Unit 4 Anatomy & Physiology
Terms in this set (222)
Fast retrograde transport returns used synaptic vesicles and other materials to the soma and informs the soma of conditions at the axon terminals.
movement up the axon away from the soma
movement of enzymes and cytoskeletal components down the axon to renew worn-out axoplasmic components
slow anterograde transport
returns used synaptic vesicles and other materials to the soma
fast retrograde transport
movement of enzymes and small molecules toward the distal end of the axon
fast anterograde transport
two-way passage of proteins, organelles, and other materials along an axon
In the PNS, unmyelinated fibers are enveloped in Schwann cells.
Individual EPSPs and IPSPs determine whether or not a neuron fires, and the rate of firing, by stimulating or inhibiting the production of more action potentials.
The Schwann cell's plasma membrane spirals repeatedly around the unmyelinated fiber as it does in a myelin sheath.
place the following in the order that an electrical impulse would travel beginning with the post-synaptic membrane
3. axon hillock
5. node of rangier
6. terminal aborization
7. synaptic knobs
a damaged ____ nerve fiber may regenerate if its soma is intact and some neurilemma remains
when a nerve fiber is cut the fiber distal to the injury ____ survive
near the site of injury, the basal lamina and the neurilemma form a ______ tube
the tube guides the growing sprout back to the original target cells reestablishing ______ contact
when contact is established, the ____ shrinks and reinnervated muscle fibers regrow
Choose the incorrect statement regarding how the nervous system coordinates homeostasis in the body.
The spinal cord and brain process information without regard to past experiences, and determine what response, if any, is appropriate to the circumstances.
Choose the correct statement about myelin.
It is best not to give children under two years of age a low-fat diet because myelin formation requires lipids.
basic life support (breathing regulation)
gamete (sex cell) production
Encoding stimulus strength depends on which of the following? Check all that apply.
-Different neurons have different thresholds of excitation
-The more strongly a neuron is stimulated, the more frequently it fires
form the myelin sheath in the CNS
ciliated cells resembling epithelium
produce and circulate CSF
macrophages of the CNS
most abundant CNS glial cells
multi-functioning cells involved with neurogenesis, scar formation, etc.
form the myelin sheath in the PNS
insulate neurons and enhance the rate of transmission in the PNS
surround and insulate cells of the PNS and found around the somas
What is(are) the fundamental physiological properties that enable nerve cells to communicate with other cells?
The ability to respond to environmental changes, the ability to produce electrical signals that are quickly conducted to other cells at distant locations, and the ability to secrete a chemical that will stimulate the next cell when an electrical signal reaches the end of a nerve fiber
What is the most important mechanism for transmitting qualitative information?
the labeled line code
Nerve cells have the same three fundamental physiological properties as muscle cells do: excitability, conductivity, and secretion.
Select the accurate statement(s) regarding the divisions of the nervous system. Choose all that apply.
-The sympathetic division tends to arouse the body for action
-The parasympathetic division tends to have a calming effect.
Which of the following cause a postsynaptic transmission to stop? Check all that apply.
-Diffusion of the neurotransmitter into the nearby extra-cellular fluid
-Reuptake of the neurotransmitter by endocytosis
-Degradation of the neurotransmitter in the synaptic cleft
Which of the following is true of interneurons?
They are contained entirely within the CNS and carry signals from one neuron to another.
The resting membrane potential is negative due to which of the following?
There are more negatively charged particles on the inside of the membrane than on the outside
Place the following statements in the correct order for an action potential to be generated.
1. a neuron starts at its resting membrane potential
2. excitatory postsynaptic potentials (EPSP's) are received
3. Na+ flows into the cell making the inside more positive
4. the cell reaches threshold
5. voltage-gated Na+ channels open
6. An action potential is generated
Place the following labels in the proper position to designate action potential or local potential.
-voltage regulated sodium channels
-voltage regulated potassium channels
-rate of transmission is increased with myelination
-important for transmission over long distance
-ligand regulated sodium channels
-sodium potassium ATPase pumps work to re-establish RMP
resting membrane potential is created as a result of a greater net flow of positive charges from the
ICF to the ECF
though potassium and sodium both leak through the membrane at rest, there is a greater diffusional flow of _____ at rest
the diffusional movement of sodium and potassium across the membrane is driven at all times by the
the electrical and chemical gradients for _____ are both high during resting membrane potential which results in a very high electrochemical gradient towards the inside of the cell
in order to maintain the electrochemical gradients for sodium and potassium, ATPase pumps move these ions _____ their respective gradients
What are the three general classes of neurons that correspond to the three major aspects of nervous system function? Check all that apply.
-Motor neurons that send signals predominantly to muscle and gland cells
-interneurons that lie between, and interconnect the incoming sensory pathways and the outgoing motor pathways of the CNS
-Sensory neurons that are specialized to detect stimuli such as light, heat, pressure, and chemicals, and transmit information about them to the CNS
Why is myelin important? Check all that apply.
-It speeds up signal conduction in the nerve fiber.
-It is formed to assist in the regeneration of damaged fibers.
-It insulates the nerve fiber.
an unmyelinated fiber has voltage gated ion gates along its entire
an action potential at the ______ zone causes sodium to diffuse into the cell
this results in membrane
the depolarization causes a _____ that excites the entire membrane
this continues until the traveling signal reaches the end of the
Which of the following is not a way that receptors are classified?
by sensory projection
Taste signals travel from the tongue through the facial and glossopharyngeal nerves.
Olfaction results from the stimulation of chemoreceptors.
Where do most second-order somesthetic neurons synapse with third-order neurons?
The middle ear consists of a fluid-filled chamber.
Most somesthetic signals in the right side of the body reach the cerebral cortex in the contralateral primary somesthetic area.
What is the only sense in which signals can reach the cerebral cortex without passing first through the thalamus?
Transduction begins with an action potential in a sensory receptor.
Nerve fibers from all regions of the retina converge on the __________ and exit the eye by way of the optic nerve.
The vestibule contains organs of hearing and equilibrium.
You can smell the fragrance of your deodorant when you just put it on, but after a little while the smell fades. What explains this phenomenon?
The phasic nature of the sense of smell
Changes in cerebrospinal fluid pH are detected by __________.
Which of the following structures belong to the inner ear?
The spinal cord achieves the function of locomotion through __________.
groups of neurons called central pattern generators
Reflexes have four important properties: they require stimulation, they are quick, they are involuntary, and they are stereotyped.
Which of the following is/are a component of all spinal reflex arcs? Check all that apply.
the reflex that results in quick contraction of the same muscle stimulated is called the _____ reflex
a reflex hammer striking the tendon is the _____ that triggers the _____
the afferent neuron synapses with the ____ in the integrating center
this makes it a(n) _____ reflex arc
if we are using the patellar ligament as the example, the quadriceps muscles are the _____
the antagonist will be inhibited. this is an exampled of ______
Which of the following statements describes a way that reflexes differ from other motor actions? Check all that apply.
-Reflexes can occur even if the spinal cord has been severed
-Reflexes occur without intent and are difficult to suppress.
-Reflexes generally involve few or no interneurons.
the reflex that results in one quickly removing the hand from a hot stove is the _____ reflex
the hot stove is the ____ that triggers the ____
the afferent neuron synapses with a(n) ____ , which then synapses with the efferent neuron
this makes it a(n) _____ reflex arc
if the elbow flexors remove ones hand from the stimulus, those muscles are the
the elbow extensors are inhibited to allow the response. these muscles are the
Which of the following statements is true regarding dermatomes?
Dermatomes overlap at their edges by as much as 50%.
Which portion of a reflex arc is most likely to be located entirely within the central nervous system?
The spinal cord serves four principle functions: conduction, neural integration, locomotion and reflexes.
-marked by low myelination
-somas, synapses, and dendrites
-integrates arriving electrical signals
-functions include integration of electrical input and generation of action potentials
-contains myelinated axons
-located to the periphery of the spinal chord
-transmits electrical signals rapidly over long distances
-medial vestibulospinal tract
-anterior spinocerebellar tract
-functions include transmission of electrical impulses from one point to another
a feather is rubbed over a section of skin on the palm of the hand, eliciting an action potential that was generated from neurons associated with
action potentials traveling in the posterior root reach the synapse with second order neurons located in the ______ of the spinal chord
the transfer of electrical signals between first and second order neurons occurs
prior to decussation
second order neurons ascend the spinal chord in the
arriving on the _____ side of the thalamus, action potentials are transferred to third order neurons
third order neurons arrive in the ______ cortex, where conscious comprehension occurs
great auricular nerve
sacral and coccygeal
-posterior spinocerebellar tract
-medial vestibulospinal tract
-lateral corticospinal tract
-lateral vistibulospinal tract
-anterior corticospinal tract
-lateral reticulospinal tract
-medial reticulospinal tract
-muscle spindles are the receptor
-initiated by an increase in muscle length
marked by removal of the moody segment from injurious elements
utilizes an integrating center
inhibits excessive muscle contraction
-marked by actions to stabilize the limb opposite of injurious agents
-marked by actions that stabilize the contralateral limb
-medial vestibulospinal tract
-lateral corticospinal tract
-medial reticulospinal tract
-lateral spinothalamic tract
peripheral nervous system
-posterior root ganglion
motor for muscles of facial expression
pain sensation on the tongue
inhibits cardiac muscle
elevation of the scapulae
Which of the following structures consists mainly of white matter?
infero-lateral movement of the eye
lateral movement of the eye
Which of the following statements is true regarding cerebral lateralization? Check all that apply.
-Left-handed people usually exhibit a wider frontal, parietal, and occipital lobe on the left compared to the same lobes on the right
-Imagination, insight, and artistic skill are usually specialties of the right hemisphere.
-Lateralization develops with age and is not already developed at birth.
the ______ is considered the autonomic control center of the body due to its regulation of hormone secretion, thermoregulation, food and water intake, and circadian rhythms
the majority of all afferent pathways pass through and synapse with neurons of the
the outermost layer of the brain in humans is referred to as the _____ due to its recent evolutionary history
the _______ represents the area of emotional control and includes the amygdala, hippocampus, cingulate gyrus and the fornix.
one of the last areas of the brain to mature fully is the ______ which controls logic, judgment, expression of emotion
acting mostly as a communication relay center due to the many fiber tracts through the area the _____ includes the cerebral peduncles, colliculi, and nuclei of cranial nerves III and IV
composed of three parts, the ______ is an older region which provides basic life support functions including roles in the cardiovascular and respiratory system
the alert system of the body names according to the tracts that provides communication of lower brain with higher brain regions, is the _______
reticular activating system
guards the blood capillaries throughout the brain
utilizes the endothelial cells of the capillaries
astrocytes contribute to the cell junctions
utilizes perivascular feet
utilizes the tight junctions between cells of the choroid plexus capillaries
forms the only tight junctions between ependymal cells
both blood-brain barrier and blood-CSF barrier
consists of tight junctions
permeable to water, glucose, and oxygen
Which of the following is a true statement about the brain barrier system? Check all that apply.
-The brain barrier system is necessary because brain tissue is irreplaceable, and therefore must be well protected.
-Both brain barriers utilize tight junctions to keep harmful substance from getting to the tissue fluid of the brain.
-Alcohol, caffeine, nicotine, and anesthetics can all cross the brain barrier system.
-The brain barrier system is susceptible to trauma and damage.
cavity, space, or division
-communication between adjacent gyri
-communication within hemispheres
-communication between the left primary somatosensory area and a left somatosensory association areas
-communication between hemispheres
-communication between lower and higher brain regions
-communication between the thalamus and the cortex
olfaction and hearing are processed in the
the ____ provides critical function in motivation, logical reasoning, expression of emotion, and social attitudes
housing the visual centers, the ____ receive input from the optic radiation
the frontal lobes also include the primary ______ which control voluntary motor functions
the ______ exhibit receipt and association of general body sensations
the deepest of the cerebral lobes, the _____ is also the smallest and least understood
motor control of the right hand
speech and language comprehension
sensation of the left hand
artistry and creativity
memory of shapes
ipsilateral sensation of the right side of the body
contralateral sensation of the left side of the body
true function or property of cerebrospinal fluid
-maintains the concentration of glycine surrounding the brain
-effectively decreases the brains weight
-produced by the choroid plexus
-cardiac muscle contractions influence the flow of the CSF
false function or property of cerebrospinal fluid
-supplies oxygen to the brain tissue
-blocks blood toxins from brain tissue
-produces antibodies response to antigen exposure in the brain tissue
-compared to levels in the blood plasma, the CSF is higher in glucose
-found in the ventricles of the heart and brain
CSF is secreted into each _____ ventricle by choroid plexus and flows into the third ventricle where more is added
CSF then flows down the cerebral _____ to the fourth ventricle
_____ plexus in the fourth ventricle adds more CSF
CSF then flows out two lateral apertures and one _____ aperture
CSF fills the _____ space and bathes external surfaces of brain and spinal cord
at arachnoid villi, CSF is reabsorbed into venous blood of _____ venous sinuses
Which of the following is a true statement regarding the reticular formation? Check all that apply.
-The reticular formation is responsible for the ability to stand up straight.
-The reticular formation aids the ability to catch a ball.
-Heart rate is regulated by the reticular formation.
-If you step on a tack, the signals causing the perception of pain travel through the reticular formation.
-The reticular formation helps you focus on one conversation in a crowded, noisy room.
-found between the corpus callosum and the fornix
-contains choroid plexus
-between the fornix and midbrain
-between the cerebellum and the pons
-receives CSF directly from the cerebral aqueduct
a space within the dura mater that follows along the longitudinal fissure
-connects the third ventricle to the fourth ventricle
-allows for passage of CSF from the fourth ventricle to extracerebellar space
relays motor nerve signals that control muscle tone and coordination
connected by an intermediate mass
relays sensory nerve signals to the cerebrum
secretes a hormone that enhances childbirth
senses dehydration and makes you feel thirsty
establishes the sleep-wake cycle
connected to the pituitary gland
contains the pineal gland
-folds of this layer form the wall between the cerebral hemispheres
-the superior sagittal sinus is within this layer
-the most superficial layer
-forms the tentorium cerebelli
-forms the structure that partially separates the left and right halves of the cerebellum
this layer is gelatin-like and transparent
the middle layer
-this layer is adhered to the surface of the brain tissue
-blood vessels of the cortical gyri are immediately superficial to this layer
superficial to deep
superficial cortical bone
deep cortical bone
periosteal layer of dura matter
meningeal layer of dura matter
CSF in the subarachnoid space
Determine which brain structure each of the following phrases describes. Then choose the structures that consist of gray matter. Check all that apply.
- The origin of voluntary motor impulses
-The "gateway to the cerebral cortex"
The enzyme acetylcholinesterase, located in the synaptic cleft and on the postsynaptic membrane, breaks ACh down into acetate and choline, thereby stopping the stimulation of a postsynaptic cell.
makes RMP less negative
ATP stores are declining through mitochondrial poison (arsenic)
increased concentration of leaky sodium channels in the membrane
decreased concentration of leaky potassium channels in the membrane
influences the ability of the cell to repolarize
voltage-regulated potassium channels are blocked
acetylcholine esterase concentration is decreased
influences the ability of the cell to depolarize
release of excitatory neurotransmitter by a presynaptic input is blocked
the size of the synaptic cleft is increased
hyponatremia (low ECF sodium)
hyperhydration (high water concentration in ECF)
neurotransmitter synthesis is compromised due to golgi disfunction in the presynaptic neuron
Which of the following describes a reverberating circuit?
There is a prolonged or repetitive effect that lasts until one or more neurons in the circuit fail to fire, or until an inhibitory signal from another source stops one of them from firing and neurons stimulate each other in a linear sequence such as A→B→C→D, but neuron C sends an axon collateral back to A.
Which of the following is not considered an accessory structure of the eye?
The ossicles belong to the middle ear.
A receptor is an axon that carries sensory impulses to the spinal cord's dorsal horn of gray matter.
Divergent sensory pathways explain the phenomenon of referred pain.
The cornea belongs to the tunica fibrosa (fibrous layer) of the eyeball.
Changes in blood pressure are detected by __________ in certain arteries.
Conduction of a nerve impulse would be the fastest in which of the following?
A neuron receives a stimulus. Which of the following events happens next?
Where do most local potentials form in a neuron?
The __________ division tends to prepare the body for action.
An action potential never occurs in dendrites.
The respiratory center gathers information from a variety of sources in order to set the rate and depth of breathing. This is an example of what type of neural circuit?
Half of the fibers of each optic nerve decussate at the __________.
When you spin while sitting in a swivel chair with your eyes closed, you can sense this movement by means of your __________.
The output energy of all receptors is a type of __________ energy.
A nerve fiber is enclosed in its own fibrous sleeve called perineurium.
The upper motor neurons that control skeletal muscles begin with a soma in the __________.
precentral gyrus of the cerebrum
Which of the following nerves originates in the lumbosacral plexus?
Correctly identify and label the structures associated with the brachial plexus at the shoulder level.
Reflex arcs that only use two neurons are called ____________ reflex arcs.
Most nerves are motor nerves.
A stretch reflex is often accompanied by reciprocal inhibition.
Somatic reflexes are responses of skeletal, smooth, and cardiac muscles.
Which of the following is not a function associated with the spinal cord?
Which of the following is correct regarding the occipital lobe
It is the principal visual center of the brain.
Which of the following is not a motor cranial nerve
Vestibulocochlear nerve (VIII)
Sex drive, body temperature, and food and water intake are regulated by which part of the brain
The great majority of which tracts pass through the corpus callosum?
Planning, motivation, and social judgment are functions of the brain associated with which part of the cerebrum?
Unipolar neurons have only a single process leading away from the soma.
Which glial cell is found wrapped around nerve fibers in the PNS?
Which cells form myelin in the spinal cord?
When a neuron is stimulated, Na+ gates open and allow Na+ to exit the cell.
Place the following structures in the order that an electrical impulse would travel beginning with the post-synaptic membrane
node of raniver
Which of the following is true regarding unmyelinated nerve fibers in the PNS?
A Schwann cell folds its plasma membrane around several fibers .
If a neuron is prevented from sending a neurotransmitter across a synapse to another cell, which neuron property is being inhibited?
What occurs during hyperpolarization of a neuron membrane?
Potassium ions are leaving the cell
Which of the following are unencapsulated endings?
Free nerve endings
Where is the primary olfactory cortex located?
Pain, heat, and cold are detected by __________.
free nerve endings
Correctly identify and label the structures associated with tracts of the spinal cord. (green)
anterior corticospinal tract
lateral corticospinal tract
lateral reticulospinal tract
medial reticulospinal tract
lateral vestibulospinal tract
medial vestibulospinal tract
Correctly identify and label the structures associated with the rami of the spinal nerves.
sympathetic chain ganglion
Many upper motor neurons synapse with lower motor neurons in the ___________.
Which reflex shows the least synaptic delay?
The tendon reflex
Which of the following is not a property of reflexes?
Reflexes do not require a stimulus.
Which structure forms the floor and part of the walls of the third ventricle?
Labeling Cerebral White Matter Tracts
Labeling the Surface Anatomy of the Cadaver Brain
Purkinje cells are unusually large neurons found in the cerebellum.
Correctly label the following parts of the brainstem.
lateral geniculate body
medial geniculate body
Cerebrospinal fluid is secreted by choroid plexuses in the __________ ventricles and reabsorbed by arachnoid villi in the __________.
lateral, third, and fourth; superior sagittal sinus
Which of the following structures does not contain CSF?
After a stroke, a patient complains about lack of sensitivity in her right hand. The stroke most likely affected which part of the brain?
Postcentral gyrus in the left parietal lobe