A&P Test3
the nerve contained both sensory and motor neurons
Carpal tunnel results in damage to one medial nerve that resultless in lack of control to the wrist and also numbness. This indicates that
reverberating (oscillating) circuits
Characterized by feedback by axon collaterals to previous points in the pathway, resulting in ongoing stimulation of the pathway.
converging circuits
Characterized by reception of input from many sources, and a funneling to a given circuit, resulting in strong stimulation or inhibition.
b. nondecremental
At the distal end of a nerve fiber, action potentials have the same voltage as they had at the beginning. That is to say they are a. saltatory b. nondecremental c. refractory d. irreversible e. self-propagating
Nondecrimential
At the distal end of a nerve fiber, action potentials have the same voltage as they had at the beginning. That is to say, they are
in the retina of the eye
Bipolar neurons are commonly found
astrocytes
Blood capillaries of the brain are enveloped by
resting membrane potential
Degree of difference in electrical charge inside and outside a neuron.
true
Dendrites do not release neurotransmitters
epineurium
Fibrous sheath inclosing a nerve.
oran of corti
In the inner ear, the transducer that converts vibrations caused by sound to nerve impulses is the ___.
Long and myelinated and the postganglionic neuron is short and nonmyelinated
In the parasympathetic division, the preganglionic neuron is
contract and the antagonist muscle, the hamstrings, to relax
In the patellar tendon reflex arc, the patellar ligament is stretched, which stretches the quadriceps femoris muscle. This reflex will cause the quadricepts femoris to
nodes of ranvier
In the peripheral nervous system, myelin sheaths have gaps called _____ about 1mm apart
stimulate the intrafusal fibers to contract
In the skeletal muscle, the flower-spray endings' function is to
Short and myelinated and the postganglionic neuron is long and nonmyelinated
In the sympathetic division, the preganglionic neuron is
relatively refractory period
In this period, an exceptionally strong stimulus can trigger a response.
repolarization
In this period, potassium ions diffuse out of the neuron due to a change in membrane permeability.
depolarization
In this period, the interior of the cell becomes less negative due to an influx of sodium ions.
from air to the cornea
In vision, most light refraction occurs at the interface where light passes ___.
Degradation by enzymes from the postsynaptic cell or within the synaptic cleft; reuptake by astrocytes or the presynaptic cell; or diffusion away from the synapse.
In what three ways are neurotransmitter effects terminated?
histamine
Increases acid secretion in the stomach; blocked by cimetidine.
cerebral cortex
Location of the conscious mind, allowing us to communicate, remember, and understand.
d. substance p
Long term memories occur when there are more of these receptors a. NMDA b. dopamine c. acetylcholine d. substance p e. nicotine
FALSE
T/F: Strong stimuli cause the amplitude of action potentials generated to increase.
FALSE
T/F: The all-or-none phenomenon is applied to nerve conduction states that the whole nerve cell must be stimulated for conduction to take place.
FALSE
T/F: The nodes of Ranvier are found only on myelinated, peripheral neuron processes.
TRUE
T/F: The oligodendrocytes can myelinate several axons.
TRUE
T/F: Unipolar neurons have axons structurally divided into peripheral and central processes.
a. olfactory nerve
The ___ is a purely sensory nerve a. olfactory nerve b. trigeminal nerve c. facial nerve d. vestibulocochlear nerve e. glossopharyngeal nerve
olfactory nerve
The ___ is a purely sensory nerve.
malleus
The ___ is attached to the medial side of the tympanic membrane.
peripheral
The ___ nervous system carries brain and spinal cord signals to other organs
b. peripheral
The ___ nervous system carries brain and spinal cord signals to other organs a. autonomic b. peripheral c. central d. craniospinal e. efferent
ventricles
The ___ of the brain are continuous with one another, and with the central canal of the spinal cord.
Internal capsule
The ________ contains projection fibers that connect the cerebrum to other parts of the brain.
Endoneurium
The connective tissue wrap around an axon and its Schwann cell sheath is the
Perineurium
The connective tissue wrap that surrounds many axons to form a fascicle is the
Epineurium
The connective tissue wrap the surrounds many fascicles to form a nerve is the
both pupils retract even if only one eye is stimulated
The consensual light reflex refers to the fact that ___.
sensory transduction
The conversion of a sensation like touch or heat to a pattern of action potentials is called ___.
Pons
The corneal reflex is mediated by the
commuissural fibers
The corpus callosum is composed of
c. commissural fibers
The corpus callosum is composed of a. long association fibers b. short association fibers c. commissural fibers d. projection fibers e. ascending fibers
current
The flow of electrical charge from point to point.
e. all of them
The following nerves arise from the brachial plexus and carry motor signals to muscles of the upper limb. Which of them carry sensory signals back to the CNS a. the axillary nerve b. the radial nerve c. the ulnar nerve d. the median nerve e. all of them
hold the lens of the eye in place
The function of the suspensory ligament is to ___.
synapse
The gap between one neuron and the next
astrocytes
The glial cell that contribute to the blood-brain barrier in the CNS are
Three horns
The gray matter of each halve of the spinal cord is divided into
Purkinje cells
The gray matter of the cerebellum contains 100 billion neurons. The most distinctive neuron, which is large and multipolar and receives input from more than 100,000 synapses, is called the
medulla oblongata
The gustatory nucleus, which receives taste signals from the tongue, is in the ___.
d. speech
The hypothalamus plays a role in controlling all of the following except a. sex drive b. hunger c. sleepiness d. speech e. blood pressure
D, speech
The hypothalamus plays a role in controlling all of the following except: A. sex drive, B. hunger, C. sleepiness, D. speech, E. blood pressure.
pia matter; terminal filum
The innermost meninx around the spinal cord is called the ___ and extends beyond the medullary cone as a ___.
pia mater; terminal filum
The innermost menix around the spinal cord is called the ___ and extends beyond the medullary cone as the ___.
tectorial membrane
The sensory cells of hearing are stimulated by the ___ resting on their stereocilia.
neurilemma
The sheath of Schwann.
ipsilateral
To describe a reflex arc as ___ means that its receptors and effectors are on the same side of the body
tactile (Merkel) discs; Ruffini corpuscles
Tonic receptors for light touch, textures, edges, and shapes are ___, and tonic receptors for heavy touch, pressure, stretching of the skin and joint movements are ___.
cupula
We sense rotary movements of the hand when the endolymph pushes on a gelatinous cap called the __ in a semicircular duct.
tracts
What are bundles of nerve fibers traveling up or down the white matter of the spinal cord?
ependymal cells
What are ciliated CNS neuroglia that play an active role in moving the cerebrospinal fluid?
neuroglia (glial cells)
What are closely associated with neurons, providing a protective and supportive network?
the movement of ions across cellular membranes
What are electrical currents due to in the body?
hypothalamus
What are sleep patterns regulated by?
sensory (afferent), motor (efferent), interneurons (association neurons)
What are the three functional classes of neurons?
multipolar, bipolar, unipolar
What are the three structural classes of neurons?
channel-linked receptors and g protein-linked receptors
What are two main types of neurotransmitter receptors?
Optic disc
What area of the retina contains the least amount of photoreceptors?
Subarachnoid space
What area of the spinal cord contains cerebrospinal fluid?
voltage-gated channels
What channels open in response to a change in membrane potential?
mechanically gated channels
What channels open when a membrane receptor is physically deformed?
chemically gated (ligand-gated) channels
What channels open when the appropriate chemical binds?
basic pattern of the CNS
What consists of a central cavity surrounded by a gray matter core, external to which is white matter?
Longitudinal fissure
What divides the cerebrum into right and left hemispheres?
whether the effects are excitatory or inhibitory, and whether the effects are direct or indirect
What do functional classifications of neurotransmitters consider?
changes in membrane potential
What do neurons use as communication signals?
neurons
What function optimally for a lifetime, are mostly amitotic, and have an exceptionally high metabolic rate requiring oxygen and glucose?
ions diffuse across the membrane, creating electrical currents
What happens when ion channels are open?
the cell
What has many gated ion channels?
neurotransmitters
What has several chemical classes?
Calcium and sodium
What ion channels are opened to produce an action potential in olfactory neurons?
Potassium
What ion produces depolarization in the stereocilia of the macula?
cauda equina
What is a bundle of nerve roots within vertebrae L2-S5 which innervate the pelvic organs and legs?
Nerve impulse
What is a change in the difference in positive and negative ions on the outer and inner surfaces of the neuron membrane? A change that opens adjacent channels and propagates its flow?
an automatic, involuntary response
What is a reflex action?
myelin sheath
What is a whitish, fatty, segmented covering that protects, insulates, and increases conduction velocity of axons?
spinal reflexes
What is an example of serial processing?
stimulus intensity
What is coded in the frequency of action potentials?
current
What is dependent on voltage and resistance?
Cochlear duct
What is found between the vestibular membrane and the basilar membrane of the cochlea?
Cerebrospinal fluid
What is found in the subarachnoid space?
Vitreous humor
What is found in the vitreous chamber of the eye?
resting membrane potential
What is generated by differences in ionic makeup of intracellular and extracellular fluids, and differential membrane permeability to solutes?
neurotransmitters
What is one of the ways neurons communicate?
neuron cell membrane
What is polarized, being more negatively charged inside than outside?
synaptic delay
What is related to the period of time required for release and binding of neurotransmitters?
the refractory period of an axon
What is related to the period of time required so that a neuron can generate another action potential?
Na+ gates opening; K+ gates opening; Na+ gates closing
What is the correct sequence of voltage-regulated gates opening and closing in an action potential?
carry impulses toward a cell body
What is the function of dendrites?
Killing bacteria
What is the function of lysozyme in the eyes?
Equalizes pressure on tympanic membrane in the middle ear
What is the function of the auditory tube?
Constriction of airways
What is the function of the parasympathetic division?
Stops the sound waves from reflecting back toward the cochlear canal
What is the function of the round window?
Dilate the pupil
What is the function of the sympathetic division?
generates and conducts nerve impulses away from the cell body to the axon terminal
What is the purpose of the single axon of neurons?
destroy ACh a brief period after its release by the axon endings
What is the role of acetylcholinesterase?
ATP-dependent "motor" proteins such as kinesin, dynesin, and myosin.
What mechanism is responsible for axon transport?
Mandibular branch of the trigeminal nerve
What nerve is generally used for dental anesthesia of the lower jaw?
an enhanced release of neurotransmitter
What results after synaptic potentiation occurs?
synaptic potentiation
What results when a presynaptic cell is stimulated repeatedly or continuously?
presynaptic inhibition
What results when another neuron inhibits the release of excitatory neurotransmitter from a presynaptic cell?
Cerebral aqueduct
What structure connects the third and fourth ventricles?
Ampulla of the semicircular canals
What structure is associated with dynamic balance?
Reticular activating system
What structure plays a major role in consciousness and sleep-wake cycles?
Central
What structure separates the frontal from the parietal lobe?
Tympanic membrane
What structure separates the outer ear from the middle ear?
Filum terminale and denticulate ligaments
What structures help to anchor the spinal cord within the subarachnoid space?
Limbic system
What system is involved in basic survival functions and emotions?
peripheral nervous system
What system is outside the central nervous system?
Beta
What type of brain waves are observed when a person is mentally very active?
Projection fibers
What type of fibers are continuations of the fibers in the spinal cord?
Commissural fibers
What type of fibers connect one hemisphere to the other?
Free nerve endings
What type of general sense receptors are the simplest and most common?
Sensory memory
What type of memory lasts for less than a second while the brain is receiving and evaluating input?
Thermoreceptors
What type of receptors respond to temperature changes?
Somatic general senses
What type of senses are found in the skin, muscles and joints?
REM (rapid eye movement) sleep
What type of sleep allows the brain to analyze events or eliminate meaningless information?
NREM (non-rapid eye movement) sleep
What type of sleep is considered restorative?
Retinal
What visual pigment is found combined with opsin in cones?
axons
When a finger or other appendage is severed in an accident, it is possible to surgically rejoin most tissues (bone, skin, etc.) and most will grow back together. However, in a cut through an appendage nerve, it is currently more difficult to reconnect what are primarily severed
Voltage-regulated Na+ gates open
When a neuron is depolarized to threshold,
true
When a pregnant woman takes folic acid she decreases the chance that her baby will have spina bifida
generator potential
When a sensory neuron is excited by some form of energy, the resulting graded potential is called a(n) ___.
potassium
When a tip link opens the ion channel on a cochlear stereo-cilium, ___ ions rapidly enter and depolarize the hair cell.
D. Control of the autonomic nervous system
Which of the following is NOT a function of the thalamus? A. Regulation of skeletal muscles / B. Limbic system and emotions / C. Perception of pain / D. Control of the autonomic nervous system
B. Phrenic
Which of the following is NOT a main nerve of the brachial plexus? A. Median, B. Phrenic, C. Musculocutaneous, D. Ulnar, E. Radial
c. they are mitotic
Which of the following is NOT a special characteristic of neurons? A. they conduct impulses B. they have extreme longevity C. they are mitotic D. they have an exceptionally high metabolic rate
C. Increased secretions in the digestive tract
Which of the following is NOT a typical "flight or fight" response by the sympathetic division of the ANS? A. Vasoconstriction of abdominal blood vessels / B. Dilation of air passageways / C. Increased secretions in the digestive tract / D. Increased fat break down for energy
B. Cochlea
Which of the following is NOT an auditory ossicle? A. Incus, B. Cochlea, C. Stapes, D. Malleus
A. Thalamus
Which of the following is NOT part of the brainstem? A. Thalamus / B. Pons / C. Medulla oblongata / D. Midbrain
b. a nerve impulse occurs if the excitatory in inhibitory effects are equal
Which of the following is false or incorrect? a. an excitatory postsynaptic potential occurs if the excitatory effect is greater than the inhibitory effect but less than threshold. b. a nerve impulse occurs if the excitatory in inhibitory effects are equal. c. an inhibitory postsynaptic potential occurs if the inhibitory effect is greater than the excitatory, causing hyper polarization of the membrane.
E. cholinesterase
Which of the following is not a neurotransmitter? A. GABA B. norepinephrine C. acetylcholine D. dopamine E. cholinesterase
c. they increase amplitude as they move away from the stimulus point
Which of the following is not true of graded potentials? a. they are short-lived b. they can form on receptor endings c. they increase amplitude as they move away from the stimulus point d. they can be called postsynaptic potentials
D. 5 roots, 3 trunks, 6 divisions, 3 cords, 5 nerves
Which of the following is the correct sequence of branching of the brachial plexus? A. 5 roots, 5 nerves, 3 trunks, 6 divisions, 3 cords / B. 5 nerves, 3 cords, 6 divisions, 3 trunks, 5 roots / C. 6 divisions, 5 roots, 5 nerves, 3 cords, 3 trunks / D. 5 roots, 3 trunks, 6 divisions, 3 cords, 5 nerves
proprioceptors
Which of the following nerve endings are not found in the skin? proproiceptors, Ruffini's corpuscles, tactile corpuscles, pacinian corpuscles, hair receptors
C. Action potentials cannot be triggered again until the hyperpolarized membrane returns to resting potential.
Which of the following statements is not true about an action potential? A. action potentials follow an all-or-none law. B. Action potentials are non-decremental; they do not get weaker with distance. C. Action potential cannot be triggered again until the hyper-polarized membrane returns to resting potential. D. Action potential are irreversible; once the neuron reaches threshold the action potential goes to completion. E. Action potentials cannot be generated unless a cell reaches threshold.
Arrector pili muscle
Which organs receive sympathetic innervation, but NOT parasympathetic?
Rods
Which photoreceptors are responsible for low-light and noncolor vision?
C. Lumbar plexus - T10 to L5
Which plexus is NOT correctly matched to its spinal nerve makeup? A. Cervical plexus - C1 to C4, B. Brachial plexus - C5 to T1, C. Lumbar plexus - T10 to L5, D. Sacral plexus - L4 to S4, E. Coccygeal plexus - S5 to Co
bipolar neurons
Which structural class of neuron have a single axon and dendrite?
unipolar neurons
Which structural class of neuron have a single process extending from the cell body that is associated with receptors at the distal end?
pyramidal cells in Wernicke's area
Your comprehension of these written words involves activity of ___.
side-to-side stability
Your spinal cord was unable to form any denticulate ligaments. Your spinal cord would most likely lose
astrocytes
___ are found in the CNS and and bind axons and blood vessels to each other.
multiple sclerosis
___ is a disease that gradually destroys the myelin sheaths of neurons in the CNS, particularly in young adults.
sound
a pressure disturbance produced by a vibrating object and propagated by the molecules of the medium
learning
causes changes in neuronal RNA, dendritic branching, deposition of unique proteins at LTM synapses, increase of presynaptic terminals, increase of neurotransmitter, and development of new neurons in the hippocampus.
basal nuclei
consist of a group of subcortical nuclei, which play a role in motor control and regulating attention and cognition.
preganglionic axons
extend from the CNS nearly all the way to the structures to be innervated, where they synapse with ganglionic neurons in the terminal ganglia
spiral, snail-shaped cochlea
extends from the anterior part of the vestibule and contains the cochlear duct
reticular formation
extends through the brain stem, keeping the cortex alert via the reticular activating system, and dampening familiar, repetitive, or weak sensory inputs.
posterior segment (cavity)
filled with a clear gel called vitreous humor that transmits light, supports the posterior surface of the lens, holds the retina firmly against the pigmented layer, and contributes to intraocular pressure
anterior segment (cavity)
filled with aqueous humor that supplies nutrients and oxygen to the lens and cornea while carrying away wastes
cerebellar processing
follows a functional scheme in which the frontal cortex communicates the intent to initiate voluntary movement to the cerebellum
dissolved in saliva, move into the taste pore, and contact a gustatory hair
for a chemical to be tasted it must be
terminals of the somatic motor fibers that innervate voluntary muscles
form elaborate neuromuscular junctions with their effector cells and they release the neurotransmitter acetylcholine
crista ampullaris
found in the ampulla of the semicircular canals and activated by head movement
afferent fibers carrying taste information from the tongue
found primarily in the facial nerve and glossopharyngeal cranial nerves
unencapsulated dendritic endings
free, or naked, nerve endings, and detect temperature, pain, itch, or light touch
reflexes
unlearned, rapid, predictable motor responses to a stimulus, and occur over highly specific neural pathways
touch
which sensory function involves neurons in the dorsal root ganglia?
eyelids (palpebrae), eyelashes, and their associated glands
help to protect the eye from physical danger as well as from drying out
rods
highly sensitive and are best suited to night vision
vestibulocochlear nerves (cranial nerve VIII)
nerves that are responsible for hearing and balance
optic nerves (cranial nerve II)
nerves that are responsible for vision
vagus nerves (cranial nerve x)
nerves that control several visceral organs
glossopharyngeal nerves (cranial nerve IX)
nerves that control the tongue and pharynx
olfactory nerves (cranial nerve I)
nerves that detect odors
accessory nerves (cranial nerve XI)
nerves that have a relationship with the vagus nerves
hypoglossal nerves (cranial nerve XIII)
nerves that innervate muscles of the tongue
receptor level
processing at this level involves a stimulus that must excite a receptor in order for sensation to occur
perceptual level
processing at this level involves interpretation of sensory input in the cerebral cortex
circuit level
processing at this level is involved with delivery of impulses to the appropriate region of the cerebral cortex for stimulus localization and perception
conjunctiva
produces a lubricating mucus that prevents the eye from drying out
perception of pain
protects the body from damage, and is stimulated by extremes of pressure and temperature, as well as chemicals released from damaged tissues
serotonin
prozac (fluoxetine) is an antidepressant that blocks the synaptic reuptake of
above level c5
quadriplegia (or paralysis of all 4 limbs) results from lesions on what part of the spine?
posterior association area
receives input from all sensory areas, integrating signals into a single thought.
crista ampullaris
receptor for dynamic equilibrium
simple or complex
receptor may be classified according to structural complexity and may be
mechanoreceptors, thermoreceptors, photoreceptors, chemoreceptors, nociceptors
receptors may be classified according to their location or location of stimulus, and include
outer pigmented layer
region of the retina that absorbs light
inner neural layer
region of the retina that contains millions of photoreceptors (rods, cones) that transduce light energy
thoracic splanchnic nerves; adrenal cortex
some fibers of the ___________ terminate by synapsing with the hormone-producing medullary cells of the _________.
hinton's law
states that any nerve serving a muscle that produces movement at a joint also innervates the joint and the skin over the joint
taste
strongly influenced by smell and stimulation of thermoreceptors, mechanoreceptors, and nociceptors.
sympathetic division
supplies the visceral organs in the internal body cavities but also all visceral structures in the somatic part of the body
ganglia
collections of neuron cell bodies associated with nerves in the PNS
midbrain
comprised of the cerebral peduncles, corpora quadrigemina, and substantia nigra
Withdrawal
Pulling the arm back from a hot pan is an example of a ______ reflex.
declarative memory
entails learning explicit information, is often stored with the learning context, and is related to the ability to manipulate symbols and language.
nondeclarative memory
entails motor skills, is often stored without details of the learning context, and is reinforced through performance.
preganglionic fibers from t5 down
enter and leave the sympathetic chains without synapsing
pigment breakdown
exposure of the photoreceptors to light causes
true
Sensory signals from the inner ear travel by way of the vestibuloccochlear nerve
cerebellum
The ___ helps coordinate and smooth skeletal movements.
d. cerebellum
The ___ helps to coordinate and smooth skeletal movements a. thalamus b. forebrain c.pons d. cerebellum e. limbic system
Foramen magnum
The spinal cord begins at the level of the
d. pelvic
The spinal cord id divided into all of the following regions except a. cervical b. thoracic c. lumbar d. pelvic e. sacral
Ipsilateral cerebellum
The spinocerebellar tracts carry unconscious proprioception to the
gamma motor neurons
The tension in a muscle spindle is maintain by
inferior to the corpus callosum
The third ventricle of the brain is ___.
olfactory cells
These cells are the only neurons in the body exposed to external environment, and unlike most neurons, they are replaceable.
electrical synapses
These have neurons that are electrically coupled via protein channels and allow direct exchange of ions from cell to cell.
action potentials
What are all-or-none phenomena?
neuromodulation
What occurs when a neurotransmitter acts via slow changes in target cell metabolism, or when chemicals other than neurotransmitter modify neuronal activity?
a single type of channel will open, permitting simultaneous flow of sodium and potassium
What occurs when an excitatory postsynaptic potential (EPSP) is being generated on the dendritic membrane?
motor neuron
What part of a simple reflex takes the message away from the CNS?
Habenular
What part of the diencephalon is involved with emotional and visceral responses to odors?
Mammillary bodies
What part of the hypothalamus are involved in emotional responses to odors, olfactory reflexes and memory?
Choroid plexuses
What produces cerebrospinal fluid?
Lacrimal apparatus
What structure produces tears?
B. sensory neuron-delivers signals to control sensory organs such as eye movement
Which is NOT a correct association of structure and function? A. axons-outgoing signals B. sensory neuron-delivers signals to control sensory organs such as eye movement C. cell body-nucleus and organelles D. interneuron- sums up input before sending signals to muscle or gland
cerebellum
Which is most concerned with motor coordination and equilibrium?
occipital lobe
Which lobe of the cerebrum is most concerned with vision?
somatic
Which nerve fibers innervate the skin and skeletal muscles?
autonomic nervous system
Which nervous system is an involuntary system?
e. vestibulocochlear
Which of the following cranial nerves carries equilibrium messages a. facial b. abducens c. trigeminal d. glossopharyngeal e. vestibulocochlear
B. Hypoglossal nerve
Which of the following cranial nerves does NOT carry taste impulses to the brain? A. Facial nerve / B. Hypoglossal nerve / C. Glossopharyngeal nerve / D. Vagus nerve
A. Vestibulospinal
Which of the following descending tracts is NOT a direct pathway to muscles for conscious, skilled movements? A. Vestibulospinal / B. Anterior corticospinal / C. Corticobulbar / D. Lateral corticospinal
D. CNS - always excitatory; ANS - always inhibitory
Which of the following differences between the central nervous system and the autonomic nervous system is incorrect? A. CNS - one neuron to effector; ANS - two neurons to effector / B. CNS - innervates skeletal muscle; ANS - innervates smooth and cardiac muscles and glands / C. CNS - axons myelinated; ANS - preganglionic axons myelinated, postganglionic axons unmyelinated / D. CNS - always excitatory; ANS - always inhibitory
c. gland
Which of the following is an effector a. afferent neuron b. efferent neuron' c. gland d. sense organ e. interneuron
e. the cerebellum
Which of the following is most concerned with motor coordination and equilibrium a. the precentral gyrus b. the postcentral gyrus c.the pons d. the hypothalamus e. the cerebellum
photoreceptors
contain a light-absorbing molecule called retinal
taste sensation
each has its own special mechanism for transduction
dorsal root and a ventral root
each spinal nerve connects to the spinal cord by a
tympanic membrane
airborne sound entering the external acoustic meatus strikes the _____ ____ and sets it vibrating.
olfactory cortex
allows detection of odors
gustatory cortex
allows perception of taste stimuli
primary somatosensory cortex
allows spatial discrimination and the ability to detect the location of stimulation.
short-term (working) memory
allows the memorization of a few units of information for a short period of time.
parasympathetic division
keeps body energy use as low as possible while directing digestion and elimination activities
taste disorders
less common but may be caused by respiratory tract infections, head injuries, chemicals, medications, or head and neck radiation.
cones
less sensitive to light and are best adapted to bright light and color vision
rami
lie distal to and are lateral branches of the spinal nerves that carry both motor and sensory fibers
taste buds
located in the oral cavity, with the majority located on the tongue
synapses
nervous signals pass from neuron to neuron over junctions called
acetylcholine
neurotransmitter released by the somatic motor neurons
cerebrovscular accidents (CVAs) or strokes
occur when blood supply to the brain is blocked, resulting in tissue death
transduction of sound stimuli
occurs after the trapped stereo cilia of the hair cells are deflected by localized movements of the basilar membrane
refraction of a light ray
occurs when it meets the surface of a different medium at an oblique angle rather than a right angle
hyperopia (farsightedness)
occurs when objects are focused behind the retina and results in seeing distant objects clearly but close objects are blurred
myopia (nearsightedness)
occurs when objects focus in front of the retina and results in seeing close objects without a problem but distant problems are blurred
visual processing
occurs when the action of light on photoreceptors hyper polarizes them, which causes the bipolar neurons from both rods and cones to ultimately send signals to their ganglion cells
dark adaptation
occurs when we go from a well-lit area into a dark one
light adaptation
occurs when we move from darkness into bright light
anosmias
olfactory disorders resulting from head injuries that tear the olfactory nerves, nasal cavity inflammation, or aging.
thorax
only here are the ventral rami arranged in a simple segmental pattern corresponding to that of the dorsal rami
brain waves
patterns of electrical activity
thalamus
plays a key role in mediating sensation, motor activities, cortical arousal, learning, and memory
sacral and lumbar plexuses
plexuses that overlap
sympathetic division
prepares the body to respond to an energy or threatening situation (or vigorous exercise)
resonance of the basilar membrane
processes sound signals mechanically before they ever reach the receptors
eyebrows
short, coarse hairs overlying the supraorbital margins of the eye that shade the eyes and keep perspiration out
brachial plexus
situated partly in the neck and partly in the axilla and gives rise to virtually all the nerves that innervate the upper limb
sensory receptors
specialized to respond to changes in their environment called stimuli
Alpha or beta receptors
Adrenergic receptors on effectors are called
false
Afferent fibers carry message to the muscles
thalamus
Almost all sensory signals pass through the ___ on the way to the cerebellum.
b. thalamus
Almost all sensory signals pass through the ___ on the way to the cerebrum a. corpora quadrigemina b. thalamus c. hypothalamus d. corpus callosum e. corticospinal tracts
L1
Around which vertebra does the spinal cord end?
Blood pressure, Heart rate, Digestion
Autonomic reflexes are used by the body to help regulate
Diverging circuits
Because of ___, one motor neuron of the brain can ultimately cause thousands of muscle fibers to contract.
endoneurium
Because of the absence of ___, damaged nerve fibers in the CNS cannot regenerate.
dendrites
Cell processes that are the receptive regions of the cell.
E, to help cool the brain
Cerebrospinal fluid serves all of the following functions except A. to support the weight of the brain, B. to cushion the brain from blows, C. to remove metabolic wastes from the central nervous system, D. to provide a stable chemical environmental for the nervous tissue, E. to help cool the brain.
depolarizations; hyperpolarizations
Changes in membrane potential relative to resting membrane potential can either be ___ or ___.
divirging (amplifying) circuits
Characterized by an incoming fiber that trigger responses in ever-increasing numbers of fibers along the circuit.
Muscarinic receptors
Cholinergic receptors on ANS effectors are called
ganglia
Collections of nerve cell bodies outside the central nervous system.
a. has more local specific effects
Compared to the endocrine system the nervous system usually a. has more local specific effects b. reacts more slowly to a stimulus c. does not employ chemical messengers d. continues to respond long after the stimulus ceases e secretes chemical messengers into the bloodstream
reflexes
Coordinators of simple, repeated actions.
recognize and name familiar objects
Damage to the temporal lobe would most likely cause the individual to be unable to
critical minimum (threshold) depolarization
Defined by the amount of influx of Na+ that at least equals the amount of efflux of K+.
intrafusal fibers
In skeletal muscle the stretch receptors are the
temporal and spatial summation
In what two ways is summation by the postsynaptic neuron accomplished?
the interior is negatively charged and contains less sodium
In what way does the interior surface of a cell membrane of a resting (nonconducting) neuron differ from the external environment?
a.temporal summation
In____ several EPSP's occurring in quick succession depolarize a neuron to threshold a.temporal summation b. spatial summation c. synaptic potentiation d. a reverberating circuit e. recruitment
c. neural integration
In____the additive effects of EPSP's and IPSP's determine whether a neuron fires. a. synaptic potentiation b. facilitation c. neural integration d. neural coding e. neuromodulation
j (muscle spindle)
Location of intrafusal fibers
receptor potentials
Meissner's, or tactile, corpuscle in your fingers respond to the texture by causing graded voltage changes across their plasma membranes. These voltages are called ___.
olfactory cells
Mitral cells synapse with
thalamus; cerebellum
Most somesthetic signals (touch, pain, heat, cold, pressure, movement, and stretch) below the head are carried by way of 3 neurons called the first-, second-, and third-order neurons. Generally, second-order neurons end in the ___; proprioceptive signals are an exception with their second-order neurons ending in the ___.
fast anterograde transport
Movement of mitochondria, synaptic vesicles, calcium ions, glucose, and amino acids from the soma down the axon is called
help form the blood-brain barrier
One role of the astrocytes is to
norepinephrine
"Feel-good" neurotransmitter.
the action potential jumps from node to node
"Saltatory" conduction occurs when
one axon and one dendrite arising from the soma
A bipolar neuron has
norepinephrine
A neurotransmitter whose function depends on a second messenger
Parasympathetic reduction of heart rate and sympathetic dilation of blood vessels
A sudden increase in blood pressure detected by baroreceptors in the walls of large arteries near the heart will cause
special senses
All receptors for ___ are confined to the head and are innervated by cranial nerves.
myelin sheath
An action potential carried in one nerve fiber cannot stimulate adjacent never fibers carried in the same nerve because of the
longitudinal fissure
Cerebral hemispheres are separated along the midline by the
transverse cerebral fissure
Cerebral hemispheres are separated from the cerebellum along the
d (central pattern generators)
Coordinators of simple repeated action
relative refractory period
During its ___, a neuron responds only to stimuli stronger than a normal threshold stimulus
Na+ is entering the neuron
During the rising phase of an action potential
the impulse would spread bidirectionally
If a motor neuron in the body were stimulated by an electrode placed about midpoint along the length of an axon...
the stimulus was stronger
If a nerve fiber is firing 300 times per second at time A and 500 times per second at time B, it probably means that at time B
true
If a neuron becomes hyperpolarized it is less likely to fire
Diverging
In a ___ neuronal circuit, input to one neuron leads to output from multiple neurons.
absolute refractory period
In this period, the neuron cannot respond to a stimulus no matter how strong.
ventricles
Lined with ependymal cells, and are filled with cerebrospinal fluid.
cerebellum
Purkinje cells are giant multipolar neurons of the ___.
Spatial summation
Stimulation of a postsynaptic neuron by many terminals at the same time.
TRUE
T/F: Enkephalins and endorphins are peptides that act like morphine.
lacrimal glands
Tears are produced by the ___.
rough endoplasmic reticulum
The Nissl bodies of a neuron consist of
oval window
The footplate of the stapes covers an opening called the ___.
Anterior thigh and leg
The major nerves from the lumbar plexus serve the
subarachnoid space
The majority of cerebrospinal fluid in the spinal cord is found here.
cerebellum; coordinate skeleltal muscles. *
The second-largest region of the brain is the ___, whose function is to
c. the thoracic region
The ventral rami of the spinal nerves form nerve plexuses in all regions except a. the cervical region b. the brachial region c. the thoracic region d. the lumbar region e. the sacral region
motor; sensory
The ventral root carries ___ neurons, while the dorsal roots carries ___ neurons.
afferent fibers
These nerve fibers conduct sensory signals to the central nervous system.
basal nuclei
Unwanted muscle contractions are inhibited by
e. cell walls
Which of the following does not pertain to neurons? A. sodium pumps B. Schwann cells C. myelin D. nodes of Ranvier E. cell walls
trichromatic vision
Which of the following is not characteristic of rod vision?
a. tectospinal
You hear a loud noise and instinctively react to it. What motor tract carried the signals? a. tectospinal b. lateral corticospinal c. ventral corticospinal d. spinothalamic e. spinocerebellar
phasic receptors
You walk into a restaurant and smelled barbecued ribs. Within a few seconds, however, you are no longer aware of the smell. Your olfactory receptors are ___.
cerebellum
You were driving erratically and a police officer pulled you over. The officer requested that you get out of the car and perform two activities. The first was to walk a straight line, and the second was to close your eyes and touch your nose with your index finger. The officer was checking on the ability of your ___ to coordinate these activities.
used synaptic vesicles and unused chemicals from the synaptic knobs up the axon to the soma
You were unable to produce the motor protein called dynein. Your neurons would be unable to transport
primary visual cortex and visual association area
allow reception and interpretation of visual stimuli.
olfactory receptors
bipolar neurons with a thin apical dendrite that terminates in a knob with several olfactory cilia
normal brain functions
can be recorded with an electroencephalogram, or EEG
lumbar plexuses
contribute to the sacral plexus via the lumbosacral trunk
anterior and posterior lobes
coordinate body movements
uncinate fits
olfactory hallucinations
maculae
sensory receptors for static equilibrium
peripheral motor endings
the PNS element that activates effectors by releasing neurotransmitters.
reflex arcs
the highly specific neural pathways of reflexes
retina
the inner layer of the eye
choroid, ciliary body, iris
three regions of the vascular tunic
70%
what percent of our body's sensory receptors are found in the eye
norepinephrine
A catecholamine
voltage
A measure of the amount of difference in electrical charge between two points.
broca's area
A motor speech area that controls muscles involved in speech production.
the long fibers of long axons
A nerve is composed of
choroid plexus; ependymal cells
A network of capillaries in the brain that produces cerebrospinal fluid is called the ___ and is surrounded
the threshold potential
A neuron fires only when its membrane reaches
association neuron
A neuron that has as its primary function the job of connecting other neurons.
resting potential
A neurotransmitter, such as Glycine, attaches to a ligand receptor and causes hyperpolarization. This neurotranmitter would most likely cause a(n)
c.withdrawal reflex
A nurse pricks your finger to type your blood. You flinch at the pain, pulling your hand back. This is called the a. pain reflex b. stretch reflex c.withdrawal reflex d.tendon reflex e. crossed extensor reflex
the membrane potential has been reestablished
A second nerve impulse cannot be generated until ___.
+35 mV
A typical neuron will have a membrane voltage of about __ at the time when sodium gates close and potassium ions begin rapidly leaving the cell.
dermatome
A/an __ is a region of the skin that provides sensory input to a particular spinal nerve
Inhibitory or excitatory
Acetylcholine binding to muscarinic receptors has a/an ______ effect, depending on the effector.
Thalamus
All sensory impulses except for smell are relayed through the
dorsal horn
All somatic sensory fibers from the neck down enter this region of gray matter of the spinal cord.
primary motor cortex
Allows conscious control of skilled voluntary movement of skeletal muscles.
meningitis
An individual is experiencing a high fever, stiff neck, drowsiness, and intense headache. A spinal tap showed bacteria and white blood cells in the cerebrospinal fluid (CSF). The individual most likely has
neurilemma
An individual peripheral nerve axon is covered by Schwann cells which produce a (an)
Subthreshold stimulus
An insufficient stimulus.
Threshold stimulus
Any stimulus below this intensity will result in no response in a neuron.
trigger zone
Area where nerve impulse is generated.
secretory zone
Axon terminals release neurotransmitters.
fourth week
By which week of pregnancy does the neural groove fuse, giving rise to the neural tube, which rapid idly differentiates into the CNS?
graded potentials
Can either be depolarizations or hyperpolarizations, and are critical to the generation of action potentials.
hypothalamus
Centers for hunger, thirst and thermoregulation are found in a part of the brain called the ___
archnoid villi
Cerebrospinal fluid is absorbed by these cauliflower like structures
lateral and medial apertures
Cerebrospinal fluid leaves the fourth ventricle of the brain by way of the ___.
c. the arachnoid villi
Cerebrospinal fluid returns to the bloodstream by way of a. the central canal of the spinal cord b. the choroid plexuses of the brain c. the arachnoid villi d. the cauda equine e. the pia mater
arachnoid villi
Cerebrospinal fluid returns to the bloodstream by way of the
Nicotinic receptors
Cholinergic receptors on skeletal muscles and postganglionic neurons in the ANS are called
converging circuits
Circuits common in sensory and motor pathways.
divirging (amplifying) circuits
Circuits common in sensory and motor pathways.
has more local, specific effects
Compared to the endocrine system, the nervous system usually
pons
Contains fiber tracts that complete conduction pathways between the brain and spinal cord.
false
Contralateral tracts are those that do not decussate
frontal eye field
Controls eye movement
the extrinsic muscles
Convergence of the eyes when focusing on a nearby object is achieved by means of
neural coding
Conversion of information to a meaningful pattern of action potentials
crossed extensor
During a withdrawal reflex of the leg, a ___ reflex also occurs to prevent a person from falling over.
three weeks
During which week of gestation does the endoderm form the neural plate*? *which invaginates, forming the neural groove, flanked on either side by neural folds.
help to circulate the cerebrospinal fluid
Ependymal cells ___.
c. the thalamus
Fibers of the optic nerve terminate mainly in a. the frontal lobes b.the occipiital lobes c.. the thalamus d. the midbrain e. the optic chiasma
l (perineurium)
Fibrous sheath enclosing a nerve
frontal, parietal, temporal, occipital, insular
Five lobes of the brain separated by specific sulci.
wernice's area
Fluent aphasia is associated with the destruction of this area
e (gyri)
Folds and wrinkles of the cerebral surface
repolarization
Follows depolarization along the membrane.
Prefrontal area
Forethought, motivation and emotional regulation occurs in the
neuronal pools
Functional groups of neurons that integrate incoming information from receptors.
cell bodies of neurons in the PNS
Ganglia consist of
ependymal cells
Glia cells which resemble a cuboidal epithelium without the basement membrane and produce cerebrospinal fluid (CSF) are called
basilar membrane
Hair cells of the cochlea are stimulated as a result of the up-and-down vibrations of the
a (postentral gyrus)
Has an upside-down sensory map of the opposite side of the body
cerebral cortex
Has several motor areas located in the frontal lobes, which control voluntary movement.
from 20 to 20,000 Hz
Humans can hear sounds ranging in frequency from ___ to ___.
Convex lens
Hyperopia can be corrected with
IPSP
Hyperpolarization of a dendrite by a neurotransmitter
beta waves
If we recorded your electroencephalogram while you took this test, it would show predominantly
c. medulla oblongata
If you feel a vibration or a deep touch, the sensory signals would decussate in which structure a. spinal cord b. pons c. medulla oblongata d. midbrain e. not at all
sodium ions flowing down the fiber under the axolema to the next adjacent node of Ranvier
In a myelinated neuron carrying an action potential, the next node of Ranvier will be stimulated by
meningeal branch
In addition to the dorsal and ventral rami, each spinal nerve gives rise to a
synaptic vesicles fuse with the presynaptic membrane, and neurotransmitters diffuse across the synaptic cleft
In order for transmission across the synapse to occur
diverging circuit
Involved in activating fibers of a skeletal muscle such as the biceps muscle.
reverberating circuit
Involved in control of rhythmic activities such as breathing.
Sclera
Is part of the fibrous tunic of the eye
false
Large nerve fibers conduct signals more slowly than small ones
paired lateral ventricles
Lie deep within each cerebral hemisphere, and are separated by the septum pellucidum.
fourth ventricle
Lies in the hindbrain and communicates with the third ventricle via the cerebral aqueduct.
third ventricle
Lies within the diencephalon, and communicates with the lateral ventricles via two inter ventricular foramina.
they obey all-or-none law
Local potentials differ from action potentials in all of these ways except that
f (ventral roots)
Location of afferent somas
microglia
Macrophages of the central nervous system
substance p
Mediates pain.
degrade serotonin after reuptake
Monoamine oxidase
diencephalon
Most lower motor neurons are located in the
ventral horn
Motor neurons of the somatic motor system have their nerve cell bodies, or somas, in the
retrograde transport
Movement of materials up an axon toward the soma
true
Myelinated nerve fibers conduct signal faster than unmyelinated fibers
mixed
Name of a type of nerve that transmits both sensory and motor information.
endorphins
Natural opiates that inhibit pain; effect mimicked by morphine.
are crucial for the development of neural connections
Nerve cell adhesion molecules (N-CAMs) ____.
Travel faster in large myelinated fibers
Nerve signals
postsynaptic cells
Neurons carrying impulses away from the synapse.
presynaptic cells
Neurons conducting impulses toward the synapse.
all or none
Neurons follow the ____ law. meaning they either fire at maximum voltage or not at all
either excite or inhibit the post synaptic neuron
Neurotransmitters are molecules that cross the synaptic cleft and
Temporal summation
Numerous nerve impulses arriving at a synapse at closely timed intervals exert a cumulative effect.
receptive region
Plasma membrane exhibits chemically gate ion channels.
secretory region
Plasma membrane exhibits voltage-gated Ca2+ channels.
facilitation
Process in which on presynaptic neuron makes it easier for another on to stimulate a postsynaptic neuron
cerebellum
Processes inputs from several strutters and coordinates skeletal muscle contraction to produce smooth movement.
receptive region
Receives stimuli.
phasic receptors
Receptors that respond intensely to the onset of stimulation but quickly stop responding are called ___.
r (annulospinal endings)
Responds to sustained stretch of a muscle spindle
repolarization
Restores resting membrane potential.
parallel processing
Results in inputs stimulating many pathways simultaneously, and is vital to higher level mental functioning.
the myelin sheath
Saltatory conduction is made possible by ___.
oligodendrocytes
Schwann cells are functionally similar to ___.
thalamus
Second-order neurons synapse with neurons in the
d. the synaptic cleft prevents an impulse from being transmitted directly from one neuron to another
Select the correct statement regarding synapses. a. cells with interconnected cytoplasm are chemically coupled b. the release of neurotransmitter molecules gives cells the property of being electrically coupled c. neurotransmitter receptors are located on the axons of cells d. the synaptic cleft prevents an impulse from being transmitted directly from one neuron to another
true
Sensations of pressure, light touch, and pain will travel up the spinothalamic tract
n (sulci)
Shallow grooves between the folds of the cerebrum
graded potentials
Short-lived, local changes in membrane potentials.
trigeminal nerve
Some strong odors are detected by the ___ instead of the olfactory cells.
o ( choroid plexus)
Source of cerebrospinal fluid
neurons
Specialized cells that conduct messages in the form of electrical impulses throughout the body.
chemical synapses
Specialized for release and reception of chemical neurotransmitters.
vertebrae c5 to c6 contains segments of the spinal cord, while vertebrae L3 to L5 do not
Spinal cord injuries commonly result from fractures of vertebrae c5 to c6, but never from fractures of L3 to L5. This is because
both sensory and motor fibers
Spinal nerves contain
Adrenal medulla
Splanchnic nerves that do not synapse in either the chain ganglion nor the collateral ganglion will synapse with specialized neurons in the
hearing
Stereo-cilia with tip links are involved in the sense of ___.
axon hillock
Summation occurs in the ___ of a neuron
semicircular ducts
Suppose you were sitting in a rotating chair in a hair salon with your eyes closed, and the chair was rotated. You could sense this by means of your ___.
b (Medulla oblongata)
Swallowing and gag reflexes
Organs in the thoracic cavity
Sympathetic postganglionic nerves that form sympathetic nerves supply
Skeletal muscle B. Smooth muscle and glands in the skin
Sympathetic postganglionic nerves that run with spinal nerves will serve
TRUE
T/F: A postsynaptic potential is a graded potential that is the result of a neurotransmitter released into the synapse between two neurons.
TRUE
T/F: A stimulus traveling toward a synapse appears to open calcium ion channels at the presynaptic end, which in turn promotes fusion of synaptic vesicles to the axonal membrane.
TRUE
T/F: Cell bodies of sensory neurons may be located in ganglia lying outside the central nervous system.
TRUE
T/F: During depolarization, the inside of the neuron's membrane becomes less negative.
TRUE
T/F: Efferent nerve fibers may be described as motor nerve fibers.
TRUE
T/F: If bacteria invaded the CNS tissue, microglia would migrate to the area to engulf and destroy them.
TRUE
T/F: In myelinated axons the voltage-regulated sodium channels are concentrated at the nodes of Ranvier.
circumvallate
Taste buds are found on all the lingual papillae except the ___ type.
spicy
Taste cells produce all of the following sensations except
somatic
That part of the nervous system that is voluntary and conducts impulses from the CNS to the skeletal muscles is the ___ nervous system.
a muscle that over-contracts to relax
The Golgi tendon reflex causes
reticular formation
The __ is a chain of nuclei in the brainstem that screen out unimportant stimuli and selectively allow other stimuli to come to one's conscious attention
medulla oblogata
The ___ contains nuclei that control coughing sneezing, swallowing, and vomiting.
e. medulla oblongata
The ___ contains nuclei that control coughing, sneezing, swallowing and vomiting a. thalamus b. hypothalamus c. midbrain d. pons e. medulla oblongata
b. hypothalamus
The ___ contains nuclei that regulate body temperature, food intake, and sexual response a. thalamus b. hypothalamus c. midbrain d. pons e. medulla oblongata
hypothalamus
The ___ contains nuclei that regulate body temperature, food intake, and sexual response.
Preganglionic
The _______________ neuron runs from the CNS and the autonomic ganglion.
Binocular vision
The ability to perceive depth and judge distance is due to
conditioned reflexes
The ability to recall and perform learned motor skills and habits is called ___.
the gray matter
The cell bodies of the cerebral neurons are located in
Brain stem and lateral gray horns of the sacral area of the spinal cord
The cell bodies of the parasympathetic preganglionic neurons are found in the
Lateral gray horns of T1 through L2 region of the spinal cord
The cell bodies of the sympathetic preganglionic neurons are in the
dermatome
The cutaneous regions innervated by specific spinal nerves are each called a
true
The deepest meninx is the pia mater
Sensory and has a ganglion
The dorsal spinal nerve root is
acetylcholinesterase
The enzyme that breaks down acetylcholine within the synaptic cleft.
adipose tissue
The epidural space in the spinal column is occupied by
photopic vision has higher resolution than scotopic vision
The fact that cone cells exhibit less neuronal convergence than rod cells do is part of the reason that ___.
the efflux of K+
The falling phase of an action potential results from
calcium ions enter the synaptic knob
The first event that occurs when a nerve signal reaches a synaptic knob is
solitary nucleus in the medulla oblongata
The first-order neurons of taste project to the ___.
Medulla oblongata
The gag reflex is mediated by the
neuron cell body (perikaryon or soma)
The major biosynthetic center containing the usual organelles except for centrioles.
falx cerebri
The meningeal layer of the dura mater folds inward to separate the left and right cerebral hemispheres.
astrocyte
The most abundant cell in the nervous system is the
multipolar; motor neurons and interneurons
The most common structural neuron is the ___ neuron, which includes
Cataracts
The most common visual problem of older persons that requires medical treatment is
fovea centralis
The most finely detailed images are produced by the _____.
C. Somatic motor neurons that connect the CNS to the digestive tract
The nerve plexuses of the enteric nervous system receive contributions from all of the following except A. Enteric neurons of the enteric plexuses / B. ANS neurons that connect the CNS to the digestive tract / C. Somatic motor neurons that connect the CNS to the digestive tract / D. Sensory neurons that connect the digestive tract to the CNS
Cauda equina
The nerves arising from the inferior lumbosacral enlargement form the
the prosencephalon (forebrain), mesencephalon (midbrain), and rhombencephalon (hindbrain)
The neural tube develops constrictions that divide into which three primary brain vesicles?
neural folds
The neural tube is formed by fusion of the
d. nerve signals pass from neuron to neuron over junctions called synapses
The neuron doctrine refers to the fact that a. action potentials are all or none b. neurons do not fire unless they reach threshold c. neurons are organized into functional groups called neuronal pools d. nerve signals pass from neuron to neuron over junctions called synapses e. once4 an action potentials begins it cannot be stopped
ectoderm; mesoderm
The neurons and all glial cells except microglia are derived from ___; the microglia are derived from ____.
central nervous system; form the myelin sheath
The oligodendrocyte is found in the ___ and functions to
optic chiasma
The optic nerve becomes the optic tract when it reaches the
axon
The part of a neuron that conducts impulses away from its cell body.
Visible light
The part of the electromagnetic spectrum that can be detected by the human eye is
absolute refractory period
The period after an initial stimulus when a neuron is not sensitive to another stimulus.
c. monosynaptic
The quickest reflex arcs involve only two neurons and are thus a. ipsilateral b. contrsalatersal c. monosynaptic d. polysynaptic e. autonomic
lamellated corpuscles
The receptors for deep pressure in the dermis and subcutaneous tissue are ___.
microvilli on the epithelial cells
The receptors for taste are located on the ___.
hair receptors
The receptors most likely to detect an ant crawling on your back are ___.
Convergence
The rotation of the eyes medially to view a close object is called
neurotransmitter
The substance released at axon terminals to propagate a nervous impulse.
m ( corpora quadrigemina)
The superior and inferior colliculi
Alongside the vertebral column from cervical through sacral regions
The sympathetic chain ganglion are located
Organs in the abdominal cavity
The sympathetic splanchnic nerves serve
electrical synapse
The synapse more common in embryonic nervous tissue than adults is the ___.
Insula
The taste cortex is located in the _____ lobe.
bitter
The threshold for this taste is the lowest for any other tastes.
enkephalins
The transmission of pain signals through the spinal cord can be prevented by ___.
e. axon hillock
The trigger zone of a neuron includes a. dendrites b. synaptic knob c. each node of Ranvier d. each internode e. axon hillock
initial segment
The trigger zone of a neuron includes the axon hillock and
longitudinal fissure
The two cerebral hemispheres are separated into right and left hemispheres by a deep groove called the
ventral horn of the spinal cord
The upper motor neurons that control the skeletal muscle are found in the
the ventral horn of the spinal cord
The upper motor neurons that control the skeletal muscles are found in
cerebrospinal fluid
The ventricles of the brain are filled with a fluid called
Occipital
The visual cortex is located in the _______ lobe.
arbor vitae
The white matter of the cerebellum constitutes its ___.
Arbor vitae
The white matter of the cerebellum is called the
Cerebral medulla
The white matter of the cerebrum is the
ependymal cells and astrocytes
There are two barrier systems to the blood supply of the brain: the blood-brain barrier (BBB) and the blood-CSF barrier. Two glial cells that are critical to the formation of these barriers are
alpha motor neurons
These neurons innervate extrafusal fibers.
channel-linked receptors
These receptors mediate direct transmitter action and result in brief, localized changes.
facial (VII) and glossopharyngeal (IX)
Two cranial nerves involved in taste are
alpha, beta, theta, delta
What are 4 types of brain waves?
Nociceptors
What type of receptors respond to painful stimuli?
autonomic nervous system
Which nervous system consists of visceral motor nerve fibers that regulate the activity of smooth muscle, cardiac muscle, and glands?
B. Midbrain
Which of the following is NOT part of the diencephalon? A. Hypothalamus / B. Midbrain / C. Thalamus / D. Subthalamus
B. Pigment cells
Which of the following is NOT part of the neural layer of the retina? A. Bipolar neurons / B. Pigment cells / C. Photoreceptors / D. Ganglionic neurons
D. It decreases the speed of nerve impulse conduction
Which of the following is NOT true about the myelin sheath? A. It is composed of layers of cellular membrane containing myelin around nerve fibers. B. It gives nerve fibers their white glistening appearance. C. It provides a pathway for new fiber growth if the axon is severed. D. It decreases the speed of nerve impulse conduction E. It is formed from Schwann cells.
b. some ions are prevented from moving down their concentration gradients by ATP-driven pumps
Which of the following is true about the movement of ions across excitable living membranes? a. ions always move actively across membranes through leakage channels b. some ions are prevented from moving down their concentration gradients by ATP-driven pumps c. sodium gates in the membrane can open in response to electrical potential changes d. the bulk of the solutions inside a cell are negatively charged
Bitter
Which primary odor serves to protect from poisons?
multipolar neurons
Which structural class of neuron has three or more processes?
true
Within one tract of the spinal cord all nerve fibers have the same function
s (reciprocal inhibition)
Would suppress contraction of the triceps brachii when the biceps brachii is contracting
dorsal root -> dorsal horn -> ventral horn -> ventral root -> spinal nerve
You are following the signals from a sensory neuron to the spinal cord where it synapses with a motor neuron that leaves the spinal cord and synapses on a skeletal muscle. The route would be
Ependymal cells
___ line the ventricles of the brain
graded
___ potentials are short-lived, local changes in membrane potential that can be either depolarized or hyper polarized.
a. association tracts
____ connect one gyrus to another within the same cerbral hemisphere a. association tracts b. projection tracts c. commissural tracts d. spinothalamic tracts e. corticospinal tracts
decussation
_____ is the crossing of ascending or descending nerve fibers from one side of the CNS to the other
monoamines (biogenic amines)
___________ are neurotransmitters, such as GABA, that are synthesized from amino acids.
crossed-extensor reflex
a complex spinal reflex consisting of an ipsilateral withdrawal reflex and a contralateral extensor reflex
nerve
a cordlike organ consisting of parallel bundles of peripheral axons enclosed by connective tissue wrappings
huntington's disease
a fatal hereditary disorder that results from deterioration of the basal nuclei and cerebral cortex
meniere's syndrome
a labyrinth disorder that causes a person to suffer repeated attacks of vertigo, nausea, and vomiting
blood-brain barrier
a mechanism that helps maintain a protective environment for the brain.
flocculonodular lobes
adjust posture to maintain balance
primary auditory cortex and auditory association area
allow detection of the properties and contextual recognition of sound.
deafness
any hearing loss, no matter how slight
sacral outflow
arises from neurons located in the lateral gray mater of the spinal cord segment S2-S4
sensory receptors
atrophy to some degree with age, and there is a decrease in muscle tone in the face and neck; reflexes occur a bit more slowly
perception of pitch, detection of loudness, and localization of sound
auditory processing involves
vestibule
central cavity of the body labyrinth with two membranous sacs suspended in the perilymph, the saccule and the utricle
receptors for taste and smell
chemoreceptors that respond to chemicals in solution
cerebellum
collects input concerning balance and tension in muscles and ligaments
cerebellar peduncles
communicate between the cerebellum and the brain stem
encapsulated dendritic endings
consist of a dendrite enclosed in a connective tissue capsule and detect discriminatory touch, initial, continuous, and deep pressure, and stretch of muscles, tendons, and joint capsules
autonomic nervous system
consists of a two-neuron chain
superficial reflexes
elicited by gentle cutaneous stimulation
consciousness
encompasses conscious perception of sensations, voluntary initiation and control of movement, and capabilities associated with higher mental processing.
sweet, sour, bitter, salty, umami
five basic taste sensations
12
how many pairs of cranial nerves originate from the brain?
four
how many stages are in non-rapid eye movement sleep (NREM)?
multiple sclerosis
in this disorder, oligodendrocytes and myelin sheaths of the CNS deteriorate and are replaced by hardened scar tissue.
stretch reflex
in this reflex, the muscle spindle is stretch and excited by either an external stretch or an internal stretch.
electromagnetic radiation
includes all energy waves from long waves to short waves, and includes the visible light that our eyes see as color
directly to reflex centers in the brain stem
information from the balance receptors goes ___________________________, rather than to the cerebral cortex.
flexor (withdrawal) reflex
initiated by a painful stimulus and causes automatic withdrawal of the threatened body part from the stimulus
cranial nerves
innervate muscles of the head in a similar way
autonomic nervous system
innervates cardiac an smooth muscle and glands
junctions between autonomic motor endings and the visceral effectors
involve varicosities and release either acetylcholine or epinephrine as their neurotransmitter
visceral association area
involved in conscious visceral sensation.
somatic sensory system
involves the receptor level, the circuit level, and the perpetual level
precommand level
made up of the cerebellum and the basal nuclei and is the highest level of the motor system hierarchy
retinal ganglion cells
merge in the back of the eyeball to become the optic nerve, which crosses at the optic chiasma to become the optic tracts
photoreceptors
modified neurons that structurally resemble tall epithelial cells
the ventral horn of the spinal cord
nerve fibers that stimulate the skeletal muscles of your foot have their somas in
oculomotor, trochlear, and abducens nerves (cranial nerves III, IV, and VI)
nerves that allow movement of the eyeball
facial nerves (cranial nerve VII)
nerves that allow movements of muscles creating facial expression
epinephrine and acetylcholine
neurotransmitters released by the autonomic nervous system; both may have either an excitatory or an inhibitory effect
vision
our dominant sense
dopamine
parkinson disease is caused by degeneration of neurons that release
golgi tendon reflex
produces muscle relaxation and lengthening in response to contraction
the brain stem
produces rigidly programmed, automatic behaviors necessary for survival.
semicircular canals
project from the posterior aspect of the vestibule, each containing an equilibrium receptor region called a crista ampullaris
axons from the thalamus
project through the internal capsule to form the optic radiation of fibers in the cerebral white matter
equilibrium sense
responds to various head movements and depends on input from the internal ear, vision, and information from stretch receptors of muscles and tendons
cerebral white matter
responsible for communication between cerebral areas and the cerebral cortex and lower CNS centers.
vestibular cortex
responsible for conscious awareness of balance
normal brain functions
results from continuous electrical activity of neurons
parkinson's disease
results from deterioration of dopamine-secreting neurons of the substantia nigra, and leads to a loss in coordination of movement and a persistent tremor
amplitude (height)
reveals a sound's intensity
optic tracts
send their axons to neurons within the lateral geniculate body of the thalamus
spinal reflexes
somatic reflexes mediated by the spinal cord
somatic nervous system
stimulates skeletal muscles
vagus nerve
taste impulses from the few taste buds found on the epiglottis and the lower pharynx are conveyed via the
far point of vision
that distance beyond which no change in lens shape is required (about 6 meters or 20 feet)
somatic nervous system
the cell bodies of the neurons are in the spinal cord and their axons extend to the skeletal muscles they innervate
hypothalamus
the control center of the body, regulating ANS activity, such as emotional response, body temperature, food intake, sleep-wake cycles, and endocrine function.
thalamus, hypothalamus, epithalamus
the diencephalon consists of
auricle (pinna) and the acoustic meatus
the external ear consists of the
visceral sensory neurons
the first link in autonomic reflexes, sends information concerning chemical changes, stretch, and irritation of the viscera
cerebrospinal fluid
the fluid found within the ventricles of the brain and surrounding the brain and spinal cord
pia mater
the innermost layer that clings tightly to the brain
wernicke's area, broca's area, the lateral prefrontal cortex, and the lateral and ventral parts of the temporal lobe
the language areas involved in comprehension and articulation
segmental level
the lowest level on the motor control hierarchy and consists of the spinal cord circuits
vascular tunic (uvea)
the middle layer of the eyeball
arachnoid mater
the middle meninx that forms a loose brain covering
dura mater
the most durable, outermost covering that extends inward in certain areas to limit movement of the brain within the cranium.
sciatic
the most vulnerable nerve in the body
endoneurium
the neurilemma is covered by the loose connective tissue called
frequency
the number of waves that pass a given point in a given time
olfactory epithelium
the organ of smell located in the roof of the nasal cavity
fibrous tunic
the outermost coat of the eye and is made of a dense avascular connective tissue
somatic sensory system
the part of the sensory system serving the body wall and limbs
dendrite
the portion of the neuron that receives signals from other neurons
photoreception
the process by which the eye detects light energy
summation
the process of adding up postsynaptic potentials and responding to their net effect
sacral outflow
the rest of the large intestine and pelvic organs are served by the
sacral; lumbar
the sciatic nerve comes from the ___ plexus, while the femor nerve comes from the ___ plexus.
taste buds
the sensory receptor organs for taste
corticospinal tracts
the signals that control your handwriting travel down the spinal cord in the
cervical, thoracic, lumbar, sacral
the spinal cord is divided into which regions?
the developing spinal cord and adjacent neural crest
the spinal nerves branch from
the forming vertebrae
the spinal nerves exit between
memory
the storage and retrieval of information
rhodopsin
the visual pigment of rods, formed and broken down within the rods (same for cones)
overlap
there is _____ between the somatic and autonomic nervous systems
chickenpox
this viral infestation can remain viable with the dorsal root ganglia for many years.
accommodation of the lens, constriction of the pupils, and convergence of the eyeballs
three adjustments demanded by the focusing for close vision
meninges
three connective tissue membranes that cover and protect the CNS, protect blood vessels, and enclose venous sinuses, contain cerebrospinal fluid, and partition the brain.
a high emotional state, repetition, association of new information with old, or the automatic formation of memory while concentrating on something else.
transfer of information from short-term to long-term memory can be affected by
concussion, contusion, and subdural or subarachnoid hemorrhage
traumatic head injuries can lead to which brain injuries
bony labyrinth, membranous labyrinth
two divisions of the internal ear
sclera and cornea
two regions of the fibrous tunic
outer pigmented layer, inner neural layer
two regions of the retina
gray rami communicantes
when synapses are made in chain ganglia, the postganglionic axons enter the ventral (or dorsal) ramus of the adjoining spinal nerves by way of communicating branches called
central pattern generators
which groups of neurons in the spinal cord controls walking?
left
which hemisphere of the brain often dominates language abilities, math, and logic?
right
which hemisphere of the brain often dominates visual-spatial skills, intuition, emotion, and artistic and musical skills?
intercostal nerve
which nerve is most important in relaying motor signals bringing about ventilation?
cervical
which nerve is sensory only?
action potential
Also called a nerve impulse transmitted by axons.
not open voltage-regulated gates and not fire an action potential
An excitatory local potential reaches the trigger zone at the axon hillock and causes a depolarization to -60 millivolts. The trigger zone will most likely
acetylcholine
An excitatory neurotransmitter secreted by motor neurons innervating the skeletal muscle.
synapse
An impulse from one nerve cell is communicated to another nerve cell via the ___.
hyperpolarization
An inhibitory postsynaptic potential (IPSP) is associated with ____.
true
Because of the decussation of sensory nerve fibers, the right postcentral gyrus monitors sensations from the left side of the body
cervical plexus
formed by the ventral rami of the first four cervical nerves
simple receptors
general senses, and may be unencapsulated or encapsulated dendritic endings
cerebrospinal fluid
gives buoyancy to the brain, protects the brain and spinal cord from impact damage, and is a delivery medium for nutrients and chemical signals.
projection level
has direct control of the spinal cord
cochlear duct
houses the spiral organ (of corti), the receptors for hearing
3
how many layers form the wall of the eyeball?
three
how many times is light bent when entering/leaving the cornea and lens?
glial cells; blood-brain barrier
most adult brain tumors are composed of ___ and cannot be treated by chemotherapy because of the ___.
skeletal muscle activity and visceral organ responses
most body responses to changing internal and external stimuli involve both ____ and ____
cerebral hemispheres
Form the superior part of the brain, and are characterized by ridges and groves called gyri and sulci.
dura mater; arachnoid, pia mater
From superficial to deep, the meninges occur in the order
A transient increase in Na+ permeability, followed by restoration of Na+ impermeability, and then a short-lived increase in K+ permeability.
Generation of an action potential involves
ependymal cells
Glial cells of the CNS that line the central cavities of the brain and spinal cord and help circulate cerebrospinal fluid.
microglia
Glial cells of the CNS that monitor health and perform defense functions for neurons.
astrocytes
Glial cells of the CNS that regulate the chemical environment around neurons and exchange between neurons and capillaries.
oligodendrocytes
Glial cells of the CNS that wrap around neuron fibers, forming myelin sheaths.
schwann cells (neurolemmocytes)
Glial cells of the PNS that surround nerve fibers, forming the myelin sheath.
satellite cells
Glial cells of the PNS whose function is largely unknown. They are found surrounding neuron cell bodies within ganglia.
group c fibers are not capable of saltatory conduction
How are group c neuron fibers classified?
the speed with which sodium ion can be pumped back outside the neuron membrane
How fast a person can type or play the piano is ultimately limited by the number of impulses a person can send to their finger muscles per second. This in turn is limited by
31
How many pairs of mixed spinal nerves arise from the spinal cord and serve the entire body except the head and neck?
away from the cell body
In the axon, the nerve impulses travel
cerebrum and cerebellum
In the brain, the ____ and ____ have an outer gray matter layer, which is reduced to scattered gray matter nuclei in the spinal cord.
neuroglia
Nervous tissue is composed of neurons and supporting cells called
the ora serrata
Other than the optic disc, the only point where the retina is attached to the rest of the eyeball is an anterior ring called
m (hemiplegia)
Paralysis of only one side of the body
d. the cerebellum
Parkinje cells are giant multipolar neurons of a. the dorsal horn of the spinal cord b. the ventral horn of the spinal cord c. the cerebral cortex d. the cerebellum e. the reticular formation
lateral ventricle -> interventricular foramen -> third ventricle -> cerebral aqueduct -> forth ventricle -> subarachnoid space -> arachnoid villus
Pathway of CSF from the choroid plexus where it is formed to the dural sinus where it reenters the blood stream.
l ( wernicke's area)
Plan your spoken words according to learned rules of grammar
conducting region
Plasma membrane exhibits voltage-gated Na+ and K+ channels.
central nervous system
The integrating and command center of the nervous system.
b. the neurilemma and endoneurium
The regeneration tube of a peripheral nerve fiber consists of a. the axolemma and neurilemma b. the neurilemma and endoneurium c. the myelin sheath and neurilemma d. schwann cells and astrocytes e. satellite cells and oligodendrocytes
premotor cortex
The region controlling learned motor skills.
true
The repetitive muscle contractions of walking are controlled by neuronal pools in the spinal cord
Behind the retina
The result of hyperopia is an image focused
coccygeal ligament
which structure anchors the spinal cord to L2?
true
There is a layer of adipose tissue in the epidural space.
with their nerve cell bodies in the PNS and their synaptic knob in the CNS
Unipolar neurons are found
self-propagating
Unlike local potentials, actions potentials are
b. basal nuclei
Unwanted muscle contractions are inhibited by a. midbrain b. basal nuclei c. primary motor cortex d. motor association area e. premotor cortex
Sympathetic
Which division of the ANS has a more generalized effect in the body?
motor (efferent)
Which division of the peripheral nervous system carries impulses from the central nervous system to effector organs, which are muscles and glands?
sensory (or afferent)
Which division of the peripheral nervous system carries impulses toward the central nervous system from sensory receptors located throughout the body?
Myopia
Which eye disorder results in clear vision of close objects and blurry vision of distant objects?
interneurons (association neurons)
Which functional class of neuron conduct impulses between sensory and motor neurons, or in CNS integration pathways?
motor (efferent)
Which functional class of neuron conduct impulses from the CNS to effectors?
sensory (afferent)
Which functional class of neuron conduct impulses toward the CNS from receptors?
C. All sympathetic postganglionic neurons
Which of the following does NOT release acetylcholine? A. All sympathetic preganglionic neurons / B. All parasympathetic preganglionic neurons / C. All sympathetic postganglionic neurons / D. All parasympathetic postganglionic neurons
D. Blood vessels
Which of the following effectors are NOT cholinergic? A. Sweat glands / B. Heart / C. Large intestines / D. Blood vessels
C. Mammillary bodies
Which of the following is NOT a basal nucleus? A. Substantia nigra / B. Caudate nucleus / C. Mammillary bodies / D. Lentiform nucleus
B. Vascular
Which of the following is NOT a characteristic of the cornea? A. Transparent / B. Vascular / C. Refracts light / D. Allows light to enter the eye
e. nucleic acid
Which of the following is NOT a chemical class of neurotransmitters? a. acetylcholine b. amino acid c. biogenic amine d. ATP and other purines e. nucleic acid
D. innervation of skeletal muscle
Which of the following is NOT a function of the autonomic nervous system? a. innervation of smooth muscle of the digestive tract b. innervation of cardiac muscle c. innervation of glands d. innervation of skeletal muscle
alzheimer's disease
a progressive degenerative disease that ultimately leads to dementia
tinnitus
a ringing or clicking sound in the ears in the absence of auditory stimuli
diencephalon
a set of gray matter areas, and consists of the thalamus, hypothalamus, and epithalamus.
middle ear (tympanic cavity)
a small, air-filled, mucosa-lined cavity in the petrous portion of the temporal bone; spanned by the auditory ossicles
sleep
a state of partial unconsciousness from which a person can be aroused, and has two major types that alternate through its cycle.
conjunctiva
a transparent mucous membrane that lines the eyelids and the whites of the eyes
long-term memory
allows the memorization of potentially limitless amounts of information for very long periods
sacral and lumbar plexuses
also referred to as the lumbosacral plexus
lens
an avascular, biconcave, transparent, flexible structure that can change shape to allow precise focusing of light on the retina
functional brain systems
consist of neurons that are distributed throughout the brain but work together
cranial outflow
consists of preganglionic fibers that run in the oculomotor, facial, glossopharyngeal, and vagus cranial nerves
lacrimal apparatus
consists of the lacrimal gland, which secretes a dilute saline solution that cleanses and protects the eye as it moistens it, and ducts that drain excess fluid into the nasolacrimal duct
the movement of each eyeball
controlled by six extrinsic eye muscles that are innervated by the abducens and trochlear nerves
TRUE
T/F: Neurons in the CNS are organized into functional groups.
TRUE
T/F: Reflexes are rapid, automatic responses to stimuli.
the membranous labyrinth
The semicircular ducts lie within
nucleus
A ganglion is to the peripheral nervous system what a/an __ is to the central nervous system.
node of ranvier
A gap between Schwann cells in the peripheral system.
neuronal pool
A group of neurons that perform one particular function is called a/an ________
free nerve ending
A heat receptor
synapse
A junction that mediates information transfer between neurons or between a neuron and an effector cell.
reticular formation
A loosely coordinated core of gray matter in the midbrain, pons, and medulla is called the
Electroencephalogram
A record of the electrical activity of the brain is called a/an
contralateral
A reflex where the sensory input and motor output are on opposite sides of the spinal cord is called a ____ reflex arc.
false
A weak stimulus produces weaker action potentials than a strong stimulus
temporal lobes
Nerve fibers of the olfactory tracts lead to the ___.
Norepinephrine
Nerve fibers that are considered adrenergic secrete ____ as the neurotransmitter.
d. travel fastest in large myelinated fibers
Nerve signals a. travel fastest in small unmyelinated fibers b. travel fastest in large unmyelinated fibers c. travel fastest in small myelinated fibers d. travel fastest in large myelinated fibers e. travel at the same speed in all nerve fibers
One preganglionic neuron synapses with many postganglionic neurons; The secretion of epinephrine and norepinephrine can effect many organs
Why does the sympathetic division of the ANS have a more generalized effect in the body?
recent trauma with the pain sensation carried by myelinated fibers
You are experiencing pain the back, and it was significant enough to go to your physician. The physician asks you to describe not only the level of pain, usually on a 10-point rating scale, but also the type of pain-is it sharp, localize pain or dull diffuse pain. If it is a sharp, localized pain with a 8 out of 10 rating on the pain scale, you most likely have ___.
sensory projection
You are holding your hands behind your back and someone is touching a specific area of your hand. You know where your hand is touched because of ___.
stretch reflex
You begin to nod off as you are reading this question. Your head starts to lower a little but this reflex causes your head to rise.
release of endorphins and dynorphins
You feel tired, your joints hurt, and your muscles feel weak. Like any addicted exercise fanatic, your cure is to have a high intensity workout. As you are working out, all of your aches and paints seem to dwindle. This can be explained because exercise stimulates ___.
epidural space, dura mater, arachnoid, subarachnoid space
You were going to have a spinal tap to remove some cerebrospinal fluid for analysis. Starting from outside of the spinal cord, what would be the correct order of spaces and meninges through which the syringe would pass?
the dorsal horns of the spinal cord
most lower motor neurons are located in
true
t/f: a reverberating circuit produces repeated output in response to a single input.
dermatome
the area of skin innervated by the cutaneous branches of a single spinal nerve
dorsal rami
the back is innervated by the ______, with each innervating the muscle in line with the point of origin from the spinal column
volatile, and it must be dissolved in the fluid coating the olfactory epithelium that stimulates the olfactory receptors
to smell a particular odorant, it must be
midbrain, pons, medula oblongata
what 3 parts does the brain stem consist of?
soma
Nissl bodies are located in the ___ of a neuron.
trigeminal nerves (cranial nerve V)
nerves that allow sensation to the face, and motor control of chewing muscles
rod
At normal daylight intensities, the ___ cells are nonfunctional because all their rhodopsin is bleached.
rapid eye movement (REM) sleep
In sleep, when does most dreaming occur?
visceral; referred
A pain that radiates along the left shoulder and medial side of the arm may not indicate a pain specifically in that area. This may indicate a heart attack, which causes ___ pain, and the phenomenon is called ___.
voltage-gated channel
An ion channel that opens in response to a change in membrane potential and participates in the generation and conduction of action potentials.
Thoracolumbar division
Another name for the sympathetic division is the
corticospinal
Descending tracts that carry signals from the cerebral cortex for precise coordinated limb movements.
motor fibers that conduct nerve impulses from the CNS to smooth muscle, cardiac muscle and glands
Describe the ANS.
analyzes sensory information, stores information, makes decisions
Describe the integrative function of the nervous system.
converging circuit
Different types of sensory input can have the same ultimate effect.
i ( aphasia)
Difficulty producing intelligible speech due to brain injury
a. relative refractory period
During its ___ a neuron responds only to stimuli stronger than a normal threshold a. relative refractory period b. hyperpolarized phase c. period of facilitation d. synaptic delay e. absolute refractory period
serial processing
Exemplified by spinal reflexes, and involves sequential stimulation of the neurons in a circuit.
c. it is a sensory pathway
If the name of a spinal tract begins with the root spino- a. it consists of descending fibers b. it is a motor pathway c. it is a sensory pathway d its fibers do not extend beyond the spinal cord e it fibers form a spinal nerve
potassium
Immediately after an action potential has peaked, which cellular gates open?
Temporal Summation
In ___, several EPSPs occurring in quick succession depolarize a neuron to threshold.
synaptic potentiation
In ___, the additive effects of EPSPs and IPSPs determine whether a neuron fires.
synaptic vesicles; ligand-regulated gates
In a chemical synapse, the synaptic knobs of the presynaptic neuron contain ___, while the membrane of the postsynaptic neuron contains ___.
true
In a myelinated nerve fiber, action potentials occur only at the nodes of ranvier
had been damaged by infection trauma, or stroke
In an autopsy, a pathologist is found an area of brain tissue with very high concentrations of microglia. The area of the brain most likely
Ca; release ACh
In cholinergic synapse, the arrival of a nerve signal at the synaptic knob in the presynaptic neuron triggers the opening of ___ voltage-regulated, which cause
they are mostly myelin sheath made of lipid or fat molecules
In dissection, most nerve fibers appear gray to white because
Sympathetic
In general, stimulation of the posterior hypothalamus produces ____ responses.
Increase digestive functions
In general, the parasympathetic division will
contract; loosen; thickens
In looking at a near object, the ciliary muscles will ___, the suspensory ligaments ____, and the lens ____.
TRUE
T/F: Myelination of the nerve fibers in the central nervous system is the job of the oligodendrocyte.
undergo mitosis
Mature neurons lack centrioles. You would expect these neurons to be unable to
parallel after-discharge circuits
May be involved in complex activities, and are characterized by stimulation of several neurons arranged in parallel arrays by the stimulating neuron.
parallel after-discharge circuit
May be involved in complex, exacting types of metal processing.
presynaptic inhibition
May prevent a neuron from releasing it neurotransmitter
d. feelings of peace fear or anger
One of the functions associated with the limbic system is a. hearing b. reading comprehension c. stimulus filtering d. feelings of peace fear or anger e. motor control of the limbs.
oculomotor
Opening the eyes involves the ___ nerve.
b (Medulla oblongata)
Origin of the last four pairs of cranial nerves
lumbar enlargement
Nerves to the pelvic region and lower limbs arise from which area of the spinal cord?
alzheimer disease
Neurofibrillary tangles and the destruction of parts of the hippocampus are characteristic of __________
astrocytes
Neuroglia that control the chemical environment around neurons by buffering potassium and recapturing neurotransmitters.
true
Neuromodulators alter the response of a neuron to a neurotransmitter
large; myelinated
Neurons that send impulses to skeletal muscles have a ___ diameter and are
Broca's area
Nonfluent aphasia results in slow speech, difficulty in choosing words, or use of words that only approximate the correct word. Nonfluent aphasia results from a lesion to ___.
true
Not all synapses employ neurotransmitters
action potentials (nerve impulses)
Occur in axons and are the principle way neurons communicate.
propagation (transmission) of an action potential
Occurs as the local currents of an area undergoing depolarization cause depolarization of the forward adjacent area.
temporal summation
Occurs in response to several successive releases of neurotransmitter.
spatial summation
Occurs when the postsynaptic cell is stimulated at the same time by multiple terminals.
olfactory cortex; primary motor cortex
Odors like certain perfumes or certain foods stimulate a memory in the ___.
diverging circuit
One incoming fiber triggers responses in ever-increasing numbers farther and farther along the circuit.
feelings of peace, fear, or anger
One of the functions associated with the limbic system is
glycine
Principal inhibitory neurotransmitter of the spinal cord.
gracile fasciculus; medulla oblongata
Sensory information about deep touch or visceral pain in the lower limbs are carried in ___ tracts, which decussate, or cross over, in the ___.
TRUE
T/F: Large-diameter nerve fibers conduct impulses much faster than small-diameter fibers.
potential difference
The amount of difference in electrical charge between two points.
ciliary body; sclera venous sinus
The aqueous humor is secreted by the ___ and reabsorbed into the ___.
leads from the nasopharynx to the middle ear
The auditory tube ___.
the optic nerve leaves the eye
The blind spot in each visual field is a region in which
endothelium
The blood brain barrier consists of tight junctions in the
glucose, water, oxygen, and caffeine
The blood-brain barrier (BBB) is most permeable to which chemical groupings?
neurilemma
The bodies of the Schwann cells constitute the
central
The brain and spinal cord constitute the __ nervous system.
a. the limbic system
The brain center most concerned with emotion is a. the limbic system b. the reticular formation c. the basal nuclei d. the midbrain e. the thalamus
limbic system
The brain center most concerned with emotions is the
oligodendrocytes
The brain's counterpart to the Schwann cells
Lateral gray horns
The cell bodies of motor neurons to autonomic effectors are located in the
spinal cord & brain
The central nervous system consist of the _________ and _________
metencephalon
The cerebellum develops from the embryonic
mesencephalon; diencephalon
The cerebral aqueduct is located in the ___, while the third ventricle is located in the ____.
c. the temporal lobe
The cerebral cortex concerned with hearing is in a. the insula b. the occipital lobe c. the temporal lobe d. the pariental lobe e. the frontal lobe
temporal lobe
The cerebral cortex concerned with hearing is in the
gyri; increase surface area
The cerebrum and the cerebellum contain thick folds called ___ whose purpose is to ___.
telencephalon
The cerebrum develops from a vesicle of the embryonic brain called the ___
c. the radical nerve
The cervical plexus gives rise to all the following nerves except a. the great auricular nerve b. the lesser occipital nerve c. the radical nerve d. the phrenic nerve e. the ansa cericalis
resting potential; -70
The charge difference across the plasma membrane in muscles and nerve cells is called the ___ and measures about ___ millivolts.
interneuron
The connection from a sensory neuron to a motor neuron is usually made by one or more neurons called ______
interneurons
The integrative function of the nervous system is associated especially with
depolarization
The interior of the cell becomes less negative.
hyperpolarization
The interior of the cell becomes more negatively charged.
proprioceptors, which are tonic receptors
The intrafusal fibers in a skeletal muscle are ___.
synapase
The junction where one neuron meets another is called a/an _______.
thalamus
The largest part of the diencephalon is the ____, the gateway to the cerebral cortex
temporal lobe; parietal lobe
The lateral sulcus of the cerebrum separates the __ from the __.
medulla oblongata
The location of several visceral motor nuclei controlling vital functions such as cardiac and respiratory rate.
Tectorial membrane
The longest stereocilia of the outer hair cells are embedded in the
amplitude
The loudness of a sound is correlated with the ___ of the sound wave.
central canal and ventricles
The lumen of the neural tube develops into the
dura mater; dura sinuses
The outer double meningeal layer around the brain is called the ___, and in some places the two layers are separated by ___.
Cervical
The phrenic nerve is the major nerve from the ______ plexus.
true
The pons and cerebellum arise from the same vesicle of the embryonic brain
pre-central gyrus
The portion of the brain where one thinks consciously about motor activities is the ___.
true
The postscript reflex are enables a spinal output of longer duration
reflex actions and communication between the brain and spinal nerves
The primary functions of the spinal cord include
Accommodation
The process of adjusting the thickness of the lens for near vision is called
Refraction
The process of bending light rays is called
monosynaptic
The quickest reflex arcs involve only two neurons and are thus
cannot be fired again regardless of the stimulus
The refractory period represents the time period when a region of the axon
diencephalon
The retinas originate as outgrowths of the ___.
corpus callosum
The right and left cerebral hemispheres are joined mainly by the
a. corpus callosum
The right and left cerebral hemispheres are joined mainly by the a. corpus callosum b. thalamus c. pons d. decussation e. association tracts
true
The sacral segments of the spinal cord are not found within the sacral vertebrae
Sacral
The sciatic nerve comes from the _________ plexus.
endolymph
The semicircular ducts are filled with
parietal lobe
The somesthetic center of the postcentral gyrus is part of the __ of the cerebrum.
f ( VII & IX)
There would be no sense of taste if cranial nerve ___ were destroyed
nociceptors
These receptors are free nerve endings that are tonic receptors, which respond to tissue damage from trauma, ischmeia or excessive stimulation by agents such as heat, cold, and chemicals.
g protein-linked receptors
These receptors mediate indirect transmitter action resulting in slow, persistent, and often diffuse changes.
enkephalins
This chemical is released by injured tissues and is the most potent pain stimulus known.
vestibulocochlear (VIII)
This cranial nerve controls hearing and equilibrium
Amyotrophic lateral sclerosis
This disease is marked by degeneration of motor neurons, and in most cases, neurons are destroyed by the inability of astrocytes to reabsorb glutamate, which allows this neurotransmitter to reach toxic levels.
spina bifida
This is a congenital defect resulting from the failure of one or more vertebrae to form a complete vertebral arch for enclosure of the spinal cord.
dura mater
This meninx lies closest to the surrounding bone.
vermis
This narrow structure connects the cerebellar hemispheres
sciatic
This thick nerve of the lower limb is actually two nerves enclosed in a common fibrous sheath.
sensory; shingles
This virus remains for life in the dorsal root ganglion but can travel down neurons from the dorsal root ganglion by fast axonal transport and cause a painful trail of skin discoloration along the path of the neurons. This virus travels down ___ neurons and causes ____.
Trigeminal
Tic douloureux is caused by a lesion to the ____________ nerve.
parallel processing
When information is delivered within the CNS simultaneously by different parts of the neural pathway.
sodium ions diffuse into the outer segment
When light is absorbed by a rod cell ___.
temporal
When one or more presynaptic neurons fire in rapid order it produces a much greater depolarization of the postsynaptic membrane than would result from a single EPSP; this event is called ___ summation.
tympanic membrane
When the stapes pushes in an creates pressure on the endolymph, the __ bulges out to relieve the pressure.
accommodation
When you view objects close to the eye, the eye makes an adjustment called ___.
Arachnoid granulations into the dural sinuses
Where does cerebrospinal fluid return to the blood supply?
threshold
Whether or not a neuron fires depends on whether it is depolarized to a voltage called its
Eyebrows
Which accessory structure of the eyes protect the eyes by preventing perspiration from getting into the eyes?
axons with larger diameters
Which axons conduct impulses faster: axons with larger diameters, or axons with smaller diameters?
unmyelinated axons
Which axons conduct impulses relatively slowly?
myelinated axons
Which axons have a high conduction velocity?
Scala vestibuli
Which cochlear chamber is connected to the oval window into the middle ear?
Wernicke's area
Which cortical area is necessary for understanding and formulating coherent speech?
A. Trigeminal
Which cranial nerve is NOT involved with taste? A. Trigeminal / B. Glossopharyngeal / C. Vagus / D. Facial
Facial
Which cranial nerve is the major motor nerve for facial expressions?
Trigeminal
Which cranial nerve is the major sensory nerve from the face?
Vagus
Which cranial nerve leaves the head and neck region to supply the internal viscera?
vestibulocochlear
Which cranial nerves carries equilibrium messages?
Reticulospinal
Which descending tract carries impulses for posture adjustment and walking?
somatic nervous system
Which nervous system allows conscious control of motor activities?
somatic nervous system
Which nervous system consists of somatic nerve fibers that conduct impulses from the CNS to skeletal muscles?
E. provide the defense for the CNS
Which of the following is NOT a function of astrocytes? A. support and brace neurons B. anchor neurons to blood vessels C. guide the migration of young neurons, synapse formation, and helping to determine capillary permeability D. control the chemical environment around neurons E. provide the defense for the CNS
C. Origin of impulses to skeletal muscle
Which of the following is NOT a function of the cerebellum? A. Controls balance and eye movements / B. Controls posture, locomotion and fine motor coordination / C. Origin of impulses to skeletal muscle / D. Planning, practicing and learning complex movements
D. All of the choices are correct
Which of the following is NOT a function of the hypothalamus? A. Body temperature control / B. Autonomic nervous system control / C. Mood and emotions / D. All of the choices are correct
B. Auditory relay center
Which of the following is NOT a function of the medulla oblongata? A. Regulate heart rate / B. Auditory relay center / C. Regulate blood vessel diameter /D. Regulate breathing
D. Visual relay center
Which of the following is NOT a function of the pons? A. Controls chewing and salivation / B. Aides the medulla oblongata in controlling breathing, swallowing and balance / C. Relay between the cerebellum and cerebrum / D. Visual relay center
glycine
an inhibitory neurotransmitter
olfactory transduction
an odorant binds to the olfactory receptor, a g protein, and the secondary messenger of cyclic AMP.
cut or compressed axons can regenerate
if damage to a neuron occurs to the axon and the cell body remains in tact
phrenic nerves
if the ___ of the cervical plexus were severed, it would have a life-threatening effect.
epithalamus
includes the pineal gland, which secretes melatonin and regulates the sleep-wake cycle.
somatosensory association cortex
integrates sensory information and produces an understanding of the stimulus being felt.
limbic system
involved with emotions, and is extensively connected throughout the brain, allowing it to integrate and respond to a wide variety of environmental stimuli.
prefrontal cortex
involved with intellect, cognition, recall, and personality, and is closely linked to the limbic system.
