A&P Test
A stimulus either causes an action potential or it doesn't. This is called
an all or none response
Neurotransmitters can be removed from the synaptic cell by
repute into the presynaptic neuron, diffusion out of the synaptic cleft, uptake into astrocytes surround the synaptic cleft, inanition by enzymes such as monomaniac oxidase inhibitors
Each voltage gated NA+ ion channels has two voltage sensitive gates: an activation gate and an inactivation gate. Which of the following would occur during depolarization?
both activation and inactivation gates are open
The perineurium
bundles axons into fascicles
White matter is composed of
bundles of myelinated axons
Mechanoreceptors respond to
compression of receptors
The gray matter on the outer surface of there cerebrum is called the
cortex
What makes up the peripheral nervous system?
cranial nerves and spinal nerves
As the strength of a stimulus is increased, the
frequency of occurrence of action potentials increases
The center sulcus separates the
frontal and parietal lobe
Cell bodies of the peripheral nervous system are located in
ganglia
The following are all parts of a neuron except?
ganglia
The reflex that prevents excessive mention in a muscle is the
golgi tendon reflex
The autonomic nervous system
has two sets of neurons in a series
Axons
have a distal portion that branches to form the presynaptic terminals or terminal bulbs
The absolute refractory period ends when
inactivation gates of voltage gated NA+ ion channels reopen
The midbrain develops from the embryonic region called the
mesencephalon
Which of the following is mismatched? 2
microglia- provide support for the neuron cell body
When two action potentials arrive simultaneously at two different presynaptic terminals that synapse with the same postsynaptic neuron.
spatial summation occurs
The junction between two neurons is a
syapse
The autonomic nervous system prepares the body for physical activity (fight or flight).
sympatheic
The lateral fissure separates the _ from the rest of the cerebrum
temporal lobe
If five action potentials arrive at the same synapse in very close succession, which of the following would occur?
temporal occurs
Most sensory input that ascends through the spinal cord and brainstem projects to the relay center called the
thalamus
The primary somatic sensory or general sensory area is located in
the post central gyrus
The sciatic nerve is composed of the
tibial nerve and common fibular nerve
Hearing loss is the result of damage to what nerve?
vestibulocochlear
An IPSP is inhibitory because
it hyperpolarizes the postsynaptic membrane
There are__ pairs of spinal nerves and _ pairs of cranial nerves
31;12
Which of the following is correctly associated with the medulla obligate?
It contains nuclei for regulation of heart rate and blood vessel diameter
Which of the following statement regarding neuroglia is false?
Neuroglia produce action potentials for skeletal muscles
Th short period of time that an action potential can not happen?
absolute refactory period
Which of the following activities is not associated with the cerebrum
acting as a control center of the autonomic nervous system
Decreased sensitivity to a continued stimulus is called
adaptation
The white matter of the cerebellum forms a branching network known as the
arbor vitae
Microglia
are phagocytic cells in the CNS
Dendrites
are the input part of the neuron
Which of the following events in NOT a characteristic of an action potential?
as sodium ions enter, the inside of the plasma membrane becomes more negative
A neuroglial cell that is a major component of the blood brain barrier is the
astrocytes
Which of the following nerves is part of the brachial plexus?
axillary
The substance nigra interconnects with the
basal nuclei or striatum
During the absolute refractory period, the cell
cannot produce another action potential
Neurotransmitters
cause the production of local (graded) potentials in the postsynaptic membrane
Most protein synthesis in neurons occurs in
cell bodies
Which of the following is responsible for conscious thoughts?
central nervous system
Nerves fibers in the phrenic nerves that innervated the diaphragm arise primarily from what plexuses?
cervical
An inhibitory postsynaptic potential (IPSP)can result from the influx of
chloride ions
The cerebral medulla
consists of many nerve tracts of white matter beneath the cerebral cortex.
Which of the following is NOT a function of the cerebellum?
control the heart rate
When two or more presynaptic neurons synapse with a singe postsynaptic neuron in the CNS, a _pathway is formed?
convergent
The sensory (afferent) division of the peripheral nervous system
conveys actions potential to the CNS
The fact that the right side of the brain controls the left side of the body is partially due to the
decussation of the pyramid in the medulla
Which of the following situation occurs in electrically editable cells?
depolarization causes voltage gated sodium ion channels to open
The branch of a spinal nerve that innervated deep muscle along the vertebral column is the
dorsal ramus
The sensory root of a spinal nerve is also referred to as
dorsal root
Overproduction of cerebrospinal fluid could be the result of overactivity of the
ependymal cell
If a withdrawal reflex is initiated in one leg, the crossed extensor reflex causes
extension of the opposite leg
The withdrawl reflex tend to bring the body towards
fetal position
Which of the following brain areas serves as the major control center of the endocrine system?
hypothalamus
A local (graded) potential
increases or decreases in direct proportion to the stimulus strength
The stalk that connects the hypothalamus to the hypophysis to pituitary gland is the
infundibulum
The basal nuclei funtion to
inhibit unwanted muscular activity
What are the nerve fibers that connect the two loves of the thalamus and pass through the third ventricle?
intermediate mass
A neuromodulator
is a substance released from neurons that influences the sensitivity of neurons to neurotransmitters.
A change in resting membrane potential confined to a small area is called a
local (graded) potenial
Which portion of the brainstem is continuous with the spinal cord?
medulla oblogata
The branchial plexus supplies nerves that function contract which of the following
muscle of the arm and forearm
Using the bicep branchii to flex the forearm requires innervation of the_nerve?
musculocutaneous
The gaps in the myelination of myelinated axons are
node of ranvier
Adduction of the thigh involves the
obturator nerve
An action potential
occurs when the local (graded) potential reaches threshold level
Neurons arranged in a circular pathway form
oscillatory circuits
Which division of the autonomic nervous system regulates resting and vegetative function such as digesting food or tempting of the urinary bladder?
parasympatheic
What is and extensive network of axons, and sometime neuron cell bodies, located outside CNS?
plexus
Neurotransmitters are release from the
presynaptic terminal
Synaptic vesicles contain neurotransmitters and are present in the
presynaptic terminals or terminal bulbs
The adaptive signifiancae of the crossed extensor reflex when a person steps on a sharp object is to
preven the person from falling down
The ability to localize the position of body parts is called
proprioception
Extending forearm, wrist, and fingers requires innervation of the _ nerve.
radial
what are function of the nervous system?
receiving sensory input, controlling muscles and gands, maintaining homestasis, establishing mental activity
A decrease in the number of voltage gated Ca2+ ion channels in the presynaptic terminal would
reduce or inhibit exocytosis of neurotransmitters into the synapse
Reciprocal innervation
reinforces the withdrawal reflex by relaxing the antagonistic muscles
Which of the following is mismatched? 3
ruffini's end organs- temperature
What kind of cells are NOT park of the glia of the CNS?
schwann cells
Schwann cells differ from oligodendrocytes in which of the following ways?
schwann cells form a myelin sheath around a portion of only one axons, while oligodendrocytes can surround portions of several axons
A neuron that contains pain sensation to the central nervous system would be classifies as a
sensory or afferent neruron
The parasympathetic nervous system is characterized by
short postganglionic axons near the organs they innervate
Which of the following is mismatched? 1
somatic nervous system - sensory division of PNS
Cerebrospinal fluid fills the
subarachnoid space
The part of the brain that controls the reflex of turning you hear towards a sudden bright light, loud sound, or someone grabbing you is the
superior colliculi
What do astrocytes do?
support neurons, promote neuroinflammation, regulate extracellular brain fluid composition, uptake neurotransmitters from the synapse
The optic nerve
transmits action potentials from the retina
The motor (efferent) division of the peripheral nervous system
transmits impulses from the CNS to skeletal muscle
When a person hits their "funny bone," they cause temporary damage to the _____ nerve.
ulnar
Which nerve has branches that extend to the thoracic and abdominal viscera?
vagus nerve
The motor root of a spinal nerves is also referred to as the
ventral root
Cerebrospinal fluid is formed by tissue in the walls and roofs of the
ventricles of the brain
Suppose both excitatory and inhibitory neurons synapse with a single postsynaptic neuron. What determines if an action potential is initiated in the postsynaptic neuron?
whether threshold is reached or not