A&P Nervous System
You can realize that a structure belongs to the diencephalon because "____" is part of its name.
"-thalamus".
Functions of the Nervous System
-Collect information via receptors and stimuli -Process and evaluate information -Initiate response to information via effectors
Name some of the components of the BBB.
-Continuous basement membrane -Tight junctions -Perivascular feet
Name the functions of the Hypothalamus.
-Control of autonomic nervous system -Control of the endocrine system -Control of emotional behavior -Control of food and water intake -Regulation of sleep-wake rhythms
These nuclei are located in the lateral horns and innervate smooth muscle, cardiac muscle, and glands.
Autonomic motor nuclei
Conducts action potentials away from the cell body of a neuron
Axon
The posterior horns of the spinal cord contain...
Axons of sensory neurons and cell bodies of interneurons.
Location where action potentials are generated by a neuron, the part of a neuron distinguished by its notable absence of chromophilic substance
Axon hillock
True or False There are no voltage-gated channels in myelin sheaths.
True The voltage-gated channels are found in the neurofibril nodes.
True or False The Cerebrum is composed of both white and gray matter.
True
True or False The spinocerebellar pathway is an ascending somatosensory pathway.
True
What is a neurotransmitter?
A neurotransmitter is a small organic compound released in the synaptic cleft.
What structures are located within the lateral horns?
-Cell bodies of visceral motor neurons -Axons that extend to visceral effectors
Name two places in the brain where gray matter is found.
-Cerebral nuclei -Cerebral cortex
Name the four major regions of the brain.
-Cerebrum -Diencephalon -Brainstem -Cerebellum
Chemically gated ion channels are mainly found in the ________ segment of a neuron.
Receptive
Protects and regulates nutrient and waste exchange for cell bodies in peripheral nerve ganglia
Satellite cell
Name the three functions of the cerebrospinal fluid (CSF).
-Buoyancy -Protection -Environmental stability
Name the four groups of neurotransmitters.
-Acetylcholine -Amino acids -Monoamines -Neuropeptides
List all of the brain structures that are composed of white matter.
-Corpus callosum, Septum pellucidum, Internal capsule
Name two ways in which neurotransmitters are removed from the synaptic cleft.
-Degradation -Reuptake
Name two factors that influence the velocity of a nerve signal.
-Diameter of the axon -Myelination of the axon
Characteristics of Neurons
-Excitability -Conductivity -Secretion -Extreme longevity -Amitotic
Name the four dural cranial septa.
-Falx Cerebri -Tentorium Cerebelli -Falx Cerebelli -Diaphragma Sellae
Name the five cerebral lobes.
-Frontal lobe -Parietal lobe -Temporal lobe -Occipital lobe -Insula
Name the three parts of the brainstem.
-Midbrain -Pons -Medulla Oblongata
Give two reasons why gray matter is gray.
-No axons, therefore no myelination -Presence of chromatophilic substance
Match the cranial nerve number with its name. -Cranial nerve I -Cranial nerve II -Cranial nerve III -Cranial nerve IV -Cranial nerve V -Cranial nerve VI -Cranial nerve VII -Cranial nerve VIII -Cranial nerve IX -Cranial nerve X -Cranial nerve XI -Cranial nerve XII
-Olfactory -Optic -Oculomotor -Trochlear -Trigeminal -Abducens -Facial -Vestibulocochlear -Glossopharyngeal -Vagus -Accessory -Hypoglossal
Put the cranial meninges in order, from deep (closest to the brain) to superficial (farthest from the brain).
-Pia mater -Arachnoid mater -Dura mater
Name the three primary brain vesicles.
-Prosencephalon (Forebrain) -Mesencephalon (Midbrain) -Rhombencephalon (Hindbrain)
List the functions of the Hypothalamus.
-Regulates hunger and thirst -Regulates the autonomic nervous system -Regulates circadian rhythms -Regulates body temperature
List the functions of the Thalamus.
-Relay center for sensory input -Arousal from sleep
Name the five secondary brain vesicles.
-Telencephalon -Diencephalon -Mesencephalon -Metencephalon -Myelencephalon
Which of the following are prevented from entering the interstitial fluid of the brain, due to the blood-brain barrier? -Waste products in the blood -Some hormones -Alcohol -Nicotine
-Waste products in the blood -Some hormones
Match the disorder listed with the cranial nerve associated with that disorder. -tongue deviates to one side when it is stuck out of the mouth -soft palate droops on one side (2 answers but choose vagus) -weakness in elevation of the scapulae -inability to smell -pupillary reflexes are absent -inability to taste bitter (sensed by posterior taste buds of the tongue) -glossopharyngeal -inability to pucker the lips -blindness -inability to laterally rotate the eye -corneal reflex is absent -difficulty turning the eye inferior and lateral -inability to maintain balance and equilibrium
-hypoglossal -vagus -accessory -olfactory -oculomotor -glossopharyngeal -facial -optic -trochlear -trigeminal -abducens -vestibulocochlear
A neuron conducting an impulse from the CNS to the detrusor muscle of the urinary bladder would be classified as a(n) __________ neuron.
Autonomic motor
Which occurs first? Absolute or Relative refractory period?
Absolute refractory period
Which type of signal has the ability to travel a great distance without losing its strength?
Action Potential
Involved in emotions, behavioral activities, and moods
Amygdaloid body
Participates in expression of emotion, control of behavioral activities, and moods.
Amygdaloid body (Amygdala)
The groove that extends the length of the spinal cord on its anterior surface is the ____.
Anterior median fissure
Information coming from the spinal cord and PNS, going to the brain
Ascending sensory
-Communication between adjacent gyri -Communication within hemisphere
Association tract
-Helps form the blood brain barrier (BBB) -Regulates tissue fluid composition -Provides structural support and organization to the CNS -Assists with neuronal development -Replicates to occupy space of dying neurons
Astrocyte
Where are synaptic knobs located?
At the tips of the telodendria
Protects nervous tissue by strictly regulating which substances can and cannot enter the ISF of the brain
Blood-brain barrier (BBB)
Sensory pathways terminate in the _____, and motor pathways terminate at the _____.
Brain, effectors
How are neurotransmitters classified?
By chemical structure
What is the correct order for the parts of the spinal cord, from superior to inferior?
Cervical - thoracic - lumbar - sacral - coccygeal
Identify the structure(s) that are innervated by visceral motor neurons.
Cardiac muscle tissue, smooth muscle tissue, glands
The structure that consists of dorsal and ventral roots within the lumbar region of the vertebral canal and the sacral canal (extending from the inferior end of the spinal cord) is the ____.
Cauda equina
"Toward the tail"- synonymous with posterior.
Caudal
Helps produce pattern and rhythm of walking movement.
Caudate nucleus
Stimulate muscles to produce the pattern and rhythm of walking
Caudate nucleus
There are two types of synapses, based on mode of communication. What are they?
Chemical and Electrical
True or False A sulcus is a fold of brain tissue, and a gyrus is a groove between folds of brain tissue.
False. A gyrus is a fold of brain tissue, and a sulcus is a groove between folds of brain tissue.
Sickle-shaped vertical partition that divides left and right cerebellar hemispheres, contains the occipital sinus.
Falx Cerebelli
As motor tracts descend to the brainstem they become the anterolateral surfaces of the midbrain known as the ____.
Cerebral peduncles
Location of all conscious thought processes and origin of all complex intellectual function
Cerebrum
The enlargement associated with the upper limb is the ____ enlargement.
Cervical
The spinal cord part with the largest diameter is the ______ part.
Cervical
The lateral horns of the spinal cord contain...
Cell bodies of autonomic motor neurons.
Contains the nucleus and cellular organelles
Cell body
Includes the brain, spinal cord, and interneurons
Central Nervous System (CNS)
A groove between the frontal lobe and the remaining lobes
Central sulcus
Which part of the brain contains the arbor vitae?
Cerebellum
Name the channel located between the third and fourth ventricle.
Cerebral aqueduct
External sheets of gray matter that cover the surface of the cerebrum
Cerebral cortex
What is the most important part of your brain?
Cerebral cortex
Internal clusters of gray matter within the white matter
Cerebral nuclei
Connects the midbrain to the cerebrum
Cerebral peduncle
CSF is produced here.
Choroid plexus
Dark-staining rough ER found in the cell body that produces membrane-associated proteins
Chromatophilic substance
Processes visual information at a subconsious level
Claustrum
The inferior tip of the spinal cord is the _______ part.
Coccygeal
-Communication between hemispheres -Anterior commisure -Corpus callosum
Commissural tract
This segment is equivalent to the length of the axon and its branches called telodendria, contains voltage-gated K+ and Na+ channels.
Conductive segment
Since most pathways decussate, each side of the brain processes information from the _________ side of the body.
Contralateral
When the brain senses and controls the opposite side of the body, it is called ____.
Contralateral
The tapered, conical inferior end of the spinal cord is called the
Conus medullaris
A fiber tract that connects the right and left cerebral hemispheres
Corpus Callosum
Vertical sickle-shaped fold located on midsagittal plane and projects into longitudinal fissure between left and right cerebral hemispheres
Falx Cerebri
The multiple branching processes of a neuron
Dendrite
The dura mater is composed of _____ connective tissue
Dense irregular
Information going from the brain to the spinal cord and PNS
Descending motor
Attaches pituitary gland to the base of the Hypothalamus
Diaphragma Sellae
Derives from the prosencephalon and eventually forms the Thalamus, Hypothalamus, and Epithalamus
Diencephalon
Areas where the meningeal and periosteal layers separate to form large blood-filled spaces.
Dural venous sinuses
When a neurotransmitter opens a chemically gated ion channel that allows sodium to enter the postsynaptic cell, the result is an ____.
EPSP
Which statement accurately describes spinal nerves?
Each spinal nerve is mixed in that it contains some sensory axons and some motor axons.
The nervous system controls the activity of muscles and glands. Muscles and glands can generate changes and are therefore called ____.
Effectors
Of the two types of synapses, based on mode of communication, which is less common but allows faster signal transmission?
Electrical synapse
What is the thin strand of pia mater that helps to anchor the spinal cord to the coccyx?
Filum terminale
Surrounds an individual axon
Endoneurium
-Lines ventricles of brain and central canal of spinal cord -Assists in production of cerebrospinal fluid (CSF)
Ependymal cell
Which space associated with the spinal cord meninges contains areolar connective tissue, blood vessels, and adipose connective tissue?
Epidural space
Surrounds the entire nerve
Epineurium
When the brain senses and controls the same side of the body, it is called ____.
Epsilateral
Temporary less negative state due to depolarization (increase of Na+)
Excitatory Postsynaptic Potential (EPSP)
The function of upper motor neurons is to...
Excite or inhibit motor portions of the cerebral cortex.
True or False Axons of the anterior corticospinal tracts decussate in the medulla.
False
True or False Motor pathways are also called ascending pathways.
False
True or False Conduction speed is faster for motor neurons than for sensory neurons.
False Conduction is much faster for sensory neurons than for motor neurons.
True or False Astrocytes allow proteins to leak out of the capillaries into the nervous tissue.
False Some proteins are considered neurotransmitters so the astrocytes do not let proteins leak out, it must be processed first.
True or False A cranial nerve originates from the brain and is part of the central nervous system.
False The central nervous system contains the brain and the spinal cord. A cranial nerve originates from the brain, yet it is part of the peripheral nervous system.
True or False It is okay for plasma to leak out of the capillaries into nervous tissue.
False The components in plasma such as protein and potassium will affect neurons. The BBB keeps capillaries from leaking around neurons.
True or False Myelinated axons and unmyelinated axons have the same conduction speed.
False Unmyelinated axons have slower conductions.
Deeper grooves in the brain
Fissures
What term describes the folds on the cerebellum?
Folia
Name the ventricle located between the brainstem and cerebellum.
Fourth ventricle
Primarily concerned with voluntary motor functions, concentration, verbal communications, decision making, planning, and personality
Frontal lobe
A collection of cell bodies in the PNS
Ganglion
Excites and inhibits the thalamus to adjust muscle tone
Globus pallidus
Occurs in the receptive segment of a neuron and are due to the opening of chemically-gated channels, includes IPSP's and EPSP's.
Graded (Local) potentials
The inner medulla of the spinal cord consits of ____ matter.
Gray
Derives color from motor neuron and interneuron cell bodies and their associated capillary beds, as well as the neuronal dendrites and some unmyelinated axons
Gray Matter
This structure contains unmyelinated axons and serves as a communication route between the right and left sides of the gray matter in the spinal cord.
Gray commissure
Dendrites, cell bodies, and unmyelinated axons are examples of ____.
Gray matter
Folds in the adult brain
Gyrus (pl. gyri)
Which of the following is not characteristic of neurons? -High mitotic rate -High metabolic rate -Require continuous supplies of glucose and oxygen -Extreme longevity -No exceptions; all of these are characteristic of neurons
High mitotic rate
When a neurotransmitter causes the opening of chemically gated potassium channels on the postsynaptic cell, the postsynaptic potential that results is an ____.
IPSP, which is a hyperpolarization.
Cerebrospinal fluid enters the third ventricle of the brain by way of the ____.
Interventricular foramina
Connects medulla oblongata to cerebellum
Inferior cerebellar peduncle
Temporary more negative state due to decrease of K+ or increase of Cl-
Inhibitory Postsynaptic Potential (IPSP)
This segment is composed of the axon hillock, contains voltage-gated K+ and Na+ channels.
Initial segment
Involved in memory and interpretation of taste, lack of access to this region
Insula
A neuron that does not start at a receptor or end at an effector, the most common type of neuron.
Interneuron
The neurons that are responsible for integrating information by retrieving, processing, storing, and "deciding" how the body responds to stimuli are ____.
Interneurons
The posterior gray horn contains the cell bodies of ____.
Interneurons
A hole between the lateral ventricle and the third ventricle
Interventricular foramen
Where can the BBB (blood-brain barrier) be found?
It can't. The BBB does not actually exist, it is simply a concept.
The inferior end of the spinal cord lies at what vertebral level in the adult?
L1
A groove between the temporal and parietal lobes
Lateral sulcus
Name the two most superior ventricles.
Lateral ventricles
The ventricle(s) of the brain that is/are located within the cerebral hemispheres is/are the ____.
Lateral ventricles
Between external insula and lateral diencephalon, composed of putamen and globus pallidus.
Lentiform nucleus
Brain structures such as the mammillary bodies, which are involved with the suckling reflex and emotions, are part of the ____ system.
Limbic
A groove between the right and left cerebral hemispheres
Longitudinal fissure
The neurons that directly innervate skeletal muscles are called ____.
Lower motor neurons
The enlargement associated with the lower limb is the ____ enlargement.
Lumbar
Only primary brain vesicle that does not form a new secondary vesicle, becomes the midbrain
Mesencephalon
Arises from the rhombencephalon and eventually forms the pons and cerebellum
Metencephalon
-Least common type of glial cell -Defends against infectious agents and engulfs debris from dead or dying neurons -Engage in phagocytosis in response to tissue injury
Microglial cell
Glial cells in the CNS derived from circulating monocytes, engage in phagocytosis in response to tissue injury.
Microglial cells
Place the three parts of the brainstem in order from most superior to most inferior.
Midbrain, Pons, Medulla Oblongata.
Connects pons to cerebellum
Middle cerebellar peduncle
The direct motor pathway originates in the...
Motor cortex of the cerebral cortex.
A neuron that ends at an effector
Motor neuron
Also known as a descending tract.
Motor tract
Also derives from the rhombencephalon, eventually forms the Medulla Oblongata
Myelencephalon
A bundle of myelinated axons in the PNS
Nerve
The Hypothalamus is the connection between the ____ system and the ____system.
Nervous system, Endocrine system.
Node of Ranvier, in between myelin sheath, bare region on a myelinated axon where action potentials are propagated
Neurofibril node
-Myelinates and insulates PNS axons -Allows for faster action potantial conduction along an axon in the PNS -Counterpart of oligodendrocyte in CNS
Neurolemmocyte
Can you have a neuron that is both sensory and motor?
No.
A collection of cell bodies in the CNS
Nuclei
Lumps of gray matter buried within white matter, located in all four regions of the brain are called ____.
Nuclei
Responsible for processing incoming visual information and storing visual memories
Occipital lobe
-Myelinates and insulates CNS axons -Allows faster action potential conduction along axons in the CNS -Counterpart of neurolemmocyte in PNS
Oligodendrocyte
Involved with general sensory functions such as evaluating the shape and texture of objects being touched
Parietal lobe
A structure that holds up something else
Peduncle
Surrounds a fascicle of axons
Perineurium
Carries signals to skeletal muscles, sympathetic and parasympathetic division.
Peripheral Nervous System- Motor (PNS)
Includes ganglia and nerves, responds to the environmental conditions. (pain receptors in hand)
Peripheral Nervous System- Sensory (PNS)
Cerebrospinal fluid circulates between the ____ mater and the ____ mater.
Pia, Arachnoid
The groove that extends the length of the spinal cord on its posterior surface is the ____.
Posterior median sulcus
The cell bodies of sensory neurons are located in the...
Posterior root ganglion
Which structure is closest to the spinal cord?
Posterior rootlets
Area of the brain that determines which responses are appropriate.
Prefrontal cortex
Located within the temporal lobe, where it receives and processes auditory information
Primary auditory cortex
Located in the insula and is involved in processing taste information
Primary gustatory cortex
Located within the temporal lobe, provides conscious awareness of smells
Primary olfactory cortex
Located within the occipital lobe, where it receives and processes incoming visual information
Primary visual cortex
-Communication between higher and lower brain regions -Corticospinal tracts
Projection tract
What is the only brain signal that does not cross over?
Proprioceptors to the cerebellum are ipsilateral.
Controls muscular movement at the subconscious level
Putamen
This segment includes dendrites and the cell body, which are regions of the neuron that receive stimuli to excite the neuron, contains chemically-gated channels (K+, Cl-) but little to no voltage-gated channels.
Receptive segment
Regulates state of consciousness
Reticular activating system (RAS)
Projects vertically through the core of the midbrain, pons, and medulla oblongata. Connected with states of consciousness.
Reticular formation
"Toward the nose"- synonymous with anterior.
Rostral
A conduction that jumps from node to node is called ____.
Saltatory conduction
The axons of primary sensory neurons make synaptic connections with...
Secondary neurons in the CNS.
The afferent division of the nervous system is also known as the _____ division.
Sensory
The cell bodies of ____ neurons are located in the posterior root ganglion.
Sensory
A mixed nerve refers to one that contains both ____.
Sensory and motor neurons
Motor output to skeletal muscle
Sensory motor
A neuron that starts at a receptor
Sensory neuron
Also known as an ascending tract.
Sensory tract
Name the membrane that separates the two lateral ventricles.
Septum Pellucidum
What divides the lateral ventricles?
Septum pellucidum
Identify the structure(s) that are innervated by somatic motor neurons.
Skeletal muscle tissue
True or False An individual tract within the spinal cord contains either sensory nerve signals or motor nerve signals only.
True
The _______ nuclei within the gray matter of the spinal cord send nerve impulses to skeletal muscles.
Somatic motor
The anterior gray horn contains the cell bodies of the ____ neurons.
Somatic motor
The portion of the nervous system that has voluntary control over skeletal muscles is the _____________ division.
Somatic motor
Nuclei within the gray matter of the spinal cord that receive information from sensory receptors such as pain or pressure receptors in the skin are _____ nuclei.
Somatic sensory
Sensation from cutaneous touch, pain, temperature, position, and pressure receptors
Somatic sensory
Occurs when multiple presynaptic neurons release neurotransmitter at various locations onto the receptive segment, generating EPSP's, IPSP's or both.
Spatial summation
Somatic sensation from special sensory organs such as the eye and ear
Special sensory
True or False Cranial nerves are part of the PNS.
True
True or False Dural venous sinuses carry blood and cerebrospinal fluid (CSF).
True
In a lumbar puncture (spinal tap), fluid is extracted from the ____.
Subarachnoid space
Which space associated with the spinal cord meninges contains cerebrospinal fluid?
Subarachnoid space
Shallow depressions of the brain
Sulcus (pl. sulci)
Connects midbrain to cerebellum
Superior cerebellar peduncle
Swelling on the ends of an axon
Synaptic knob
Arises from the prosencephalon and eventually forms the cerebrum
Telencephalon
The branches at the end of axons
Telodendria
Involved with hearing and smell
Temporal lobe
Occurs when a single presynaptic neuron releases excitatory neurotransmittor to stimulate the postsynaptic neuron at the same location repeatedly in a very short period of time.
Temporal summation
True or False The subdural space is the region between the arachnoid mater and the dura mater.
True
Horizontally oriented fold of dura mater that separates the occipital and temporal lobes of the cerebrum from the cerebellum. Forms a "tent" over the cerebellum.
Tentorium Cerebelli
Neurons of the thalamus that are part of sensory conduction pathways are considered _____ neurons.
Tertiary
True or False Neurons in the primary somatosensory cortex receive input from tertiary neurons that have their cell bodies residing in the thalamus.
True
True or False A fasciculus is smaller than a funiculus.
True
Where would you find the autonomic sensory nervous system?
There is no autonomic sensory nervous system.
What two things does the cerebral aqueduct connect?
Third and fourth ventricles
Name the ventricle surrounded by the diencephalon.
Third ventricle
Which region(s) of the spinal cord contain lateral horns?
Thoracic
A bundle of myelinated axons in the CNS
Tract
Which statement accurately compares the transmission speed of the different types of synapses?
Transmission at chemical synapses involves a brief synaptic delay, but electrical synapses are faster.
This segment includes the synaptic knobs, contains voltage-gated Ca2+ pumps.
Transmissive segment
A groove that separates the cerebrum from the cerebellum
Transverse fissure
A fluid-filled space, filled with CSF.
Ventricle
What structure lies along the midline of the cerebellum?
Vermis
Motor output to cardiac muscle, smooth muscle, and glands
Visceral motor
A neuron conducting an impulse from the stomach wall to the CNS would be classified as a(n) __________ neuron.
Visceral sensory
Sensation from sensory receptors within visceral organs
Visceral sensory
The majority of the cerebrum consists of ____ matter.
White
The outer cortex of the spinal cord consists of ____ matter.
White
Derives color from the myelin on the abundant myelinated axons
White Matter
Myelinated axons and fiber tracts are examples of ____.
White matter
If you see a tract, will it be white or gray matter? Why?
White matter, because it contains myelin.
Is there any sensory information that bypasses the Thalamus and goes directly into the brain?
Yes, smell.
Can you have a nerve that is both sensory and motor?
Yes.
If your cerebellum is damaged, what happens as a result?
Your brain is still functional, but uncoordinated. Motion and movement appears very unbalanced, and speech is impaired and uncoordinated.
Glial cells differ from neurons in that they ____.
are smaller and capable of mitosis.
The conductive segment of a neuron is its _______, a region that contains many _______ gated channels.
axon, voltage
When a nerve impulse reaches the transmissive segment of a neuron _____.
calcium diffuses into the neuron and neurotransmitter is released by exocytosis.
Motor pathways are _________ tracts that control _________.
descending, effectors
Hyperpolarization of a neuron results from ____.
either the entry of an anion or the exit of a cation.
In a typical excitable cell, the concentration of Na+ in the ECF is ______ the concentration of Na+ in the ICF.
greater than
The reticular formation is an area of the brain that...
has both sensory and motor components.
In a typical excitable cell, the concentration of K+ in the extracellular fluid is ______ the concentration if K+ in the intracellular fluid.
less than
The lateral corticospinal tracts include a ________ of the upper motor neuron axons that pass through the medulla, and they govern control of ___________.
majority, muscles used for finely controlled movements
Saltatory conduction occurs in ____.
myelinated axons, where action potentials occur only at neurofibril nodes.
In a myelinated axon, the greatest concentration of voltage-gated ion channels is in the ____.
neurofibril nodes
The counterpart of a neurolemmocyte (Schwann cell) in the CNS is an ______?
oligodendrocyte
Arrival of an action potential at the synaptic knob results in ____.
opening of voltage-gated calcium channels and diffusion of calcium into the synaptic knob.
In neurophysiology, the term summation refers to the addition of ____.
postsynaptic potentials at the initial segment.
The function of myelin is to ____.
produce faster nerve impulse propagation.
A posterior root contains...
sensory axons only.
A graded potential is one that ____.
varies in size depending on the magnitude of the stimulus (larger voltage change for stronger stimulus).
Action potentials are generated by the opening of ________ gated channels and they occur on the ________.
voltage, axon