve.

plexus(es)

spinal nerves are grouped and sorted here

What is most descriptive of the cauda equina?

spinal nerves that emerge from the tail end of the spinal cord

What is the difference between a spinal reflex and a cranial reflex?

spinal reflex-synapse only occurs in spinal cord, cranial reflex-information travels up spinal cord and synapse occurs in brain

sensory

spinocerebellar

sensory

spinothalamic tract

The brachial plexus can be palpated at the lower lateral border of the sternocleidomastoid muscle. Injury to the brachial plexus could cause weakness or paralysis to all of the following EXCEPT the ______.

sternocleidomastoid muscle

Transduction refers to conversion of ________.

stimulus energy into energy of a graded potential

Transduction refers to conversion of ___________. Choose one answer. a. afferent impulses to efferent impulses b. presynaptic nerve impulses to postsynaptic nerve impulses c. receptor energy to stimulus energy d. stimulus information to nerve impulses

stimulus information to nerve impulses

vestibulocochlear

ototoxicity

What is a neurilemma?

outer nucleated cytoplasmic layer of schwann cells enclosing the myelin sheath

Lateral Sulcus

outlines the flaplike temporal lobe and seperates it from the parietal and frontal lobes

The knee-jerk reflex is an example of a __________.

stretch reflex

The patellar "knee jerk" reflex is an example of a(n) ________.

stretch reflex

The patellar "knee jerk" reflex is an example of a/an _________. Choose one answer. a. stretch reflex b. stress reflex c. extensor thrust reflex d. crossed-extensor reflex

stretch reflex

Which reflex is important for maintaining muscle tone?

stretch reflex

which of the following is an example of a somatic reflex?

stretch reflex

absolute refractory period

strong stimulus will not begin another action potential

The cerebrospinal fluid (CSF) circulates within the __________. subdural space subarachnoid space pia mater dura mater

subarachnoid space

to withdraw cerebrospinal fluid during a spinal tap, a needle is inserted into the

subarachnoid space

spinal tap lumbar puncture

subarachnoid space b/w L3-L5 samples CSF

Cerebrospinal fluid flows within the pia mater. arachnoid mater. dura mater. subarachnoid space. filum terminale.

subarachnoid space.

Samples of CSF for diagnostic purposes are normally obtained by placing the tip of a needle in the arachnoid mater. epidural space. cerebral ventricles. subarachnoid space. dura mater.

subarachnoid space.

Autonomic nervous system

subconscious control of visceral organs, including, smooth muscles, cardiac muscle, and glands.

Which of the following is not part of the basal nuclei? Choose one answer. a. globus pallidus b. lentiform nucleus c. substantia nigra d. putamen

substantia nigra

A shallow groove on the surface of the cortex is called a

sulcus

A shallow groove on the surface of the cortex is called a ________. Choose one answer. a. fissure b. furrow c. gyrus d. sulcus

sulcus

The trochlear nerve conveys proprioceptor impulses from the _______ to the brain. Choose one answer. a. superior rectus muscle b. medial rectur muscle c. lateral rectur muscle d. inferior rectus muscle

superior rectus muscle

relative refractory period

supra threshold stimulus will be able to start an action potential extra gates will have to open

Satellite Cells

surround the neurosomas in ganglia of the PNS. They provide electrical insulation around the soma and regulate the chemical environment of the neurons.

perineurium

surrounds a group of nerve fibers

Visual Association Area

surrounds the primary visual cortex and covers much of the occipital lobe; uses past visual experiences to interpret visual stimuli (color, form, and movement); complex processing involves entire posterior half of the hemisphere

denticulate ligaments

suspend the spinal cord in the middle of meninges

synaptic end bulbs

swollen axon tips

Addition of stimuli occurring in rapid succession at a single synapse is called...

temporal summation

The reflex that limits muscle tension is the __________ reflex. reciprocal flexor tendon stretch

tendon

A major relay station for sensory information ascending to the cerebral cortex. Contains many specialized nuclei.

thalamus

All processing at the circuit level going up to the perceptual level must synapse in the ________.

thalamus

true

perception occurs in the CNS and is a conscious awareness of a sensation. true or false

Three main levels of neural integration operate in the somatosensory system. Which level involves processing in the sensory areas of the cerebral cortex?

perceptual level

Which of the following does NOT occur as people age?

peripheral nerves die off

PNS

peripheral nervous system

If the premotor cortex of the brain is damaged, what is the person unable to do? What is the person still able to do?

person is unable to perform learned motor skills of a repetitious nature such as playing an instrument or typing, but they are still able to move

c

photoreceptors are found only in the _______. a. ear b. nose c. eye d. mouth

The most important branch of the cervical plexus is the __NERVE, WHICH INNERVATES THE DIAPHRAGM

phrenic

Which of the following nerves does not arise from the brachial plexus?

phrenic

Which of these cervical plexus nerves innervates the diaphragm? great auricular nerve phrenic nerve lesser occipital nerve transverse cervical nerve

phrenic nerve

The brachial plexus gives rise to all of the following nerves, except the median. ulnar. radial. musculocutaneous. phrenic.

phrenic.

the meninx that is firmly bond to neural tissue and deep to the other meninges is the

pia mater

The layer of the meninges in direct contact with the spinal cord is the pia mater. arachnoid. choroid plexus. dura mater. subarachnoid space.

pia mater.

Nuclei of cranial nerves V, VI, and VII are found in the ________. Choose one answer. a. cerebrum b. medulla c. pons d. midbrain

pons

Nuclei of cranial nerves V, VI, and VII are found in the ________. pons medulla cerebrum midbrain

pons (p. 448)

Vestibular Cortex

posterior part of the insula and adjacent parietal cortex; responsible for conscious awareness of balance (position of head in space)

Visceral Sensory Area

posterior to gustatory cortex; involved in conscious perception of visceral sensations (ex: upset stomach, full bladder)

This brain area associates experiences necessary for the production of abstract ideas, judgement, and conscience.

prefrontal cortex

Loss of ability to perform skilled motor activities such as piano playing, with no paralysis or weakness in specific muscles, might suggest damage to the

premotor cortex

local anesthetics

prevent opening of voltage gated sodium channels

The axons from this area form the major pyramidal (corticospinal) tracts.

primary (somatic) motor cortex

A patient is admitted to the rehabilitation unit five days after having a stroke. The nurse assesses his muscle strength and determines that he has right-sided weakness. There was damage to the localized areas of the _____cortex in the ____ cerebral hemisphere.

primary motor cortex, left

Which category of memory is involved when playing the piano? Choose one answer. a. motor b. emotional c. declarative d. procedural

procedural

12. Which type of white matter fiber tract connects the cerebrum to lower centers, like the spinal cord?

projection fibers; Projection fibers connect the cerebral cortex to the brain stem and spinal cord.

6. For our motor commands to travel toward our muscles, the signals must travel on

projection fibers; Projection fibers descend from brain toward the spinal cord

sensory neurons that monitor the position of skeletal muscles and joints are called...

proprioceptors

oculomotor

ptosis of the lids

motor

pyramidal tract

Two terms for the massive motor tracts serving voluntary movement are ________ and _________.

pyramidal tracts, aka corticospinal tracts

What is the effect organ in the knee - jerk or patellar tendon reflex?

quadriceps femoris muscle

Name and describe the function of each of the main branches of a spinal nerve.

rami, dorsal ramus, ventral ramus-most of the nerve fibers travel here, meningeal ramus-going to blood vessels of spinal cord, rami comunicantes-going to autonomic nervous system

sensory nuclei

receive and relay sensory information from peripheral receptors

Multimodal Association Areas

receive inputs from multiple sensory areas; send outputs to multiple areas, including the premotor cortex; allow us to give meaning to information received, store it as memory, compare it to pervious experience, and decide on action to take; each individiual perception come together (hear, see, touch, feel, and smell); can be divided into 3 parts (anterior association area, posterior association area, limbic association area)

Axon Hillock

from which the axon (nerve fiber) originates. The axon is cylindrical and relatively unbranched for most of its length, although it may give rise to a few branches called axon collaterals along the way, and most axons branch extensively at their distal end. An axon is specialized for rapid conduction of nerve signals to points remote from the soma. Its cytoplasm is called the axoplasm and its membrane the axolemma.12 A neuron never has more than one axon, and some neurons in the retina and brain have none. The Schwann cells and myelin sheath that enclose the axon in figure 12.4 are explained in the following section on neuroglia.

The central sulcus separates which lobes? Choose one answer. a. temporal from parietal b. frontal from parietal c. parietal from occipital d. frontal from temporal

frontal from parietal

4 lobes of the cerebral hemisphere

frontal, parietal, temporal, and occipital lobes - named after the bones they sit under.

What is a myelin sheath?

function is to protect the neuron, provide insulation, and increase the speed of impulse transmision

In the PNS, neuron cell bodies are located in...

ganglia

__________ are collections of neuron cell bodies associated with nerves in the peripheral nervous system (PNS).

ganglia

nodes of ranvier

gaps in myelinated sheath are called

sensory areas

receive sensory information and are involved in perception, the conscious awareness of a sensation - Sensory information arrives mainly in the posterior half of both cerebral hemispheres, in regions behind the central sulci. - In the cortex, primary sensory areas have the most direct connections with peripheral sensory receptors.

dendrite

go in cell body

The area of the spinal cord that surrounds the central canals and is dominated by the cell bodies of neurons and glia cells is the

gray matter

letter H or butterfly

gray matter in the spinal cord is shaped like

folia

gray matter of the cerebellar cortex made up of a series of slender, parallel ridges

horns

gray matter on each side of spinal cord is divided into regions called

unmyelinated fibers that innervate glands and smooth muscles in the body wall or limbs form the

gray ramus

cauda equina

group of nerves that emerge from the distal end of the spinal cord; horse's tail

5

growth of the spinal cord stops at age

Ridges of tissue on the surface of the cerebral hemispheres are called

gyri

neurons

have the capacity to produce action potentials

what do astrocytes do?

help in neuron development and control neural environment

hypoglossal

helps control the movements of the tongue; cranial nerve XII

Gray matter in the spinal cord is divided into

horns

cauda equina

horses tail hang from the end of the spinal cord

The first level of neural integration in the somatosensory system is the __________ level.

receptor

Which of the following is the correct simple spinal reflex arc?

receptor, afferent neuron, integration center, efferent neuron, effector

Which of the following is the correct simple spinal reflex arc? Choose one answer. a. receptor, afferent neuron, integration center, efferent neuron, effector b. effector, efferent neuron, integration center, afferent neuron, receptor c. effector, afferent neuron, integration center, efferent neuron, receptor d. receptor, efferent neuron, integration center, afferent neuron, effector

receptor, afferent neuron, integration center, efferent neuron, effector

What involuntary response to a stimulus is accomplished by these four structures - receptor, sensory neuron,motor neuron,effector organ?

reflex arc

true

reflexes are programmed, automatic, and rapid responses to stimuli. true or false?

Gustatory Cortex

region involved in perception of taste stimuli; located in insula deep to temporal lobe

d

regions of skin supplied by a spinal nerve for somatic sensation are known as _______. a. lines of cleavage b. the ABCDE rule c. the rule of nines d. dermatomes

Gray commisuresl

relay information from one side of the spin cord to the other before reaching its destination in the gray mater

What part of the brain is used in this accomodation pathway?

requires neural circuit to the cerebral cortex (occipital lobe and back)

Primary Somatosensory Cortex

resides in the postcentral gyrus of the parietal lobe, just posterior to the primary motor cortex; receive information from the general (somatic) sensory receptors in the skin and from proprioceptors (position sense receptors) in skeletal muscles, joints, and tendons; capable of spatial discrimination (identification of body region being stimulated)

what is the last step in the activation of a reflex arc?

response of an effector(muscle)

parasympathetic

rest and response returns the body to normal

This area is the main visceral control center of the body.

hypothalamus

common peroneal

if damaged, causes footdrop

Fast Retrograde Transport

returns used synaptic vesicles and other materials to the soma and informs the soma of conditions at the axon terminals. Some pathogens exploit this process to invade the nervous system. They enter the distal tips of an axon and travel to the soma by retrograde transport. Examples include tetanus toxin and the herpes simplex, rabies, and polio viruses. In such infections, the delay between infection and the onset of symptoms corresponds to the time needed for the pathogens to reach the somas.

Starting at the spinal cord, the subdivisions of the brachial plexus are (in order):

roots, trunks, divisions, cords

5

sacral nerves

Spinal nerves exiting the cord from the level of L4 to S4 form the ________.

sacral plexus

The process that conducts impulses along an axon at a high rate of speed is called ___________ conduction.

saltatory

what are the two neuroglial cells in the PNS

satellite cells and schwann cells

what forms a myelin sheath?

schwann cells in the PNS

The thickest and longest nerve in the body is the __________.

sciatic nerve

A fall or an improperly delivered gluteal injection could result in ________.

sciatica

what do ependymal cells do?

secrete spinal fluid

Which of the following is not a main level of neural integration in the somatosensory system?

segmental

Which of the following is not a main level of neural integration in the somatosensory system? Choose one answer. a. circuit b. receptor c. segmental d. perceptual

segmental

Which of the following lists the hierarchy of motor control from lowest to highest level of control?

segmental level, projection level, precommand level

motor / efferent

send motor nerve impulses to muscles and glands

olfactory

sense of smell

vestibulocochlear

senses hearing and balance

Which of the following is not a way that sensory receptors are classified?

sensitivity to a stimulus

in the CNS, the tracts that link the brain with the rest of the body are composed of

sensory and motor pathways

What are the three neurons classified by function?

sensory neurons, motor neurons, and interneurons

Name and describe the 5 functional components of a reflex arc.

sensory receptor-picks up stimulus, sencory neuron-picks up stimulus, integrading center-processes information, motor neuron-response to stimulus, effector-carries out response

afferent

sensory tracts ascend and are called

The dorsal root of a final nerve is the site for __neurons, whereas the ventral root is the site of __ neurons

sensory: motor

central sulcus

separates the frontal lobe from the parietal lobe.

lateral cerebral sulcus (fissure)

separates the frontal lobe from the temporal lobe.

parieto-occipital sulcus

separates the parietal lobe from the occipital lobe

Occipital Lobe

seperated from parietal lobe by the parietooccipital sulcus

Transverse Cerebral Fissure

seperates the cerebral hemispheres from the cerebellum below

Name the structures that make up the limbic system. sn, cg, pg, dg, h, a, h, anott

septal nuclei, cingulate gyrus, parahippocampal gyrus, dentate gyrus, hippocampus, amygdala, hypothalamus, anterior nucleus of the thalamus

when sensory information is relayed from one part of the brain to another, the pattern is called

serial processing

Why is the flexor reflex an example of an intersegmental reflex arc?

several different segments of spinal cord are involved

parallel processing is the neural circuit in which

several neurons or neuronal pools process the same information at one time

phrenic

severing this nerve requires the use of a ventilator

axons

impulses away from the cell body long thin cylindrical

oculomotor

in addition to mobbing the eyeball, this nerve raises the eyelid and constricts the pupil of the eye

What is the purpose of myelination?

increases the speed of the nerve impulse

shingles

infection of peripheral nerve by chicken pox virus causes severe pain, skin discoloration and a line of skin blisters

neuritis

inflammation of the nerves by injury, vitamin deficiency or poison

facial

inflammation of this nerve causes Bell's palsy, a paralysis of one side of the face

Describe the components and operation of the crossed extensor reflex.

information sent to opposite side of body

motor areas

initiate movements -Motor output from the cerebral cortex flows mainly from the anterior part of each hemisphere

Which of the following is not a role of the basal nuclei? Choose one answer. a. initiating protective reflex actions b. inhibiting unnecessary or antagonistic movements c. regulating attention and cognition d. controlling starting and stopping movements

initiating protective reflex actions

reflexive removal of a hand from a hot stove and blinking when the eyelashes are touched are examples of

innate reflexes

pia mater

inner layer directly covers the brain and spinal cord

femoral

innervates the inner thigh area

The phrenic nerve

innervates the major breathing muscle

Sulci

shallow grooves

Sulci

shallower grooves between folds of gyri

the brachial plexus innervates the

shoulder girdle and arm

the cervical enlargement of the spinal cord supplies nerves to the

shoulder girdle and arms

Brain

similar gray matter and white matter pattern as spinal cord; has additional regions of gray matter;

cerebrum

the "seat of intelligence." - provides us with the ability to read, write, and speak; to make calculations and compose music; and to remember the past, plan for the future, and imagine things that have never existed before. - Sensory areas are involved in the perception of sensory information; motor areas control muscular movement; and association areas deal with more complex integrative functions such as memory, personality traits, and intelligence. -Basal ganglia coordinate gross, automatic muscle movements and regulate muscle tone. Limbic system functions in emotional aspects of behavior related to survival.

What are the two most important parts of the brain in terms of regulating our emotions? What does each allow us to do?

the amygdala and the anterior part of the cingulate gyrus; the amygdala allows us to recognize angry or fearful facial expressions, assesses danger; the cingulate gyrus helps us to express our emotions through gestures and in resolving mental conflicts when we are frustrated

in the spinal cord the cerebrospinal fluid is found in

the central canal and subarachnoid space

d

the cerebellum functions in _______. a. biological rhythms b. learning, memory, and personality c. homeostatic functions such as breathing and heart rate d. the planning and coordination of movement

Which neural structures are found in the cerebral cortex? cell _________ d__________s u____________ a_________ but no f_________ t_________

the cerebral cortex contains neuron cell bodies, dendrites, and unmyelinated axons, but no fiber tracts

Cell bodies of the sensory neurons of the spinal nerves are located in ________. Choose one answer. a. sympathetic ganglia b. the thalamus c. the dorsal root ganglia of the spinal cord d. the ventral root ganglia of the spinal cord

the dorsal root ganglia of the spinal cord

The subdural space lies between the pia mater and the dura mater. the endosteum and the periosteum. the dura mater and the arachnoid mater. the arachnoid mater and the pia mater. the pia mater and the subarachnoid space.

the dura mater and the arachnoid mater.

the caudal equine is a complex of the spinal cord that includes

the film terminal and the ventral and dorsal doors caudal to the conus medullaris

why are the most complicated responses produced b polysynaptic responses?

the interneurons can control several different muscle groups

cerebellar hemispheres

the lateral wings/lobes of the cerebellum - Each hemisphere consists of lobes separated by deep and distinct fissures. - govern sub-conscious aspects of skeletal muscle movements. - contribute to equilibrium and balance.

Which part of the brain is our emotional brain?

the limbic system

The pyramidal tract is

the major motor tract that originates in the precentral gyrus

multipolar

the majority of the neurons in the CNS are

brain stem

the part of the brain between the spinal cord and the diencephalon; it consists of the (1) medulla oblongata, (2) pons, and (3) midbrain. - Extending through the brain stem is the reticular formation, a netlike region of interspersed gray and white matter.

Damage to the primary motor cortex results in a person losing ability to control which type of movement?

the person loses voluntary muscle control

a

the speed of nerve impulse transmission through the axon of a sensory neuron will be quickest in ______. a. a large diameter, myelinated axon b. axons with a greater receptive field c. a small diameter, unmyelinated axon d. axons that adapt to stimuli

tracts

the spinal cord promotes homeostasis by conducting nerve impulses along

the activity occurring in the golgi tendon organ involves

the stretching of the collagen fibers and stimulation of the sensory neuron

d

the vagus nerve is represented by roman numeral _______. a. V b. XII c. I d. X

vagus

the wanderer; widely distributed throughout thoracic and abdominal cavities

If the visual association area of the brain is damaged, what happens to that person's vision?

they can still see, but they don't know what they are looking at; but also they can apparently be blind if the visual association area is damaged, even thought that's not how I understood the book

Why are spinal nerves considered to be mixed nerves?

they have both sensory and motor axons

Septum Pellucidum

thin median membrane that seperated lateral ventricles

brain

thin outer shell of gray matter covers the surface

sciatic

this large nerve leaves or emerges from the distal end of the spinal cord and supplies the buttocks and posterior thighs

pupillary reflex

this reflex causes the pupils of the eyes to constrict (become smaller) in response to light

patellar tendon reflex

this reflex helps you maintain a standing posture; also called the knee-jerk reflex

baroreceptor reflex

this reflex helps your body maintain a normal blood pressure

gag reflex

this reflex involves the glossopharyngeal nerve and helps prevent food and water from going down the wrong way

babinski reflex

this reflex is elicited by stroking the sole of the foot; plantar flexion and curling of the toes are normal responses in an adult

12

thoracic nerves

An action potential only occurs if the membrane is lowered to the level known as...

threshold

The posterior side of the thigh, leg, and foot is served by the ________ nerve.

tibial

trigeminal

tic douloureux, a condition characterized by extreme facial and jaw pain, is caused by inflammation of this nerve; triggers include eating, shaving, and exposure to cold temperatures

sensory / afferent neurons

transport sensory information from skin, muscles, joints, sense organs and viscera to CNS

gray matter

unmyelinated

Motor Homunculi

upside - down caricatures representing the motor innervation of body regions

Helps to regulate blood pressure and digestion. Choose one answer. a. abducens b. vagus c. accessory d. olfactory e. vestibulocochlear

vagus

vestibulocochlear

vertigo

Problems in balance may follow trauma to which nerve?

vestibulocochlear

Serves the senses of hearing and equilibrium. Choose one answer. a. olfactory b. vestibulocochlear c. accessory d. vagus e. abducens

vestibulocochlear

Which cranial nerve transmits information about our sense of equilibrium?

vestibulocochlear

a

what functional brain system participates in memory, learning, emotion, and behavior? a. limbic system b. anterolateral system c. medial lemniscal system d. peripheral nervous system

a

what part of the brain is responsible for cognition? a. cerebral cortex b. thalamus c. reticular formation d. hypothalamus

c

what part of the motor pathway inhibits inappropriate movements? a. cerebellum b. occipital lobe c. basal nuclei d. primary motor cortex

a

what part of the spinal cord carries motor information from the brain? a. corticospinal tract b. posterior column c. spinocerebellar tract d. anterolateral system

c

what provides a link between the nervous system and the endocrine system? a. cerebellum b. pons c. hypothalamus d. thalamus

b

what reflex causes muscle tension? a. stretch reflex b. golgi tendon reflex c. crossed-extension reflex d. flexion (withdrawal) reflex

d

what type of fiber carries information from the frontal lobe of the right cerebral hemisphere to the occipital lobe of the same cerebral hemisphere? a. corpus callosum b. projection fibers c. commissural fibers d. associationfibers

d

what type of neuron contacts a muscle fiber and initiates a muscle contraction? a. sensory neuron b. interneuron c. upper motor neuron d. lower motor neuron

c

where are the cell bodies of lower motor neurons located? a. dorsal horn of spinal gray matter b. motor area of cerebral cortex c. anterior horn of spinal gray matter d. brainstem

a

where is the sensation of touch processed? a. somatosensory association cortex, or S2 b. primary somatosensory cortex, or S1 c. prefrontal cortex d. primary motor cortex

Describe the system by which the spinal nerves are named.

where the vertebrae above from which they exit

c

which brain nucleus serves as the body's "master clock"? a. caudate nucleus b. lentiform nucleus c. suprachiastmatic nucleus d. basal nucleus

d

which cranial nerve detects smell? a. trochlear nerve b. oculomotor nerve c. optic nerve d. olfactory nerve

a

which division detects stimuli of the general and special senses? a. somatic sensory division b. somatic motor division c. visceral motor division (ANS) d. visceral sensory division

a

which of the following carries sensory info only? a. posterior root b. anterior root c. anterior ramus d. posterior ramus

b

which of the following houses motor neurons? a. central canal of the spinal cord b. anterior root of the spinal nerve c. posterior root of the spinal nerve d. posterior root ganglion

b

which of the following should NOT cross the blood-brain barrier with ease? a. lipid based molecules b. large, polar molecules c. glucose d. carbon dioxide

d

which special sense does NOT travel through the thalamus at any point in its transmission? a. hearing b. vision c. gustation d. olfaction

descending tracts

white mater that carries motor information to the spinal cord

ascending tracts

white matter that carries information toward the brain

what do oligodendrocytes do?

wrap around axons to form myelin sheaths.

endoneurium

wraps around each nerve fiber

radial

wrist drop is caused by damage to this nerve

false

you reached into the freezer to grab a piece of ice. temperature information is carried to the brain by the posterior columns of the white matter in the spinal cord. true or false?

d

you've looked for your keys for the past ten minutes in several different places. the ability to keep track of the places you've already looked is stored in _______. a. short term (working) memory b. long-term memory c. long term potentiation d. immediate memory

Set Of Intelligence, Abstract Reasoning

Frontal Lobe

Somatic Motor Cortex

Frontal Lobe

Visual Area

Occipital Lobe

2 pairs of Nuclei just deep to the Periaqueductal Grey

Occulomotor Nuclear complex

the corticospinal tract.

The signals that control your handwriting travel down the spinal cord in

axon hillock

The simplest level of information processing takes place at the __________. a. dendrites b. soma c. axon hillock d. axon terminals

axon hillock

The site in the neuron where EPSPs and IPSPs are integrated is the a. chemical synapse. b. electrical synapse. c. synaptic terminal. d. dendritic membrane. e. axon hillock.

synaptic cleft

The small space between the sending neuron and the receiving neuron is the a. synaptic cleft. b. synaptic terminal. c. vesicle. d. calcium channel. e. neurotransmitter.

dendrites

carry messages into the cell body short, highly branched, unmyelinated

Which reflex is triggered when a stranger suddenly grasps your arm?

crossed-extensor

What are the four types of neurons classified by structure?

Anaxonic, bipolar, unipolar, multipolar

septum pellucidum

Anteriorly, the lateral ventricles are separated by a thin membrane

Depolarization

Any shift from the resting potential toward a more positive potential

What is the pupillary light reflex? -What is the direct response? -What is the consensual response?

Bilateral resonse, pupillary constrictionin response to the unilateral light stimulation -response of the light stimulated eye is referred to as the direct response -response of the unstimulated eye is referred to as the indirect or consensual response

chemically gated and postsynaptic

Binding of a neurotransmitter to its receptors opens __________ channels on the __________ membrane. a. voltage-gated; postsynaptic b. chemically gated; presynaptic c. voltage-gated; presynaptic d. chemically gated; postsynaptic

either depolarize or hyperpolarize

Binding of the neurotransmitter to its receptor causes the membrane to __________.

Person is diagnosed with disorder that impairs logical judgement. Brain damage where

Frontal lobe

Ions are unequally distributed across the plasma membrane of all cells. This job distribution creates an electrical potential difference across the membrane. What is this potential difference called?

Resting membrane potential

Functional area of brain responsible for our level of awareness and alertness

Reticular activating system

arachnoid mater and pia mater.

Cerebrospinal fluid fills in the space between

Executive Suite

Cerebrum

5

lumbar nerves

Potentially damaging stimuli that result in pain are selectively detected by ________.

nociceptors

There are 41 pairs of spinal nerves. Answer: True False

False

Substances that do cross the BBB

- A few water soluble substances, such as glucose, cross by active transport - others, such as creatine, urea and most ions cross very slow - lipid soluble substances: oxygen, carbon dioxide , alcohol and most anesthetic agents easily cross the barrier.

True or False: CNS nerve fibers regenerate because of the actions of Schwann cells.

False

blood-cerebrospinal fluid barrier

- Because the ependymal cells are joined by tight junctions, materials entering CSF from choroid capillaries cannot leak between these cells; instead, they must pass through the ependymal cells. - This barrier permits certain substances to enter the CSF but excludes others, protecting the brain and spinal cord from potentially harmful blood-borne substances.

cerebellum

- Compares intended movements with what is actually happening to smooth and coordinate complex, skilled movements. - Regulates posture and balance. - May have a role in cognition and language processing. - second only to the cerebrum in size - occupies the inferior and posterior aspects of the cranial cavity. - posterior to the medulla and pons and inferior to the posterior portion of the cerebrum - In superior or inferior views, the shape of the cerebellum resembles a butterfly

True or False: The sensory division of the PNS is also known as the efferent division.

False

True/False: Passive channels/leak channels are almost always closed

False

Cerebrospinal fluid

- a clear, colorless liquid that protects the brain and spinal cord from chemical and physical injuries. It also carries oxygen, glucose, and other needed chemicals from the blood to neurons and neuroglia. - CSF continuously circulates through cavities in the brain and spinal cord and around the brain and spinal cord in the subarachnoid space (between the arachnoid mater and pia mater).

Basal ganglia

- control automatic movements of skeletal muscles and muscle tone. - Deep within each cerebral hemisphere - three nuclei (masses of gray matter) that are collectively termed this - receive input from the cerebral cortex and provide output back to motor parts of the cortex. - the nuclei of the basal ganglia have extensive connections with one another. - A major function is to help regulate initiation and termination of movements. - help initiate and terminate some cognitive processes, such as attention, memory, and planning, and may act with the limbic system to regulate emotional behaviors.

midbrain or mesencephalon

- extends from the pons to the diencephalon - is about 2.5cm long - The cerebral aqueduct passes through the midbrain, connecting the third ventricle above with the fourth ventricle below. Like the medulla and the pons, the midbrain contains both tracts and nuclei. - Relays motor output from the cerebral cortex to the pons and sensory input from the spinal cord to the thalamus. - Superior colliculi coordinate movements of the eyeballs in response to visual and other stimuli, and the inferior colliculi coordinate movements of the head and trunk in response to auditory stimuli. Most of substantia nigra and red nucleus contribute to control of movement. - Contains nuclei of origin for cranial nerves III and IV.

What is the result of an UNCAL HERNIATION? -results in what? -can effect what type of fibers

- herniation through the tentorium cerebellum that surounds the midbrain. - Loss of sympathetic action and motor control of extraoccular eye muscles and the L.P - Can also effect C.S., C.P. and C.B. fibers

medulla oblongata

- is continuous with the superior part of the spinal cord; it forms the inferior part of the brain stem - begins at the foramen magnum and extends to the inferior border of the pons, a distance of about 3 cm (1.2 in.). - The medulla's white matter contains all sensory (ascending) and motor (descending) tracts that extend between the spinal cord and other parts of the brain. - Relays sensory input and motor output between other parts of the brain and the spinal cord. - Vital centers regulate heartbeat, blood vessel diameter, and breathing (together with pons) - Other centers coordinate swallowing, vomiting, coughing, sneezing, and hiccupping. - Contains nuclei of origin for cranial nerves VIII, IX, X, XI, and XII.

Broca's speech area

- located in the frontal lobe close to the lateral cerebral sulcus, is involved in the articulation of speech. - In most people, Broca's speech area is localized in the left cerebral hemisphere. - Neural circuits established between Broca's speech area, the premotor area, and primary motor area activate muscles of the larynx, pharynx, and mouth and breathing muscles. - The coordinated contractions of your speech and breathing muscles enable you to speak your thoughts.

Which of the following are motor areas of the cerebral cortex that lie in the posterior part of the frontal lobes and control voluntary movement?

-Broca's area; posterior association area; auditory areas; visual areas *primary motor cortex; premotor cortex; Broca's area; frontal eye field -primary motor cortex; premotor cortex; prefrontal cortex; gustatory cortex -primary somatosensory cortex; somatosensory association cortex; visual areas

What is the Argyll-Robertson Pupil. aka_______ -what is it -what causes it -Pupil action with the condition

-The prostitutes pupil -Pupils do not constrict with light stimulation (both direct and indirect) -caused by bilateral damage to the pretectal area (can be due to syphilis) -pupils CAN constrict durng accommodation for near vision (different pathway)

Types of Neuroglia

1) Oligodendrocytes 2) Ependymal cells 3) Microglia 4) Astrocytes 5) Schwann cells or neurilemmocytes 6) Satellite Cells

Three Fundamental Physiological Properties

1) Excitability (irritability). All cells are excitable—that is, they respond to environmental changes (stimuli). Neurons exhibit this property to the highest degree. 2) Conductivity. Neurons respond to stimuli by producing electrical signals that are quickly conducted to other cells at distant locations. 3) Secretion. When the electrical signal reaches the end of a nerve fiber, the neuron secretes a chemical neurotransmitter that crosses the gap and stimulates the next cell.

Regeneration of Nerve Fibers

1) In the normal nerve fiber, note the size of the soma and the size of the muscle fibers for comparison to later stages. 2) When a nerve fiber is cut, the fiber distal to the injury cannot survive because it is incapable of protein synthesis. Protein-synthesizing organelles are mostly in the soma. As the distal fiber degenerates, so do its Schwann cells, which depend on it for their maintenance. Macrophages clean up tissue debris at the point of injury and beyond. 3) The soma exhibits a number of abnormalities of its own, probably because it is cut off from the supply of nerve growth factors from the neuron's target cells (see Deeper Insight 12.3). The soma swells, the endoplasmic reticulum breaks up (so the Nissl bodies disperse), and the nucleus moves off center. Not all damaged neurons survive; some die at this stage. But often, the axon stump sprouts multiple growth processes as the severed distal end shows continued degeneration of its axon and Schwann cells. Muscle fibers deprived of their nerve supply exhibit a shrinkage called denervation atrophy. 4) Near the injury, Schwann cells, the basal lamina, and the neurilemma form a regeneration tube. The Schwann cells produce cell-adhesion molecules and nerve growth factors that enable a neuron to regrow to its original destination. When one growth process finds its way into the tube, it grows rapidly (3-5 mm/day), and the other growth processes are retracted. 5) The regeneration tube guides the growing sprout back to the original target cells, reestablishing synaptic contact. 6) When contact is established, the soma shrinks and returns to its original appearance, and the reinnervated muscle fibers regrow.

Function of Glia

1)They form a supportive framework for the nervous tissue. 2) They have extensions called perivascular feet, which contact the blood capillaries and stimulate them to form a tight seal called the blood-brain barrier. This barrier isolates the blood from the brain tissue and limits what substances are able to get to the brain cells, thus protecting the neurons. 3) They monitor neuron activity and signal blood vessels to dilate or constrict, thus changing the regional blood flow of the brain tissue in accordance with changing needs for oxygen and nutrients. 4) They convert blood glucose to lactate and supply this to the neurons for nourishment. 5) They secrete proteins called nerve growth factors (see Deeper Insight 12.3) that promote neuron growth and synapse formation. 6) They communicate electrically with neurons and may influence synaptic signaling between them. 7) They regulate the chemical composition of the tissue fluid. When neurons transmit signals, they release neurotransmitters and potassium ions. Astrocytes absorb these substances and prevent them from reaching excessive levels in the tissue fluid. 8) When neurons are damaged, astrocytes form hardened scar tissue and fill space formerly occupied by the neurons. This process is called astrocytosis or sclerosis.

What are the general functions of the nervous system?

1)receiving sensory data from inside and outside the body. 2) Processing information while using intelligence, memory, decision-making, ad then initiating a respond. 3) Responding by sending commands to muscles, organs, or glands.

How does the process of nerve regeneration occur in the PNS?

1. Trauma 2. Proximal portion seals off and swells, distal portion and myelin sheath disintegrate; neurileema survives. 3. Neurilemma and endoeurium form a regeneration tube. 4. Axon regeneration and re-myelination occurs. 5. innervation to effector is resorted.

The CSF contributes to homeostasis in three main ways

1. Mechanical protection CSF serves as a shock-absorbing medium that protects the delicate tissues of the brain and spinal cord from jolts that would otherwise cause them to hit the bony walls of the cranial and vertebral cavities. The fluid also buoys the brain so that it "floats" in the cranial cavity. 2. Chemical protection CSF provides an optimal chemical environment for accurate neuronal signaling. Even slight changes in the ionic composition of CSF within the brain can seriously disrupt production of action potentials and postsynaptic potentials. 3. Circulation CSF allows exchange of nutrients and waste products between the blood and nervous tissue.

The 4 kinds of info that sensory receptors trasmit and describe how CNS encodes each one

1. Modality - type of stimulus, encoded by "labeled line code", if signal comes from retina it must be a visual signal; all action potentials are the same. Labeled "sensory modalities" like taste, hearing, vision, pain i.e. coming from the tongue must be taste. 2. Location: •each sensory receptor receives input from its "receptive field" •sensory projection - brain identifies site of stimulation •receptive fields on the skin for instance are correlated with their sensory homunculus region on the postcentral gyrus. Smaller receptive fields have larger regions dedicated to it in the cortex (see Figure 14.23) Remember the sensory homunculus •The area of the cortex dedicated to sensations from specific body parts is proportional to the sensitivity of that body part (i.e. the number of sensory receptors per unit area) •It's a topographical representation of the sensory receptive fields of the body

Components of CN 3 (2 components)

1. Occulomotor Nucleus 2. Edinger-Westphal Nucleus

Weber's syndrome includes damage to the: (2 things) -Tie to corticobulbar fibers

1. Oculomotor nerve fibers: ipsilateral thrid nerve palsy 2.Pyramidal trat- results in contralateral UMN paralysis (spastic hemiplegia of the body) due to damage to the pyramidal fibers (corticospinal) descending in the crus cerebri. - May also be a UMN paralysis of a portion of the contralateral face due to interruption of corticobulbar fibers descending in the crus cerebri.

Unmyelinated fibers conduct impulses faster than myelinated fibers.

False

There are four association areas of the brain. Name each of them. Which one is the most complex?

1. prefrontal cortex 2. language areas 3. general (aka common) interpretation area 4. visceral association area

roots

2 bundles of axons which connect each spinal nerve to a segment of the cord

novocaine and lidocaine

2 local anesthetics

schwann and satellite cells

2 neuroglial cells of PNS

dura mater arachnoid mater pia mater

3 meninges

The 4 kinds of info that sensory receptors trasmit and describe how CNS encodes each one

3. Intensity- Intensity is encoded in 3 ways: •frequency of action potentials can increase or decrease •number of nerve fibres stimulated rises with intensity increase •which fibres are activated depends on weak or strong stimuli as nerve fibres can differ in their sensitivity and hence the threshold for which an action potential is generated Intensity; firing rate This can be achieved by the firing rate of the sensory receptor neuron (eg. olfactory receptors, somatosensory receptors) or the release rate of transmitter from the sensory receptor cell to activate the second order neuron (eg. rods and cones, hair cells, taste sensory receptor cells). Firing rate - greater response of pain from conscious awareness. 4. Duration (how long a stimulus lasts) is encoded by changes in the firing frequency of a nerve fibre over time Receptors exhibit sensory adaptation which means if the stimulus is prolonged then the firing of the neuron will get slower over time (e.g. jumping in to a hot bath). We become less aware of the stimulus. Receptors classified according to how quickly they adapt phasic receptor - burst of activity and quickly adapt (smell and hair receptors). May stop signaling even if stimulus continues.i.e. smell gas leak for several seconds, then the sensation fades in intensity even if the stimulus is still there. tonic receptor - adapt slowly, generates impulses continually (proprioceptors, nociceptors), slow dull ache.

The spinal cord consists of __________ segments, each associated with two pairs of nerve roots. 29 to 31 5 12 31

31

The spinal cord stops elongating at about __________ years of age. 4 15 10 2

4

How much of cerebrospinal fluid id produced daily?

500ml

What is a chemical synapse within the nervous system and how does it function?

A chemical synapse is a gap with presynaptic and postsynaptic neuroreceptors on either side which release or bind to chemicals when stimulated.

Gray matter

A collection of neuron cel bodies, neuroglia and unmyelinated axons

True

A dermatome is a nerve innervating a specific region in the skin.

cluster of neurosomas in the PNS.

A ganglion is a

True

A ganglion is a swelling along a nerve containing cell bodies of peripheral neurons.

Excitatory postsynaptic potential

A graded depolarization caused by the arrival of a neurotransmitter at the postsynaptic membrane

Inhibitory postsynaptic potential

A graded hyperpolarization of the postsynaptic membrane

Axon

A long cytoplasmic process capable of propogating an electrical impulse/action potential

Resistance

A measure of how much the membrane restricts ion movement

afferent and efferent fibers

A mixed nerve consists of both

neurotransmitter

A molecule that carries information across a synaptic cleft is a a. sending neuron. b. neurotransmitter. c. synaptic cleft. d. synapse. e. receiving neuron.

Current

A movement of charges to eliminate a potential difference

muscle fibers.

A muscle spindle contains mostly

False

A nerve fiber is enclosed in its own fibrous sleeve called perineurium

What is a plexus? Name the principal plexuses.

A network of nerves; brachial plexus, cervical plexus, lumbar plexus, sacral plexus

Neuroglandular junction

A neuron controls or regulates the activity of a secretory gland

flexor (withdrawal) reflex.

A nurse pricks your finger to type your blood. You flinch at the pain, pulling your hand back. This is called the

True

A stretch reflex is often accompanied by reciprocal inhibition.

Neuromuscular junction

A synapse between a neuron and a muscle

Define a synapse.

A synapse is the specific location where a neuron is functionally connected to another neuron or an effector.

What is required for an action potential to be generated

A threshold level depolarization

depolarization necessary to cause an action potential

A threshold stimulus is the a. depolarization necessary to cause an action potential. b. electrical current that crosses the synaptic cleft. c. hyperpolarization of an axon. d. peak of an action potential. e. resting potential.

Hyposecretion of the adrenal cortical hormones produces A) Addison disease B) Cushing syndrome C) autoimmune disease D) masculinization in females

A) Addison disease

Aldosterone secretion increases blood pressure. A) True B) False

A) True

Calcitonin increases excretion of calcium by the kidney. A) True B) False

A) True

Chronobiology is the study of body rhythms such as circadian rhythms. A) True B) False

A) True

Follicle stimulating hormone (FSH) and luteinizing hormone (LH) are gonadotropins. A) True B) False

A) True

Glucagon and insulin are released by the pancreas in response to changes in the internal environment. A) True B) False

A) True

Oxytocin can be used to minimize the risk of post partum hemorrhage. A) True B) False

A) True

Parathyroid and growth hormones are examples of protein-related hormones. A) True B) False

A) True

Releasing hormones from the hypothalamus control secretion from the anterior lobe of the pituitary gland; nerve impulses directly stimulate the axons of neurosecretory cells in the posterior lobe. A) True B) False

A) True

Steroid hormones activate specific genes which instruct the cell to synthesize specific compounds. A) True B) False

A) True

The parathyroid glands are located on the posterior surface of the thyroid gland. A) True B) False

A) True

Prostaglandins A) can be potent in very small concentrations B) are capable of affecting target cells far from the site of secretion C) are stored in large quantities in liver cells D) are primarily used to control contraction of smooth muscle

A) can be potent in very small concentrations

Endocrine glands secrete hormones A) directly into body fluids such as blood B) that are active only in the endoplasmic reticulum of cells C) whose concentrations are regulated by positive feedback mechanisms D) that reach some body surface after secretion

A) directly into body fluids such as blood

Striking the "funny bone" is actually stimulation of (or injury to) the ________.

ulnar nerve

Cranial Nerve VI

Abducens Nerve Major function: Control some of the muscles moving the eyeballs

Cranial Nerve XI

Accessory Nerve Major function: Control head and shoulder muscles

initial segment

Action potential propagation begins (is first generated at) what region of a neuron? a. myelin b. dendrite c. node d. initial segment

all of the answers

Active neurons need ATP to support which of the following? a. the recovery from action potentials b. the movement of materials from the soma by axoplasmic transport c. the synthesis of neurotransmitter molecules d. the movement of materials to the soma by axoplasmic transport e. All of the answers are correct.

Presynaptic facilitation

Activity at an axoaxonic synapse increases the amount of neurotransmitter released when an action potential arrives at the synaptic terminal

Weber's syndrome aka ___________

Alternating occulomotor hemiplegia

1 meter per second

Approximately how fast do action potentials propagate in unmyelinated axons in humans? a. 12 meters per second b. 0.1 meters per second c. 1 meter per second d. 120 meters per second

The subarachnoid space lies between what two layers of meanings?

Arachnoid and Pia

norepinphrine

Adrenergic synapses release the neurotransmitter a. norepinephrine. b. acetylcholine. c. serotonin. d. GABA. e. dopamine.

What two divisions can you split the PNS into and briefly describe them?

Afferent division - Brings sensory information to the CNS from receptors Efferent division - Carries motor commands from the CNS to muscles, glands, and adipose tissue (SA/ME = Sensory Afferent/Motor Efferent)

Afferent, interneuron and efferent limb of the Pupillary light reflex

Afferent limb- cranial nerve 2 (optic) Interneurons- pretectal nucleus Efferent Limb- cranial nerve 3 (Edinger-Westphal portion of the oculomotor Nerve):P.S.

reabsorbs the choline

After acetylcholinesterase acts, the synaptic terminal a. reabsorbs the acetate. b. reabsorbs the choline. c. reabsorbs the acetylcholine. d. pinches off and a new terminal grows. e. reabsorbs axoplasm.

four types of brain waves

Alpha, beta, theta and delta

In meningitis, CSF flow can be disrupted. bacteria can be the cause. inflammation of the meninges occurs. viruses can be the cause. All of the answers are correct.

All of the answers are correct.

Which of the following is true regarding an epidural block? It can provide sensory and motor anesthesia, depending on the anesthetic selected. It affects only the spinal nerves in the immediate area of the injection. It can provide mainly sensory anesthesia, depending on the anesthetic selected. It is commonly used as a method of pain control during labor and delivery. All of the answers are correct.

All of the answers are correct.

Axonal Transport

All of the proteins needed by a neuron must be made in the soma, where the protein-synthesizing organelles such as the nucleus, ribosomes, and rough endoplasmic reticulum are located. Yet many of these proteins are needed in the axon, for example to repair and maintain the axolemma, to serve as ion channels in the membrane, or to act in the synaptic knob as enzymes and signaling molecules. Other substances are transported from the axon terminals back to the soma for disposal or recycling. The two-way passage of proteins, organelles, and other materials along an axon is called axonal transport. Movement away from the soma down the axon is called anterograde transport and movement up the axon toward the soma is called retrograde transport.

Which processes are always part of a reflex arc? afferent action potential receptor activation efferent action potential All of these processes are part of every reflex arc

All of these processes are part of every reflex arc

What does the PNS consist of?

All the neural tissue outside the CNS

Schwann Cells

Also called neurilemmocytes, envelop nerve fibers of the PNS. In most cases, a Schwann cell winds repeatedly around a nerve fiber and produces a myelin sheath similar to the one produced by oligodendrocytes in the CNS. There are some important differences between the CNS and PNS in the way myelin is produced, which we consider shortly. In addition to myelinating peripheral nerve fibers, Schwann cells assist in the regeneration of damaged fibers, which also is discussed later.

__________ is a progressive degenerative disease of the brain in which beta-amyloid peptide deposits and neurofibrillary tangles appear and that ultimately results in dementia (mental deterioration).

Alzheimer's disease Huntington's disease mad cow disease Parkinson's disease Alzheimer's disease is a degenerative brain disease in which beta-amyloid peptide deposits and neurofibrillary tangles appear. Marked by a deficit of ACh, it results in slow, progressive loss of memory and motor control and increasing dementia. Alzheimer's patients represent nearly half of the people living in nursing homes. Between 5 and 15% of people over 65 develop this condition, and for up to half of those over 85 it is a major contributing cause in their deaths.

What are the series of events in a cholinergic synapse? (4)

An action potential arrives and depolarizes the synaptic terminals Extracellular calcium ions enter the synaptic terminal, triggering the exocytosis of ACh ACh binds to receptors and depolarizes the postsynaptic membrane ACh is removed by AChE

voltage-gated Ca2+ channels

An action potential releases neurotransmitter from a neuron by opening which of the following channels? a. voltage-gated Ca2+ channels b. voltage-gated K+ channels c. chemically gated Ca2+ channels d. voltage-gated Na+ channels

What are the four structural classifications of neurons and briefly describe each

Anaxonic - Have more than two processes, but axons cannot be distinguished from dendrites Bipolar neuron - Two processes, one dendrite and one axon, separated by the cell body Unipolar neuron/pseudounipolar neuron - A single elongate process with the cell body situated off to the side Multipolar neuron - Have more than two processes; A single axon and multiple dendrites

Microglia

Are small macrophages that develop from white blood cells called monocytes. They wander through the CNS, putting out fingerlike extensions to constantly probe the tissue for cellular debris or other problems. They are thought to perform a complete checkup on the brain tissue several times a day, phagocytizing dead tissue, microorganisms, and other foreign matter. They become concentrated in areas damaged by infection, trauma, or stroke. Pathologists look for clusters of microglia in brain tissue as a clue to sites of injury. Microglia also aid in synaptic remodeling, changing the connections between neurons during nervous system development.

What are dermatomes? How may dermatomes be used therapeutically?

Areas of the skin that are served by a particular spinal nerve; If you don't feel anything on one spot, there may be damage

-60mV

Around what transmembrane potential does threshold commonly occur? a. -70 mV b. -60 mV c. +60 mV d. -60 V

melatonin

As more melatonin is liberated during darkness than in light, this hormone is thought to promote sleepiness. Melatonin also appears to contribute to the setting of the body's biological clock.

Fiber that communicates between the left prefrontal lobe and the left parietal lobe

Association

Who likes to have the sole of his foot stroked?

Babinksi

Which Cranial Nerve lowers the eye and which one rises the eyelid.

CN3 keeps the eye open CN7 brings it down

Describe structure and function of the four types of glial cells within the CNS, and the two types of glial cells of the PNS.

CNS glial cells: Astrocytes are star like due to projections from their surface and help form the BBB, regulate tissue fluid composition, form structural network, assist neuronal development and occupy space of dying neurons. Ependymal cells are ciliated simple cuboid or columnar cells lining internal cavities of the brain and spinal cord to assist in the production of CSF. Microglia are typically small with branches representing smallest percentages of CNS glial cells and act as protectors to infection or remove harmful substances. Oligodendrocytes are large with bulbous body and slender extensions that en-sheath portions of axons creating a myelin sheath. It insulates and provides faster transport of signals along the axon. PNS glial cells: Satellite cells surround cell bodies of sensory neurons and regulate continuous exchange of nutrients and waste products between neurons and their environment. Neurolemmocytes or Schwann cells en-sheath PNS axons to form a myelin sheath and allow faster AP propagation within the PNS.

brain and spinal cord

CNS is made of

arachnoid villi

CSF is gradually reabsorbed into the blood through these fingerlike extensions of the arachnoid that project into the dural venous sinuses

Sensory (afferent) Division of CNS

Caries signals from various receptors (sense organs and simple sensory nerve endings) to the CNS. This pathway informs the CNS of stimuli within and around the body.

Somatic Sensory Division

Carries signals from receptors in the skin, muscles, bones and joints.

Motor (Efferent ) Division of CNS

Carries signals from the CNS to gland and muscle cells that carry out the body's reponses. Cells and organs that respond to commands from the nervous system are called effectors.

Visceral Sensory Division

Carries signals mainly from the viscera of the thoracic and abdominal cavities, such as the heart, lungs, stomach and urinary bladder.

Visceral Motor Division (Autonomic Nervous System, ANS)

Carries signals to glands, cardiac muscle, and smooth muscle. We usually have no voluntary control over these effectors, and the ANS operates at an unconscious level. The responses of the ANS and its effectors are visceral reflexes. The ANS has two further divisions: sympathetic and parasympathetic.

Somatic Motor division

Carries signals to the skeletal muscles. This output produces muscular contractions that are under voluntary control as well as involuntary contractions called somatic reflexes.

When calcium enters synaptic terminal,

Cause vesicles containing neurotransmitter molecules to fuse to the plasma membrane of the sending neuron

Excitatory neurotransmitters

Causes depolarization and promotes the generation of action potentials

Inhibitory neurotransmitters

Causes hyperpolarization and suppresses the generation of action potentials

What does CNS stand for?

Central Nervous System

Motor Command Center

Cerebellum

"Executive suite" of brain that controls almost all brain activity

Cerebral cortex

b

Cerebrospinal fluid circulates through the _______. a. dura mater b. subarachnoid space c. pia mater d. blood-brain barrier

Graded potentials/local potentials

Changes in the transmembrane potential that cannot spread far from the site stimulation

Explain the neuron characteristics of excitability, conductivity and secretion.

Characteristics of excitability: stimulation of a neuron depends on it's location and usually is the act of binding secreted neurotransmitters released from other neurons. Conductivity: Quickly moving electrical impulses along plasma membranes of neurons after stimulation, this can be local and short-lived (graded potentials) or self-propagating (action potentials) Secretion: Neurotransmitters released in response to conductive activity are selective - that is one neuron releases a particular response that either excites or inhibits it's target neuron or effector.

If a synapse involves a neurotransmitter what is it called?

Chemical

Which statement about coma is true? Choose one answer. a. Coma is defined as total unresponsiveness to stimuli for a long period of time. b. Coma is neurologically identical to syncope. c. Coma is rarely caused by damage to brain stem structures. d. During coma, brain oxygen consumption resembles that of a waking state.

Coma is defined as total unresponsiveness to stimuli for a long period of time.

Ralph sustained a leg injury in a bowling accident and had to use crutches. Unfortunately, he never took the time to learn how to use them properly. After two weeks of use, he noticed his fingers were becoming numb. Then he noticed his arms were getting weaker and had a tingling sensation. What could be his problem?

Compression of the radial nerve (in the region of the armpit) may cause temporary cessation of nervous transmission, often called "Saturday night paralysis."

Which statement regarding the endocrine system is false? A) Signaling by the endocrine system is just as precise as the signaling by the nervous system. B) The actions of a hormone usually take longer to occur than the actions of a neurotransmitter. C) Endocrine glands are important in growth, development, and reproduction. D) Hormones exert their effects only on cells near the site of secretion

D) Hormones exert their effects only on cells near the site of secretion

Insulin secretion is regulated by a negative feedback system sensitive to A) the level of glycogen in the liver B) intracellular levels of glucose C) increases or decreases in the number of insulin receptors D) blood glucose concentration

D) blood glucose concentration

The actions of cortisol includes all of the following except A) breakdown of stored protein to increase levels of circulating amino acids B) release of increased amounts of fatty acids for an energy source C) stimulation of gluconeogenesis D) conservation of water

D) conservation of water

Injury to or removal of the parathyroid glands is likely to result in A) reduced osteoclastic activity B) Cushing syndrome C) kidney stones D) hypocalcemia

D) hypocalcemia

Which substance is required for synthesis of thyroid hormones? A) calcium B) phosphate ions C) sodium D) iodide salts

D) iodide salts

What is the PNS responsible for?

Delivers sensory information to the CNS and carries motor commands to peripheral tissues and systems

Main receptive part of the neuron

Dendrite

What are the functions of these neuron structures: dendrites, axon, synaptic vesicles and neurofibrils?

Dendrites: receive input and transfer it to the soma (cell body) for processing. Axon: makes contact with other neurons and transmits signals to other neurons. Synaptic vesicles: contain neurotransmitters Neurofibrils: intermediate filaments (neurofilaments) combine to form neurofibrils that extend throughout the neuron and provide support.

What are the three groups neurotransmitters and neuromodulators can fall into functionally?

Direct effect on membrane potential Indirect effect on membrane potential Lipid-soluble gases that exert their effects inside the cell

limbic system

Encircling the upper part of the brain stem and the corpus callosum is this ring of structures on the inner border of the cerebrum and floor of the diencephalon - sometimes called the "emotional brain" because it plays a primary role in a range of emotions, including pain, pleasure, docility, affection, and anger

What are the four classes of opioids in the CNS?

Endorphins Enkephalins Endomorphins Dynorphins

What are the four types of neuroglia in the CNS and briefly describe their functions

Ependymal - Assists in producing, circulating, and monitoring cerebrospinal fluid Astrocyte - Maintains blood-brain barrier; provide structural support; regulate ion, nutrient, and dissolved gas concentrations; absorb and recycle neurotransmitters; repairing damaged neural tissue Oligodendrocyte - Myelinate CNS axons; provide structural support Microglia - Remove cell debris, wastes, and pathogens by phagocytosis

What cells line the ventricles of the brain?

Ependymal Cells

What are the three neuroglial cells in the CNS

Ependymal, Astrocytes, and Oligodendrocytes

dural sheath and vertebral bones

Epidural anesthesia is introduced in the epidural space between ___ to block pain signals during pregnancy.

Compare and contrast the action of excitatory and inhibitory neurotransmitters in developing postsynaptic potentials (graded potentials) in the receptive segment.

Excitatory neurotransmitters cause the inside of the neuron to become slightly LESS negative (or more positive) by binding to chemically gated channels that let in more Na+. The stimulus is localized and becomes weaker as it moves along the neuron membrane decreasing as it reaches the axon hillock. Inhibitory neurotransmitters cause the cell inside to become slightly MORE negative (or less positive) by binding to chemically gated channels that let Cl- in or K+ out or both. This lowers the stimulus in relation to the threshold needed to generate a nerve signal.

Which of the following best describes the cerebrum?

Executive Suite

Cranial Nerve VII

Facial Nerve Major function: Carry nerve impulses associated with taste, salivation and muscles of facial expression

David, an aspiring baseball player, was struck on the left side of his face with a fastball pitch. He was not wearing a safety helmet. His zygomatic arch was crushed, as well as parts of the temporal bone. Following the accident and reconstructive surgery, he noted that his left lower eyelid was still drooping and the corner of his mouth sagged. What nerve damage did he sustain?

Facial nerve damage on his left side

A joint and the muscle that moves that joint tend to be innervated by different nerves.

False

Anatomically, all general sensory receptors are encapsulated nerve endings.

False

Projection fibers in the brain mainly connect the right and left hemispheres. Answer: True False

False

Reciprocal inhibition means that while one sensory nerve is stimulated, another sensory neuron for synergistic muscles in the same area is inhibited and cannot respond.

False

The all-or-none phenomenon as applied to nerve conduction states that the whole nerve cell must be stimulated for conduction to take place.

False

The dorsal ramus consists only of motor fibers bringing information to the spinal cord.

False

The nodes of Ranvier are found only on myelinated, peripheral neuron processes.

False

The obturator nerve branches from the sacral plexus.

False

The peripheral nervous system (PNS) includes the brain and spinal cord.

False

What two primary factors determine the effectiveness of PNS axon regeneration?

First, the amount of damage Second, the distance between the site of damaged axon and structure it innervates.

A shallow groove on the surface of the cortex is called a ___

Fissure

What are the four steps in peripheral nerve regeneration?

Fragmentation of axon and myelin occurs in distal stump Schwann cells form cord, grow into cut, and unite stumps. Macrophages engulf degenerating axon and myelin Axon sends buds into network of schwann cells and then starts growing along cord of Schwann cells Axon continues to grow into distal stump and is enclosed by Schwann cells

If a person has a brain tumor, is it more likely to have developed from neurons or from glial cells? Why?

From glial cells. First they are more numerous so more chance of abnormal behavior and secondly they are capable of division and many mutations are the result of cell division. Tumors especially are a result of cell mechanisms defaulting during certain parts of mitosis and over replicating mutated cells which then spread to the rest of the body in various ways.

The central sulcus separates which lobes?

Frontal From Parietal

Motor Speech Area

Frontal Lobe

Premotor Area

Frontal Lobe

hemispheric lateralization - anatomy

Functional asymmetry - Although the brain is almost symmetrical on its right and left sides, subtle anatomical differences between the two hemispheres exist. For example, in about two-thirds of the population, the planum temporale, a region of the temporal lobe that includes Wernicke's area, is 50% larger on the left side than on the right side. This asymmetry appears in the human fetus at about 30 weeks of gestation. Physiological differences also exist; although the two hemispheres share performance of many functions, each hemisphere also specializes in performing certain unique functions.

Identify the three functional categories of neurons and where each is primarily located.

Functional classification of neurons is according to the direction the action potential travels relative to the CNS; sensory neurons, motor neurons, and interneurons. Sensory neurons (afferent): input from somatic and visceral receptors, most(not all) are unipolar and located outside the CNS within posterior root ganglia. Motor neurons (efferent): neurons of motor nervous system conducting motor output to both somatic and visceral effectors, all are multipolar and most cell bodies are inside the CNS. Interneurons (association) are all in the CNS. Get stimulation from many other neurons receive, process and store it then decide how to respond. Outnumber all other neurons,, est. that 99% of our neurons are interneurons and are generally multipolar.

List the distinguishing features of glial cells.

Glial cells are inside the CNS and PNS, they are more numerous and smaller than neurons and capable of mitosis. They don't transmit nerve signals but do assist neurons with functions and cooperate to protect neurons while organizing and supporting nervous tissue.

enteric NS

GI tract involuntary sensory and motor neurons

Select the statement that is most correct.

Ganglia associated with afferent nerve fibers contain cell bodies of sensory neurons.

elect the statement that is most correct. Choose one answer. a. The cell bodies of afferent ganglia are located in the spinal cord. b. Ganglia associated with afferent nerve fibers contain cell bodies of sensory neurons. c. The dorsal root ganglion is a motor-only structure. d. Ganglia are collections of neuron cell bodies in the spinal cord that are associated with efferent fibers.

Ganglia associated with afferent nerve fibers contain cell bodies of sensory neurons.

What kind of nucleus is the Occulomotor Nuclear Complex?

General Somatic Efferent

A reflex that causes muscle relaxation and lengthening in response to muscle tension is called a ________.

Golgi tendon reflex

Compare and contrast graded potentials and action potentials.

Graded potentials (local potentials) occur in the receptive (dendrites & cell bodies) due to opening of chemically gated channels that allow small ion amounts to cross the membrane and the altered charge may result in a change in polarization. Degree of change depends on how many molecules make it through and decreases intensity over distance-usually only lasting a short time. Action potentials (AP) are the result of voltage gated channels opening (not chemically gated ones like GP's) and require a threshold value to be reached. Voltage below this is not sufficient to create an AP but once the threshold value is reached a temporary reversal of polarity across the plasma membrane occurs. AP's are self propagated or transmitted and maintain intensity along the synaptic knob because of the successive opening of other voltage gated channels. AP's obey the "all or none" law but not all APs have the same intensity under the same conditions.

How does a graded potential (GP) differ from an action potential (AP) in terms of the types of channels involved and where it occurs in a neruon

Graded potentials occur in the dendrites and cell body when chemically gated channels open and the cell either becomes more or less polarized. GPs are usually short, minimal changes that decrease over distance. APs start with the first segment of an axon and move through voltage gated channels through the length of the axon. The voltage change is first positive then negative and is usually strong because enough charge must be present to maintain the potential.

Postsynaptic potentials

Graded potentials that develop in the postsynaptic membrane in response to a neurotransmitter

neurosomas, dendrites, and proximal parts of axons of neurons.

Gray matter contains

spinal cord

H shaped inner core surrounded by white matter

Unipolar Neurons

Have only a single process leading away from the soma. They are represented by the neurons that carry sensory signals to the spinal cord. They are also called pseudounipolar because they start out as bipolar neurons in the embryo, but their two processes fuse into one as the neuron matures. A short distance away from the soma, the process branches like a T into a peripheral fiber and a central fiber. The peripheral fiber begins with a sensory ending often far away from the soma—in the skin, for example. Its signals travel toward the soma, but bypass it and continue along the central fiber for a short remaining distance to the spinal cord. The dendrites of such a neuron are considered to be only the short receptive endings. The rest of the process, both peripheral and central, is the axon, defined by the presence of myelin and the ability to generate action potentials

What is the Substantia Niagra?

Home of neurons that use dopamine as their transmitter. (tyrosine derived. Black color is a byproduct of the reaction of dopamine synthesis.

propagation is faster in myelinated axons

How do action potential propagation speeds in myelinated and unmyelinated axons compare? a. Propagation is faster in myelinated axons. b. Propagation speeds are similar in both axon types. c. Propagation in myelinated axons is faster over short distances, but slower over long distances. d. Propagation is faster in unmyelinated axons.

b

How is an action potential propagated along an axon? a. Stimuli from the graded (local) potentials from the soma and dendrites depolarize the entire axon. b. An influx of sodium ions from the current action potential depolarizes the adjacent area. c. An efflux of potassium from the current action potential depolarizes the adjacent area.

sensory

I'm wiggling my toes

motor

I'm winking

A graded hyper polarization of the postsynaptic membrane is referred to as a(n)

IPSP

are local hyperpolarizations

IPSPs (inhibitory postsynaptic potentials) a. block the efflux of calcium ions. b. are local hyperpolarizations. c. are local depolarizations. d. increase membrane permeability to sodium ions. e. block the efflux of potassium ions.

an intersegmental reflex.

If a bee sting on the right thigh causes a quick involuntary reaction of the right arm, this would be an example of

How is the testing of reflexes used in the diagnosis of disease?

If a reflex is absent, there may be nerve or muscle damage

the motor end plate will be depolarized

If the axon terminal of a motor neuron suddenly became permeable to calcium ion, a. neurotransmitter release will be blocked. b. the motor end plate will be depolarized. c. the neuron will become unable to stimulate the muscle cell. d. the motor end plate will be hyperpolarized. e. the neuron will fire an action potential.

presynaptic neuron

In a synapse, neurotransmitters are stored in vesicles located in the __________.

reticular formation

In addition to the well-defined nuclei already described, much of the brain stem consists of small clusters of neuronal cell bodies (gray matter) interspersed among small bundles of myelinated axons (white matter). - The broad region where white matter and gray matter exhibit a netlike arrangement - extends from the upper part of the spinal cord, throughout the brain stem, and into the lower part of the diencephalon.

the previous axonal segment is refractory

In an unmyelinated axon, why doesn't the action potential suddenly "double back" and start propagating in the opposite direction? a. The extracellular sodium concentration is too low around the previous axonal segment for an action potential to be (re)generated. b. New action potential generation near the soma repels previously generated action potentials. c. The previous axonal segment is refractory. d. Positive charges only move in one direction.

Myelin in CNS and PNS

In both the PNS and CNS, a nerve fiber is much longer than the reach of a single glial cell, so it requires many Schwann cells or oligodendrocytes to cover one nerve fiber. Consequently, the myelin sheath is segmented. The gaps between the segments are called nodes of Ranvier25 (RON-vee-AY), and the myelin-covered segments from one gap to the next are called internodes (see fig. 12.4a). The internodes are about 0.2 to 1.0 mm long. The short section of nerve fiber between the axon hillock and the first glial cell is called the initial segment. Since the axon hillock and initial segment play an important role in initiating a nerve signal, they are collectively called the trigger zone.

The 2 occulomotor nerves exit through the ______________ fossa (which is apart of what system)

Interpeduncular Fossa Ventricular system

Myelin in CNS

In the CNS, each oligodendrocyte reaches out to myelinate several nerve fibers in its immediate vicinity. Since it is anchored to multiple nerve fibers, it cannot migrate around any one of them like a Schwann cell does. It must push newer layers of myelin under the older ones, so myelination spirals inward toward the nerve fiber. Nerve fibers of the CNS have no neurilemma or endoneurium.

Myelin in PNS

In the PNS, a Schwann cell spirals repeatedly around a single nerve fiber, laying down as many as a hundred compact layers of its own membrane with almost no cytoplasm between the membranes (fig. 12.7a). These layers constitute the myelin sheath. The Schwann cell spirals outward as it wraps the nerve fiber, finally ending with a thick outermost coil called the neurilemma24 (noor-ih-LEM-ah). Here, the bulging body of the Schwann cell contains its nucleus and most of its cytoplasm. External to the neurilemma is a basal lamina and then a thin sleeve of fibrous connective tissue called the endoneurium. To visualize this myelination process, imagine that you wrap an almost-empty tube of toothpaste tightly around a pencil. The pencil represents the axon, and the spiral layers of toothpaste tube (with the toothpaste squeezed out) represent the myelin. The toothpaste would be forced to one end of the tube, which would form a bulge on the external surface of the wrapping, like the body of the Schwann cell.

Taste (gustatory) Area

Insula

What is the function of the myelin sheath?

Insulation and transmission along the axon.

Intranuclear Ophalmoplegia Normal Conditions:

Internuclear axons (collaterals) of abducens neurons cross midline and travel in the contralateral MLF to the (contralateral) oculomotor neurons innervating the medial rectus - This allsowed for conjugate lateral eye movements , i.e. when the lateral rectus of one eye contracts the medial rectus of the contralateral eye also contracts

What are the three groups of sensory neurons and briefly describe each

Interoceptors - Monitors the digestive, respiratory, cardiovascular, urinary, and reproductive systems and provide sensations of distension, deep pressure, and pain Exteroceptors - Provide information about the external environment in the form of touch, temperature, or pressure sensations and the more complex senses of taste, smell, sight, equilibrium, and hearing Proprioceptors - Monitor the position and movement of skeletal muscles and joints

What is the CNS responsible for?

It is responsible for integrating, processing, and coordinating sensory data and motor commands

What does it mean to say that spinal cord pathways exhibit somatotropy?

It means that tract fibers are spatially arranged in a way that reflects the orderly mapping of the body. For example, in an ascending sensory tract, somatotropy refers to the fact that fibers transmitting inputs from sensory receptors in the superior parts of the body lie lateral to those conveying sensory information from inferior body regions.

What does it mean to say that spinal cord pathways decussate?

It means they cross from one side of the CNS to the other at some point along their journey.

After Joe has a stroke, his doctor asks Joe to touch his right pointer finger to his chin—but Joe is unable to move his right hand. However, when the doctor stimulates Joe's pointer finger with a painful stimulus, Joe's muscles quickly move his hand away from the stimulus. The doctor concludes that ______. the stroke caused damage to Joe's frontal eye field which interfered with his effort to touch his chin the stroke caused damage to Joe's right primary motor cortex the stroke caused damage to Joe's left premotor cortex based on the doctor's observations, none of the listed answers are correct conclusions

It's not the primary motor cortex. The primary motor cortex of the brain functions to control voluntary skeletal muscle activity via contralateral innervation. It's not the premotor cortex. The premotor cortex of the brain determines which voluntary skeletal muscle groups will be activated and how they will be used prior to stimulating the primary motor cortex. However, none of these answers are correct. Review central nervous system control of voluntary skeletal muscle contractions and compare it to reflex arc activation.

decussation of pyramids

Just superior to the junction of the medulla with the spinal cord, 90% of the axons in the left pyramid cross to the right side, and 90% of the axons in the right pyramid cross to the left side. - explains why each side of the brain controls movements on the opposite side of the body.

sodium and potassium ions can diffuse across the plasma membranes or all cells because of the presence of what type of channel

Leak channels

CN's and structure involved with the Midbrain: Level of the Superior Colliculus

Level of the superior colliculus and cranial nerve 3

Interneurons (associated Neurons)

Lie entirely within the CNS. They receive signals from many other neurons and carry out the integrative function of the nervous system—that is, they process, store, and retrieve information and "make decisions" that determine how the body responds to stimuli. About 90% of our neurons are interneurons. The word interneuron refers to the fact that they lie between, and interconnect, the incoming sensory pathways and the outgoing motor pathways of the CNS.

Influences velocity and duration of muscle contraction

Load placed on the muscle

Cranial Nerve 'zero'

Located anterior to the first nerves - Innervate the vomeronasal organs, which may have a function in detecting pheromones, chemical signals passed subconsciously from one individual to another. - Pheromones have effects on reproductive and social behaviours.

Which fissure separates the cerebral hemispheres?

Longitudinal Fissure

Unmyelinated Nerve Fibers

Many nerve fibers in the CNS and PNS are unmyelinated. In the PNS, however, even the unmyelinated fibers are enveloped in Schwann cells. In this case, one Schwann cell harbors from 1 to 12 small nerve fibers in grooves in its surface (fig. 12.8). The Schwann cell's plasma membrane does not spiral repeatedly around the fiber as it does in a myelin sheath, but folds once around each fiber and somewhat overlaps itself along the edges. This wrapping is the neurilemma (also called a mesaxon in unmyelinated nerve fibers). Most nerve fibers travel through individual channels in the Schwann cell, but small fibers are sometimes bundled together within a single channel. A basal lamina surrounds the entire Schwann cell along with its nerve fibers.

the anterior horns.

Many upper motor neurons synapse with lower motor neurons in

Sensory receptor that allows us to feel insect on skin

Mechanoreceptor

What is the most significantly tested eye muscle?

Medial Rectus Muscle

The vital centers for the control of heart rate, respiration, and blood pressure are located in the ___

Medulla

Define membrane potential.

Membrane potential is the difference in charge between the cytosol and interstitial fluid. Internally there is a more negative charge and externally a more positive charge. These differences are considered "membrane potential"

The brain stem consists of the ____

Midbrain, Medulla, and Pons

If a person suffers from menigitis (inflammation of the coverings around the brain) which type of glial cell usually replicates in response to the infection?

Microglia are cells that wander through the immune system and respond to abnormalities.

Mesencephalon gives rise to

Midbrain

Dendrites

Named for their striking resemblance to the bare branches of a tree in winter. Dendrites are the primary site for receiving signals from other neurons. Some neurons have only one dendrite and some have thousands. The more dendrites a neuron has, the more information it can receive and incorporate into its decision making. As tangled as the dendrites may seem, they provide exquisitely precise pathways for the reception and processing of neural information.

Accommodation Pathway elaborated

Near object--> retina--> optic nerve--> optic chiasm --> optic tract --> LGN of the thalamus --> occipital lobe of the cerebral cortex

Describe the distribution of substances between the inside and outside of a neuron.

Negatively charged phophate ions or organic molecules, negatively charged protein molecules and K+ are more concentrated inside the neuron. Na+ and Cl- are more concentrated outside the neuron in the interstitial fluid.

True

Nerve fibers in a given tract in the white matter are similar in origin, destination, and function.

Describe the structure of a nerve, including the three layers of connective tissue wrappings.

Nerves are cable like bundles of axons with three successive connective tissues; epineurium, perineurium and endoneurium.

Describe the three basic anatomic features common to most neurons.

Neurons are very diverse but have three structural features: 1. A soma (cell body) inside a plasma membrane with perikaryon (cytoplasm) surrounding nucleus and other organelles. 2. Dendrites, short processes that branch from the soma that receive electrical input and transfer it to the soma for processing. More dendrites = more information received. 3. Axon's or nerve fibers are longer processes that contact other neurons, glands or muscles. Their cytoplasm is called axoplasm and membrane axolemma, they may have side branches called collaterals with telodendria at the end with synaptic knobs.

reticular activating system

Neurons within the reticular formation have both ascending (sensory) and descending (motor) functions. - This part of the reticular formation consists of sensory neurons that project to the cerebral cortex - helps maintain consciousness and is active during awakening from sleep - The reticular formation's main descending function is to help regulate muscle tone, the slight degree of contraction in normal resting muscles.

posterior root ganglion; gray matter

Neurosomas of the posterior root are located in the ___, whereas neurosomas of the anterior root are located in the ___.

Molecule that carries info across a synaptic cleft is called a

Neurotransmitter

What does the presynaptic cell release into the synaptic cleft?

Neurotransmitters

What are the gray areas seen in the brain and spinal cord?

Nissl bodies (Rough endoplasmic reticulum and free ribosomes)

Epidural space around brain?

No, no space around brain

Name four other neurotransmitters

Norepinephrine Dopamine Serotonin Gamma-aminobutyric

Describe the receptors for smell and explain how they are stimulated

Olfactory receptors: •Are found in the olfactory mucosa in superior part of nose just below cribriform plate on 5cm2 of superior nasal concha •The olfaction receptors are 1st order bipolar neurons Olfactory cells (are neurons) •Have olfactory hairs that project from the dendrites •bind odor molecules (odorants) in thin layer of mucus •Have axons that pass through the cribriform plate •survive 60 days •Have supporting cells Physiology of smell: •Most odours contain a mixture of many different chemicals. These activate a range of different receptors (up to 1000). Thus we can distinguish up to 10,000 different odours. •Odorants bind to receptors on olfactory hairs •Binding of odorant opens ion channels in membrane for Na+ or Ca2+, depolarizes it and creates a receptor potential, this triggers an action potential that travels to the brain. •Receptors adapt quickly (sensory adaptation), due to synaptic inhibition in olfactory bulbs. i.e. odours can change in quality and significance depending on whether you are hungry, just eaten or ill.

Will opening Na+ channels cause the membrane potential to become more positive or more negative?

Opening Na+ channels will allow more Na+ to enter the cell and the cell will become less negative related to it's surroundings and become depolarized.

substance P

Opioids relieve pain by blocking the release of a. substance X. b. substance O. c. substance Q. d. substance P. e. None of the answers is correct.

Cranial Nerve II

Optic nerve Major function: Vision

Differentiate between somatic pain, visceral pain and referred pain

Pain is an unpleasant sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage •Nociceptors - or pain receptors, allow awareness of tissue injuries and are found in all tissues except the brain •Somatic pain is pain from the skin, muscles and joints. •Visceral pain is pain from the viscera, and can result from stretch, chemical irritants or ischemia (lack of blood flow) of viscera (poorly localized) •Injured tissues release chemicals that stimulate pain fibres (bradykinin, histamine, prostaglandin) Misinterpreted pain (referred pain): •brain "assumes" visceral pain is coming from skin •heart pain felt in shoulder or arm because both send pain input to spinal cord segments T1 to T5 •Results in part from convergence of neural pathways from sensory input on inter-neurons at the spinal cord segments T1-T5 and then this input following similar pathways to thalamus and cerebral cortex •Brain gets it wrong basically

Primary Sensory Cortex

Parietal Lobe

Progressive degenerative disease of the basal nuclei that affects the dopamine-secreting pathways

Parkinson's disease

Tremor at rest, shuffling gait, stooped posture, and expressionless face are characteristics of ________. spinal cord disease Parkinson's disease cerebellar disease Huntington's disease

Parkinson's disease

Tremor at rest, shuffling gait, stooped posture, and expressionless face are characteristics of ________. Choose one answer. a. cerebellar disease b. Huntington's disease c. spinal cord disease d. Parkinson's disease

Parkinson's disease

What is the pretectal area?

Part of the midbrain located in immediately rostral to the superior colliculus and contains the posterior commissure with adjacent pretectal nuclei. The pretectal nuclei project both uncrossed and crossed fibers (some via the posterior commissure) to both E.W. Nuclei of cranial III, resulting in constriction of BOTH PUPILS

Select the correct definition.

Pattern recognition allows us to see a familiar face.

Select the correct definition. Choose one answer. a. Spatial discrimination allows us to recognize textures. b. Magnitude estimation is the simplest level of sensation. c. Pattern recognition allows us to see a familiar face. d. Perceptual detection is the ability to detect how much stimulus is applied to the body.

Pattern recognition allows us to see a familiar face.

Identify and describe structures unique to neurons.

Perikaryon - the cytoplasm within the neuron cell body Chromatophilic substance: free and bound ribosomes that stain darkly and appear as gray matter. Dendrites: small processes that branch from cell body. Axons: nerve fibers with telodendria at the end tipped with synaptic knobs and synaptic vesicles that contain neurotransmitters.

What does PNS stand for?

Peripheral Nervous System

List and describe the four functional neuron segments, including the distribution of channels and pumps in each.

Plasma membrane of functional segments in a neuron: 1. receptive segment with dendrites and the cell body. chemically gated channels (cation channels, K+ channels and Cl- channels are here. 2. initial segment is composed of the axon hillock containing both voltage-gated Na+ channels and voltage-gated K+ channels 3. Conductive segment is equal to the length of the axon and brnaches called teodendria containing both voltage-gated channels and Ca2+ channels and Ca2+ pumps 4. transmissive segment with synapitic knobs and voltage-gated ca2+ channels and Ca2+ pumps.

Production of Myelin

Production of the myelin sheath is called myelination. It begins in the fourteenth week of fetal development, yet hardly any myelin exists in the brain at the time of birth. Myelination proceeds rapidly in infancy and isn't completed until late adolescence. Since myelin has such a high lipid content, dietary fat is important to early nervous system development. It is best not to give children under 2 years old the sort of low-fat diets (skimmed milk, etc.) that may be beneficial to an adult.

White matter fiber tract that connects the cerebrum to lower centers, like the spinal cord

Projection fibers

Action potential

Propogated changes in the transmembrane potential that affect an entire excitable membrane

Blood-brain barrier - function and anatomy

Protects brain cells from harmful substances and pathogens by preventing passage of many substances from blood into brain tissue - consists mainly of tight junctions that seal together the endothelial cells of brain capillaries, along with a thick basement membrane around the capillaries. - then, the processes of many astrocytes press up against the capillaries and secrete chemicals that maintain the permeability characteristics of the tight junctions.

Define resting membrane potential, and state its typical value for neurons.

RMP is the membrane potential (difference in charge in/out) in a cells that is in a resting state - or in other words ready to become excited. The typical value of a neuron at RMP is -70mV but can range from -40mV to -90mV.

saltatory propagation

Rapid impulse conduction from "node" to "node" is called a. continuous propagation. b. synaptic transmission. c. spatial propagation. d. saltatory propagation. e. divergent propagation.

List and identify the different types of somatosensory receptors

Receptor types can be classified according to whether the dendrites are wrapped in CT or glial cells (encapsulated nerve endings) or (unencapsulated nerve endings) Unencapsulated receptor types include: Free nerve endings - for pain (nociceptors) and temperature (thermoreceptors such as cold receptors that respond to falling temps and warm receptors that respond to rising temps) Tactile (Merkel) discs (flattened)- associated with cells at base of epidermis. Hair receptors- monitor movement of hair Encapsulated receptor types include: tactile corpuscles (meisners corpuscles) (Phasic) - light touch and texture Tall/ovoid to pear shaped and move upward through a mass of schwann cells krause end bulb (phasic) - tactile; in mucous membranes Ovoid with a CT layer around a sensory nerve fibre lamellated corpuscles (pacinian corpuscles) (phasic) - large, onion like in cross section deep pressure, stretch, tickle and vibration concentric layers of connective tissue ruffinicorpuscles (tonic) - heavy touch, pressure, joint movements and skin stretching Flattened elongated capsules

What is the function of receptors?

Receptors are specialized nervous system structures that monitor changes in both internal and external environment called stimuli.

How does action potential move along a myelinated axon?

Saltatory conduction/Jumping in between nodes of ranvier of the myelinated axon

What shortens during muscle contraction

Sarcomere

What are the two types of neuroglia in he PNS and briefly describe their functions

Satellite cells - Regulate O2, CO2, nutrient, and neurotransmitter levels around neurons in ganglia Schwann cells - Surrounds all axons in PNS; responsible for myelination of peripheral axons; participates in repair after injury

After axonal injury, regeneration in peripheral nerves is guided by ________.

Schwann cells

PNS neuroglia that forms myelin sheaths around larger nerve fibers in PNS

Schwann cells

what forms a neurilemma?

Schwann cells

thalamus.

Second-order neurons synapse with third-order neurons in the

Lowest to highest

Segmental, projection, precommand

Motor (efferent) Neurons

Send signals predominantly to muscle and gland cells, the effectors. They are called motor neurons because most of them lead to muscle cells, and efferent neurons to signify signal conduction away from the CNS.

Define sensation and describe its process

Sense organ - A structure composed of nerve tissue and other tissues that enhance its response to a certain type of stimulus. Main purpose of sensory receptors is transduction, conversion of one form of energy to another. The transducer is the device that converts the energy ie sense organ. Receptor potential - the local electrical change from a stimulus on a neuron. 1.Define sensation and describe its process Sensation: •Conscious or subconscious awareness of changes in the external or internal environment •Sensory impulses may only reach the level of the spinal cord (e.g. stretch reflex), the lower brain stem (e.g. reflexes like blood pressure) or the cerebral cortex and we become aware of them (e.g. touch, pain, hearing etc) •The process of sensation begins in a sensory receptor which can be either a specialised cell or the dendrites of a sensory neuron The following must take place for sensation to occur: •A stimulus must occur within the receptive field of the receptor (receptive field is the pickup area of a particular neuron). •The sensory receptor transduces energy in a stimulus (e.g. mechanical, thermal, chemical) into a graded/receptor potential (electrochemical energy). Note that each type of sensory receptor can only transduce one kind of stimulus; selectivity •If graded potential reaches threshold, an action potential is triggered which propagates to CNS via 1st order neurons (the 1st order neuron is always associated with the receptor/stimulus) •Integration of sensory input takes place in a particular region of the CNS via 2nd & 3rd order neurons with conscious sensation perceived in cerebral cortex only. Note that most sensory input is filtered out at brainstem level

General Classes of Neurons

Sensory (afferent) neurons Interneurons (association neurons) Motor (efferent) neurons

type a

Sensory information from skeletal muscles travels over ________ fibers.

What are the three functional classifications of neurons?

Sensory neurons (AKA afferent neurons) Motor neurons (AKA efferent neurons) Interneurons (AKA associations neurons)

Muscle that requires voluntary stimulation for activation

Skeletal

Running a marathon

Slow oxidative muscle fibers

Soma

Somas range from 5 to 135 μm in diameter, and axons from 1 to 20 μm in diameter and from a few millimeters to more than a meter long.

False

Somatic reflexes are responses of skeletal, smooth and cardiac muscles.

the viscera.

Somatosensory refers to these sensory signals except the sensory signals from

pyramids

Some of the white matter forms bulges on the anterior aspect of the medulla. - These protrusions are formed by the large corticospinal tracts that pass from the cerebrum to the spinal cord

What are the two subdivisions within the ANS?

Sympathetic and parasympathetic

Cholinergic synapses

Synapses that release ACh

Small space between the sending neuron and the receiving neuron is

Synaptic cleft

What is the space that separates the two cells in a synapse?

Synaptic cleft

What is at the end of telodendria?

Synaptic terminals

Describe the receptors for taste and explain how they are stimulated

Taste receptors: Gustation - sensation of taste Results from action of chemicals (tastants) on taste buds Taste buds are banana shaped epithelial cells that: •have tufts of microvilli called taste hairs which project into a pit called a taste pore •Lie between supporting cells •Have synaptic vesicles at base of cell which release neurotransmitter when stimulated by a tastant •Liberated neurotransmitter molecules trigger nerve impulses in the 1st order sensory neurons that synapse with the base of the gustatory receptor cells •Taste buds are located mainly on tongue in protrusions called papillae (foliate, fungiform, vallate&filiform). Basal cells are stem cells that multiply and replace dead taste cells. Supporting cells have no sensory role on synaptic vesicles.

Auditory Area

Temporal Lobe

The primary auditory cortex is located in the ____

Temporal Lobe

proprioceptors.

Tendon organs are

Sympathetic Division

Tends to arouse the body for action—for example, by accelerating the heartbeat and increasing respiratory airflow—but it inhibits digestion.

Parasympathetic Division

Tends to have a calming effect—slowing the heartbeat, for example—but it stimulates digestion.

In a multipolar neuron what does the axon end with?

Terminal branches called telodendria

Part of CNS that sorts all of ascending sensory information

Thalamus

1. Which part of the CNS sorts almost all of the ascending sensory information?

Thalamus. Afferent impulses from all senses and all parts of the body converge on the thalamus and synapse with at least one of its nuclei. The thalamus-- which sorts out and edits these afferent signals before relaying them to the appropriate cortical areas--is considered the gateway to the cerebral cortex. In summary, the thalamus plays a key role in mediating sensation, motor activities, cortical arousal, learning, and memory.

cranial nerves

The 12 pairs of cranial nerves are so-named because they pass through various foramina in the bones of the cranium. - Like the 31 pairs of spinal nerves, they are part of the peripheral nervous system (PNS). Each cranial nerve has both a number, designated by a roman numeral, and a name (see Figure 14.5). The numbers indicate the order, from anterior to posterior, in which the nerves arise from the brain. The names designate a nerve's distribution or function.

What is the primary function of Na+/K+ pumps in maintaining the RMB?

The Na+/K+ pumps don't do much in the way of establishing the RMP but are very important in maintaining it by pumping out more Na+ than in K+ at a ratio of 3 Na+ : 2 K

Describe how the resting membrane potential is established and maintained in neurons.

The RMP is a result of plasma membrane permeability to ions, particularly those established by K+ and Na+ leak channels and then maintained byt Na+/K+ membrane pumps.

Temporal summation

The addition of stimuli occurring in rapid succession at a single synapse that is actively repeated

all stimuli great enough to bring the membrane to threshold will produce identical action potentials

The all-or-none principle states that a. only sensory stimuli can activate action potentials. b. the greater the magnitude of the stimuli, the greater the magnitude of the action potential. c. only motor stimuli can activate action potentials. d. all stimuli will produce identical action potentials. e. all stimuli great enough to bring the membrane to threshold will produce identical action potentials.

What is the Base of the Crus Cerebri of the cerebral peduncle composed of?

The base of the Crus Cerebri of the cerebral peduncle is composed of C.S. and C.B. fibers

Neurons

The basic functional unit of the nervous system

Maintaining Internal Coordination

The endocrine system: communicates by means of chemical messengers (hormones) secreted into the blood. Nervous system: which employs electrical and chemical means to send messages very quickly from cell to cell.

A nurse is asked about the cause of the excruciating pain of tic douloureux. How should the nurse answer?

The excruciating pain is caused by inflammation of the trigeminal nerve. Pressure on the trigeminal nerve root can turn normal stimuli, like tooth brushing, into painful stimuli.

What are the three important concepts regarding the transmembrane potential?

The extracellular fluid and intracellular fluid differ greatly in ionic composition Cells have selectively permeable membranes Membrane permeability varies by ion

alpha motor neurons.

The fibers that carry action potentials to cause skeletal muscle to contract are

parallel after-discharge circuit

The flexor (withdrawal) reflex employs a ____, which maintains a sustained contraction.

to protect neurons in both the ascending and descending tract.

The following are all functions associated with the spinal cord except

delta waves

The frequency of these waves is 1-5 Hz. Delta waves occur during deep sleep in adults, but they are normal in awake infants. When produced by an awake adult, they indicate brain damage.

beta waves

The frequency of these waves is between 14 and 30 Hz. Beta waves generally appear when the nervous system is active—that is, during periods of sensory input and mental activity.

Does the generation of IPSPs make it more likely or less likely that a nerve signal will be sent?

The generation if IPSPs produced by loss of K+ or gain of Cl- make it less likely that a nerve signal will be sent because the membrane potential has moved away from the threshold (value that must be reached for a nerve signal to be initiated)

Which of the following generalizations does not describe the cerebral cortex? Each hemisphere is chiefly concerned with sensory and motor functions of the contralateral side of the body. The hemispheres are exactly equal in function. The cerebral cortex contains three kinds of functional areas. No functional area of the cortex works alone.

The hemispheres are exactly equal in function. (not true)

Choose the FALSE statement about nerves.

The majority of a nerve's bulk is due to axons.

a

The mechanism by which the neurotransmitter is returned to a presynaptic neuron's axon terminal is specific for each neurotransmitter. Which of the following neurotransmitters is broken down by an enzyme before being returned? a. acetylcholine b. glutamate

cardiovascular center

The medulla also contains several nuclei, masses of gray matter where neurons form synapses with one another. Several of these nuclei control vital body functions. - The cardiovascular center regulates the rate and force of the heartbeat and the diameter of blood vessels.

Which protective covering of the brain provides passageways for cerebrospinal fluid (CSF) to drain into the superior sagittal sinus? arachnoid mater membranous part of the dura mater periosteal part of the dura mater pia mater

The membranous part of the dura mater, called the meningeal layer, forms the true external covering of the brain and continues caudally in the vertebral canal as the spinal dura mater. The meningeal layer does not provide passageways for CSF to leave the subarachnoid space and enter the venous blood of the sinus. The subarachnoid space is filled with CSF. Knoblike projections of the arachnoid mater, called arachnoid villi, protrude superiorly through the dura mater and into the superior sagittal sinus. These villi provide a passageway for CSF to leave the subarachnoid space and enter the venous blood of the sinus.

threshold

The minimum stimulus required to trigger an action potential is known as the a. threshold. b. incentive. c. all-or-none response. d. summation. e. potential.

Local current

The movement of positive charges parallel to the inner and outer surfaces of a membrane

sodium

The movement of what ion is responsible for the local currents that depolarize other regions of the axon to threshold? a. voltage-gated sodium (Na+) channels b. calcium (Ca2+) c. Potassium (K+) d. sodium (Na+)

neurotransmitter and receptor

The same ________ can have different effects depending on the properties of the ________.

gamma motor neurons.

The sensitivity of the muscle spindle is maintained by

How do the primary functional divisions of the nervous system differ?

The sensory (afferent) system brings information from somatic (conscious stimuli) and visceral (unconsciously perceived stimuli) from receptors all throughout the body and sends it to the CNS. The motor (efferent) system initiates and transmits the response from the CNS to somatic (voluntary) effectors and autonomic (non voluntary) effectors to illicit a response from muscle tissue and glands.

demyelination

The sensory loss and muscle weakness associated with multiple sclerosis are a consequence of a. excessive myelin layers around the axonal fibers. b. a neuron not having a myelin sheath. c. too few nodes of Ranvier. d. demyelination. e. a neuron without a neurilemma.

What are the two primary functional divisions of the nervous system?

The sensory nervous system (afferent) receives sensory information from receptors and transmits it to the CNS. Somatic & visceral sensory components detect different types of stimuli. The motor nervous system (efferent) initiates and transmits motor output from the CNS to effectors and controls muscle tissues and glands. Somatic and autonomic components exert voluntary or autonomic control.

Conduction Speed of Nerve Fibers

The speed at which a nerve signal travels along a nerve fiber depends on two factors: the diameter of the fiber and the presence or absence of myelin. Signal conduction occurs along the surface of a fiber, not deep within its axoplasm. Large fibers have more surface area and conduct signals more rapidly than small fibers. Myelin further speeds signal conduction for reasons discussed later. Nerve signals travel about 0.5 to 2.0 m/s in small unmyelinated fibers (2-4 μm in diameter) and 3 to 15 m/s in myelinated fibers of the same size. In large myelinated fibers (up to 20 μm in diameter), they travel as fast as 120 m/s. One might wonder why all of our nerve fibers are not large, myelinated, and fast, but if this were so, our nervous system would be impossibly bulky or limited to far fewer fibers. Large nerve fibers require large somas and a large expenditure of energy to maintain them. The evolution of myelin allowed for the subsequent evolution of more complex and responsive nervous systems with smaller, more energy-efficient neurons. Slow unmyelinated fibers are quite sufficient for processes in which quick responses are not particularly important, such as secreting stomach acid or dilating the pupil. Fast myelinated fibers are employed where speed is more important, as in motor commands to the skeletal muscles and sensory signals for vision and balance.

pelvic.

The spinal cord is divided into all of the following regions except

Which of the following is an incorrect statement regarding the occurrence of a sensation?

The stimulus energy must be converted into the energy of a graded potential called a transduction potential.

Which of the following is an incorrect statement regarding the occurrence of a sensation? Choose one answer. a. The stimulus energy must occur within the receptor's receptive field b. The stimulus energy must be converted into the energy of a graded potential called a transduction potential. c. The stimulus energy must match the specificity of the receptor. d. A generator potential in the associated sensory neuron must reach threshold.

The stimulus energy must be converted into the energy of a graded potential called a transduction potential.

False

The stretch reflex is a tendency of a muscle to stretch when it is overcontracted.

Which of the following hypothalamic control centers would you predict is the LEAST important for survival? suprachiasmatic nucleus autonomic control center temperature control center thirst center

The superchiasmatic nucleus. This area of the hypothalamus is important in determining the circadian rhythm that sets our sleep-wake cycles. It is our biological clock.

cerebellar cortex

The superficial layer of the cerebellum - consists of gray matter in a series of slender, parallel ridges called folia

prevents overcontraction of a muscle.

The tendon reflex

False

The tendon reflex is the inhibition of a muscle contraction that occurs when its tendon is excessively stretched.

31

There are __ pairs of spinal nerves.

Explain the functional organization of the nervous system.

There are two functional divisions; the sensory nervous system and the motor nervous system. Both sensory and motor have both CNS and PNS components.

How are active channels/gated channels opened?

They open and close in response to specific stimuli

reflexes are spontaneous actions of the nervous system.

These are all properties of reflexes except

alpha waves

These rhythmic waves occur at a frequency of about 8-13 cycles per second. (The unit commonly used to express frequency is the hertz [Hz]. One hertz is one cycle per second.) Alpha waves are present in the EEGs of nearly all normal individuals when they are awake and resting with their eyes closed. These waves disappear entirely during sleep.

theta waves

These waves have frequencies of 4-7 Hz. Theta waves normally occur in children and adults experiencing emotional stress. They also occur in many disorders of the brain.

Internuclear Opthalmoplegia Damaged Conditions:

To the MLF between CN3 and CN6 results in intranuclear opthalmoplegia where the lateral rectus contracts normally during horizontal eye movements but the medial rectus of the eye ipsilateral to the lesion does not contract (e.g. damage to the left MLF , cannot adduct left eye whe looking to right)

Pneumotaxic area and apneustic area

Together with the medullary rhythmicity area, they help control breathing.

Representative of receptor level processing, not perceptual level processing

Transduction (converting stimulus into neural signal)

Cranial Nerve V

Trigeminal Nerve Major function: Carry nerve impulses associated with head sensations and chewing muscles

Cranial Nerve IV

Trochlear nerve Major function: Control some of the muscles moving the eyeballs

26. The brain and spinal cord begin as an embryonic structure called the neural plate.

True

identify factors that influence regeneration of PNS axons, and explain why axon regeneration in the CNS is limited.

Two factors involve axon regeneration in the PNS. The distance between the site of damage and the amount of damage. Potential regeneration of damaged neurons within the CNS is limited because oligodendrocytes do not release a nerve growth factor, the large number of axons crowded within the CNS tends to complicate regrowth and both astrocytes and connective tissue coverings may form some scar tissue that obstructs axon regrowth.

What are the three groups of axons and briefly describe each

Type A fibers - The largest myelinated axons (action potential speeds of up to 268 mph) Type B fibers - Smaller myelinated axons (action potential speeds of up to 40 mph) Type C fibers - Unmyelinated axons (action potential speeds of up to 2 mph)

A

Type ________ fibers have the largest diameter axons.

Retrograde Transport

Uses a motor protein called dynein

What cranial nerve innervated most of visceral organs

Vagus

Cranial Nerve X

Vagus Nerve Major function: Carry nerve impulses to and from many organs in the thoracic and abdominal cavities

the areas that have had the action potential are refractory to a new action potential

Why does the action potential only move away from the cell body? a. The flow of the sodium ions only goes in one direction—away from the cell body b. The areas that have had the action potential are refractory to a new action potential.

Descending tracts

___ carry motor commands from the brain along the spinal cord

Special

___ fibers innervate eyes and ears.

Endoneurium

___ keep(s) nerve fibers insulated from one another.

Which of the following cranial nerves carries only motor information? a) abducens b) optic c) trigeminal d) olfactory

a) abducens

Which of the following is an excitatory neurotransmitter secreted by motor neurons innervating skeletal muscle? a) acetylcholine b) norepinephrine c) gamma aminobutyric acid d)bcholinesterase

a) acetylcholine

The term central nervous system refers to the ________. a) brain and spinal cord b) brain, spinal cord, and peripheral nerves c) spinal cord and spinal nerves d) autonomic nervous system

a) brain and spinal cord

Pressure, pain, and temperature receptors in the skin are ________. a) exteroceptors b) mechanoreceptors c) proprioceptors d) interoceptors

a) exteroceptors

Which type of sensory receptor allows us to feel an insect landing on our skin? a) mechanoreceptor b) nociceptor c) chemoreceptor d) thermoreceptor

a) mechanoreceptor

Which of the following types of neurons carries impulses away from the CNS? a) motor b) association c) afferent d) sensory

a) motor

The substance released at axon terminals to propagate a nervous impulse is called a(n) ________. a) neurotransmitter b) cholinesterase c) ion d) biogenic amine

a) neurotransmitter

For our motor commands to travel toward our muscles, the signals must travel on __________. a) projection fibers b) association fibers c) the primary visual cortex d) commissural fibers

a) projection fibers

Which of the following is the correct simple spinal reflex arc? a) receptor, afferent neuron, integration center, efferent neuron, effector b) receptor, efferent neuron, integration center, afferent neuron, effector c) effector, efferent neuron, integration center, afferent neuron, receptor d) effector, afferent neuron, integration center, efferent neuron, receptor

a) receptor, afferent neuron, integration center, efferent neuron, effector

Segmental refers to which level of motor control? a) spinal cord b) basal nuclei c) cerebellum d) brain stem

a) spinal cord

Which of the following is NOT a diencephalon component? a) superior colliculus b) pineal gland c) thalamus d) hypothalamus

a) superior colliculus

An impulse from one nerve cell is communicated to another nerve cell via the ________. a) synapse b) effector c) receptor d) cell body

a) synapse

Which part of the CNS sorts almost all of the ascending sensory information? a) thalamus b) hypothalamus c) mesencephalon d) pons

a) thalamus

Which of the following characteristics is representative of receptor-level processing, NOT perceptual-level processing? a) transduction b) spatial discrimination c) detection d) magnitude

a) transduction

Wernicke's area

aka posterior language area a broad region in the left temporal and parietal lobes, interprets the meaning of speech by recognizing spoken words. - It is active as you translate words into thoughts. The regions in the right hemisphere that correspond to Broca's and Wernicke's areas in the left hemisphere also contribute to verbal communication by adding emotional content, such as anger or joy, to spoken words.

What are 2 ways the spinal cord promotes homeostasis?

allows nerve impulse to move from brain to motor areas, and synapse occurs in white matter

accessory

allows you to shrug your shoulders

rabies herpes

also enter the axon and go the cell body and CNS

leakage nongated channel

always open allow K+ to leak out of the cell for action potential to occur

The goal of information processing during a neural reflex is the selection

an appropriate motor response and the activation of specific motor neurons

What is another name for the basal nuclei?

basal ganglia

Why is the crossed extensor reflex an example of a contralateral reflex arc?

because response is occuring on the opposite of the body

an epidural block

can be given to control pain during labor

Cerebral Aquaduct

canal like; runs through the midbrain; connects 3rd and 4th ventricles

insula

cannot be seen at the surface of the brain because it lies within the lateral cerebral sulcus, deep to the parietal, frontal, and temporal lobes

facial

cant smile, wrinkle foehead, secrete tears, or close eyes (on the affected side)

true

capillaries in the brain are unique from other capillaries as they have more tight junctions and limit endocytosis and exocytosis. true or false?

sensory

carries information for touch, pressure, and pain

sensory

carries information to the parietal lobe

Efferent division

carries motor commands to muscles, glands, and organs

Afferent division

carries sensory information from sensory receptors to CNS

What is least descriptive of the oculomotor nerve?

carries sensory information from the eye to the occipital lobe (vision)

optic

carries sensory information from the eyes to the occipital lobe of the brain

Spinal Cord

central cavity surrounded by gray matter (mostly neuron cell bodies); external white matter composed of myelinated fiber tracts

What parts of the brain ultimately plan and coordinate complex motor activities?

cerebellum and basal nuclei

What is the name of the canal connecting the third and fourth ventricles?

cerebral aqueduct

Adult Brain Regions

cerebral hemispheres, diencephalon, brain stem, and cerebellum

The space between the arachnoid and pia mater is filled with

cerebrospinal fluid

The ________ nerve is not a branch of the trigeminal nerve.

cervical

The primary nerve that controls breathing is found in which nerve plexus?

cervical

the trapezius muscle is innervated by nerves from which plexus?

cervical

Irritation of a major nerve of this plexus may cause hiccups. Choose one answer. a. thoracic plexus b. sacral plexus c. cervical plexus d. lumbar plexus

cervical plexus

What is the difference between the conus medullaris and the cauda equina?

conus medullaris is the name of the end of the spinal cord; the spinal cord does not reach the end of the vertebral column; growing down to the end of the vertebral column is a collection of nerve roots that resembles a horse's tail; this collection of fibers is called the cauda equina. The collection of nerve roots at the inferior end of the vertebral canal is named the cauda (tail) equina (horse) because it resembles a horse's tail. This strange arrangement reflects the fact that during fetal development, the vertebral column grows faster than the spinal cord, forcing the lower spinal nerve roots to "chase" their exit points inferiorly through the vertebral canal.

several neurons synapsing on a single postsynaptic neuron are

convergence

motor

corticospinal tract

What is another name for pyramidal tracts?

corticospinal tracts

epineurium

covering of the entire nerve

optic

cranial nerve II

vestibulocochlear

cranial nerve VIII

vagus

cranial nerve X

The __________ reflex involves activating muscles contralateral to the receptor. flexor tendon stretch crossed extensor

crossed extensor

respiratory arrest

damage above C3 causes

Damage to which visual area of the brain can result in blindness?

damage to the primary visual cortex results in blindness

optic

damage to this nerve causes blindness

pudendal

deadening of this nerve assists in childbirth

association areas

deal with more complex integrative functions such as memory, emotions, reasoning, will, judgment, personality traits, and intelligence. - consist of some motor and sensory areas, plus large areas on the lateral surfaces of the occipital, parietal, and temporal lobes and on the frontal lobes anterior to the motor areas. - Association areas are connected with one another by association tracts

Fissures

deeper grooves which seperate large regions of the brain

Patients who have lesions involving Broca's area __________.

do not understand language *can understand language, but have difficulty speaking do not understand written communications, but they can speak clearly and intelligibly can communicate through writing or sign language, but they cannot speak Patients with lesions involving Broca's area can understand language but have difficulty speaking (and sometimes cannot write or type or use sign language) - this disorder is called expressive, or Broca's, aphasia. On the other hand, patients with lesions involving Wernicke's area are able to speak but produce a type of nonsense often referred to as "word salad" - this disorder is called receptive, or Wernicke's, aphasia. These patients also have great difficulty understanding language.

What are the roots of the spinal nerve? Describe the structure and function of each of the roots.

dorsal and ventral roots; dorsal root has ganglia

The tough, fibrous, outermost covering of the spinal cord is the periosteum. pia mater. epidural block. arachnoid. dura mater.

dura mater.

CSF

in between the dura mater and arachnoid mater

the highest level of motor control involves a series of interactions that occur

in centers in the brain that can modulate or build on reflexive motor patterns

Anterior Association Area

in frontal lobe, also called prefrontal cortex; the most complicated cortical region of all; involved with intellect, complex learning abilities, recall, and personality; contains working memory needed for judgment, reasoning, persistence, and conscience; development depends on feedback from social enviornment

frontal eye field area

in the frontal cortex; is sometimes included in the premotor area -controls voluntary scanning movements of the eyes—like those you just used in reading this sentence.

d

in the spinal cord, nerve tracts or funiculi make up the _______. a. central canal b. gray horns c. gray commissure d. white columns

no plexus

in thoracic region

If "wrist drop" were to appear, there would also be an increased probability of ______.

inability to extend the forearm

cervical plexus

include head, neck and shoulders

brachial plexus

include nerves from C5-T1 supplies the shoulder and arm

sacral plexus

includes L4-S3 posterior thigh and area below the knee

Limbic Association Area

includes cingulate gyrus, the parahippocampal gyrus, and hippocampus; part of limbic system; provides emotional impact that makes a scene important to us; hippocampus establishes memories that allow us to remember incidents

Distinguish between an ipsilateral reflex and a contralateral reflex.

ipsilateral reflex-response happens on the same side of the stimulus, contralateral reflex-response happens on the oppiste side of the body

Slow Axonal Transport

is an anterograde process that works in a stop-and-go fashion. If we compare fast axonal transport to an express train traveling nonstop to its destination, slow axonal transport is like a local train that stops at every station. When moving, it goes just as fast as the express train, but the frequent stops result in an overall progress of only 0.5 to 10 mm/day. It moves enzymes and cytoskeletal components down the axon, renews worn-out axoplasmic components in mature neurons, and supplies new axoplasm for developing or regenerating neurons. Damaged nerve fibers regenerate at a speed governed by slow axonal transport.

Regeneration within the CNS ________.

is prevented due to growth-inhibiting proteins of oligodendrocytes

motor nuclei

issue motor commands to peripheral effectors

Cerebral Cortex

it enables us to be aware of ourselves and our sensations, to communicate, remember, and understand, and to initiate voluntary movements; composed of gray matter: neuron cells bodies, dendrites, associated glia and blood vessels; thin (2-4mm); 40% of the mass of the brain; each hemisphere connects to contralateral side of body; two hemispheres not entirely equal in functions

somatosensory association area

just posterior to and receives input from the primary somatosensory area, as well as from the thalamus and other parts of the brain - This area permits you to determine the exact shape and texture of an object without looking at it, to determine the orientation of one object with respect to another as they are felt, and to sense the relationship of one body part to another. - Another role of the somatosensory association area is the storage of memories of past sensory experiences, enabling you to compare current sensations with previous experiences. For example, the somatosensory association area allows you to recognize objects such as a pencil and a paperclip simply by touching them.

phrenic nerve c3-c5

keep diaphragm alive

The white matter of the spinal cord contains

large numbers of myelinated and unmyelinated axons

Posterior Association Area

large region encompassing parts of temporal, parietal, and occipital lobes; play role in recognizing patterns and faces, localizing us and our surroundings in space, and binding different sensory inputs into a coherent whole; involved in understanding written and spoken language

hemispheric lateralization - physiology

left hemisphere receives somatic sensory signals from and controls muscles on the right side of the body, whereas the right hemisphere receives sensory signals from and controls the left side of the body. In most people the left hemisphere is more important for reasoning, numerical and scientific skills, spoken and written language, and the ability to use and understand sign language. Conversely, the right hemisphere is more specialized for musical and artistic awareness; spatial and pattern perception; recognition of faces and emotional content of language; discrimination of different smells; and generating mental images of sight, sound, touch, taste, and smell to compare relationships among them.

Brocas's Area

lies anterior to the inferior region of the premotor area; present in one hemisphere only (usually the left); a motor speech area that directs muscles of the tounge; is active as one prepares to speak

fourth ventricle

lies between the brain stem and the cerebellum.

pons

lies directly superior to the medulla and anterior to the cerebellum and is about 2.5 cm (1 in.) long - consists of both nuclei and tracts - bridge that connects parts of the brain with one another; relays impulses from one side of the cerebellum to the other and between the medulla and midbrain. - These connections are provided by bundles of axons. Some axons of the pons connect the right and left sides of the cerebellum. Others are part of ascending sensory tracts and descending motor tracts. - some nuclei in the pons are the pneumotaxic area and the apneustic area - also contains nuclei associated with the following four pairs of cranial nerves: trigeminal (V) nerves, abducens (VI) nerves, facial (VII) nerves, and vestibulocochlear (VIII) nerves.

Central Sulcus

lies in the frontal plane, and seperates frontal lobe from parietal lobe

Olfactory Cortex

lies on medial aspect of the temporal lobe in a small region called piriform lobe which is dominated by hooklike uncus; part of the primitive rhinecephalon which includes all parts of cerebrum that recieves olfactory signals (olfactory tracts and bulbs that extend to the nose); region of conscious awarness of oders

Somatosensory Association Cortex

lies posterior to primary somatosensory cortex and has many connections with it; function is to integrate sensory inputs (temperature, pressure, and so forth) relayed to it via the primary somatosensory cortex to produce an understanding of an object being felt; determines size, texture, and relationships of parts of objects being felt

myelin

lipid protein produced by schwann cells

primary gustatory area

located at the base of the postcentral gyrus superior to the lateral cerebral sulcus in the parietal cortex - receives impulses for taste and is involved in gustatory perception.

primary somatosensory area

located directly posterior to the central sulcus of each cerebral hemisphere in the postcentral gyrus of each parietal lobe. - extends from the lateral cerebral sulcus, along the lateral surface of the parietal lobe to the longitudinal fissure, and then along the medial surface of the parietal lobe within the longitudinal fissure. - receives nerve impulses for touch, proprioception (joint and muscle position), pain, itching, tickle, and temperature and is involved in the perception of these sensations. - A "map" of the entire body is present in the primary somatosensory area: Each point within the area receives impulses from a specific part of the body - the size of the cortical area receiving impulses from a particular part of the body depends on the number of receptors present there rather than on the size of the body part. - The primary somatosensory area allows you to pinpoint where sensations originate, so that you know exactly where on your body to swat that mosquito.

Primary Auditory Cortex

located in superior margin of temporal lobe abutting the lateral sulcus; interprets information from inner ear as pitch, loudness, and location

visual association area

located in the occipital lobe - receives sensory impulses from the primary visual area and the thalamus. - It relates present and past visual experiences and is essential for recognizing and evaluating what is seen. For example, the visual association area allows you to recognize an object such as a spoon simply by looking at it.

primary motor area

located in the precentral gyrus of the frontal lobe - Each region in the primary motor area controls voluntary contractions of specific muscles or groups of muscles - Electrical stimulation of any point in the primary motor area causes contraction of specific skeletal muscle fibers on the opposite side of the body - As is true for the primary somatosensory area, body parts do not "map" to the primary motor area in proportion to their size. More cortical area is devoted to those muscles involved in skilled, complex, or delicate movement. For instance, the cortical region devoted to muscles that move the fingers is much larger than the region for muscles that move the toes.

primary auditory area

located in the superior part of the temporal lobe near the lateral cerebral sulcus - receives information for sound and is involved in auditory perception.

primary olfactory area

located in the temporal lobe on the medial aspect - receives impulses for smell and is involved in olfactory perception.

auditory association area

located inferior and posterior to the primary auditory area in the temporal cortex - allows you to recognize a particular sound as speech, music, or noise.

Parietooccipital Sulcus

located on the medial surface of the hemisphere

Frontal Eye Field

located partially in and anterior to the permotor cortex and superior to Broca's area; controls voluntary movement of the eyes; wont control eye reflexes

Auditory Association Area

located posterior to primary auditory cortex; permits perception of the sound stimulus; stores memories of sounds and permits perception of sounds

the epidural space is an area that contains

loose connective tisue, blood vessels, and adipose tissue

Injury to the hypothalamus may result in all of the following except ________. pathologic sleep loss of body temperature control production of excessive quantities of urine loss of proprioception

loss of proprioception

What is a consequence of damage to the glossopharyngeal nerve?

loss of the gag reflex and aspiration fo food

Pyramidal Tracts

massive voluntary motor tracts formed by long axons of pyramidal cells whichh project to the spinal cord

The white matter of the spinal cord is mainly neuroglia. Schwann cells. unmyelinated axons. myelinated and unmyelinated axons. nodes of Ranvier.

myelinated and unmyelinated axons.

A distinction about the flexor reflex is that it __________. prevents a muscle from overstretching is an example of a monosynaptic reflex moves a limb away from a painful stimulus prevents a muscle from generating excessive tension

moves a limb away from a painful stimulus

Fast Anterograde Transport

moves mitochondria; synaptic vesicles; other organelles; components of the axolemma; calcium ions; enzymes such as acetylcholinesterase; and small molecules such as glucose, amino acids, and nucleotides toward the distal end of the axon.

Which of the following is composed of encapsulated nerve endings?

muscle spindles

the sensory receptors in the stretch reflex are the

muscle spindles

muscle spasm

muscles contract completely with no relaxation

The flexor muscles in the anterior arm (biceps brachii and brachialis) are innervated by what nerve?

musculocutaneous

The flexor muscles in the anterior arm (biceps brachii and brachialis) are innervated by what nerve? Choose one answer. a. ulnar b. radial c. median d. musculocutaneous

musculocutaneous

sciatic

must administer an intramuscular (IM) injection in the upper outer quadrant of the buttocks to avoid jumping this nerve

ion insulator

myelin acts as an

oligdendrocytes

myelinate axons in the CNS

plexus(es)

nerve groupings that are described as cervical, brachial, and lumbosarcral nerves

oculomotor

nerve that supplies most of the extrinsic eye muscles, primary function is the movement of the eyeballs

phrenic

nerve that supplies the diaphragm, an important breathing muscle

cauda equine

nerves

cervical enlargement

nerves come out to serve arms

lumbar enlargement

nerves come out to serve legs

Compounds that influence the postsynaptic cells' response to a neurotransmitter are called...

neuromodulators

refractory period

neuron can not generate another action potential

Feeling a gentle caress on your arm would likely involve all of the following except ________.

pacinian corpuscles

Lateral Ventricles

paired; one deep within each cerebral hemisphere; large C-shaped chambers that reflect the pattern of cerebral growth; each ventricle communicates with third ventricle

8

pairs of cervical nerves

Which part of the brain stem houses the reflex centers for respiration and cardiovascular functioning?

the medulla oblongata The medulla contains many important functional groups of visceral motor nuclei, including the cardiovascular (CV) and respiratory centers. The CV center includes the cardiac center, which adjusts the force and rate of heart contraction to meet the body's needs, and the vasomotor center, which changes blood vessel diameter to regulate blood pressure. The respiratory centers generate the respiratory rhythm and (in concert with pontine centers) control the rate and depth of breathing. The olivary nuclei and cough, sneezing, swallowing, and vomiting centers are also in the medulla.

Meninges

the meninges cover the entire spinal cord and extend over the spinal nerve roots to fuse with tissue covering the spinal nerves

longitudinal fissure

the most prominent fissure in the brain - divides the brain into L and R hemispheres.

Name the three regions of the cerebral hemispheres. What type of brain tissue is found in each one?

the most superficial region is the cortex; it consists of gray matter; deep to the cortex is internal white matter; and the third the basal ganglia, which are small islands of gray matter located deep within the white matter

Axoplasmic transport

the movement of materials between the cell body and synaptic terminals

d

the neurotransmitter orexin plays a role in _______. a. the regulation of metabolism b. the promotion of sleepiness c. body temperature regulation d. the promotion of wakefulness

Which of the following is NOT used to classify sensory receptors?

the number of dendritic endings present

__________ do NOT exhibit the property of adaptation.

tonic receptors

dura matter

tough mother outer singular

arbor vitae

tracts of white matter deep to the grey matter of the cerebellar cortex

A knee-jerk reflex that is unusually strong may be caused by ______.

transmission of excitatory signals from the brain to the neurons that form the femoral nerve

nerve impulse

traveling action potential

The cranial nerves that have neural connections with the tongue include all except the ________.

trochlear

External strabismus and ptosis could be caused by damage to the oculomotor nerve.

true

The only cranial nerves to extend beyond the head and neck region are the vagus nerves.

true

poliomyelitis

viral infection causing motor neuron death in the spinal cord possible death from heart failure or respiratory arrest

in the spinal cord, the gray horns contain__

visceral and somatic sensory and motor nuclei

Which of the following is not an aspect of sensory perception?

visceral identification

28. The area of the cortex that is responsible for sensing a full bladder and the feeling that your lungs will burst when you hold your breath too long is the

visceral sensory area

An individual who could trace a picture of a bicycle with his or her finger but could not recognize it as a bicycle is most likely to have sustained damage to the ________. Choose one answer. a. visual association area b. calcarine cortex c. lateral geniculate body d. primary visual area

visual association area

somatic NS

voluntary

c

what are the three primary brain vesicles that form from the neural tube? a. mesencephalon, telencephalon, diencephalon b. brainstem, diencephalon, cerebellum c. forebrain, midbrain, hindbrain d. midbrain, pons, medulla oblongata

b

what connects the upper motor neurons to lower motor neurons? a. sensory neurons b. interneurons c. muscle fibers d. primary afferent neuron

Describe the projection pathways for smell

•Sensory neurons project via the olfactory nerves to synapse with mitral cells in olfactory glomeruli (spherical structures that receive input from one type of olfactory receptor) in the olfactory bulb. •These mitral cells (second order neurons) in the olfactory bulb project via the olfactory tract to the olfactory cortex (enterhinal cortex) in the medial temporal lobe directly, or via another pathway through the thalamus to orbitofrontal cortex. •From olfactory cortex signals travel to insula, frontal cortex, hippocampus, amygdala and hypothalamus. •Input to these areas can evoke memories, emotions and visceral reactions.


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