A & P 1 Nervous System Lecture Exam
Arrange the following events of an action potential in proper sequence (some steps are left out). 1. Sodium ions diffuse inward. 2. The membrane is depolarized. 3. Repolarization of membrane. 4. Potassium channels open.
1,2,4,3
List the following parts of a reflex arc in the correct sequence starting at the peripheral end. 1. Receptor 2. Motor neuron 3. Effector 4. Association neuron 5. Sensory neuron
1,5,4,2,3
When no stimulus of any magnitude can elicit a response, this is called _____.
Absolute refractory period
During the initial phase of an action potential, the potential difference of the membrane charge _____.
Approaches zero (becomes more positive).
The _________ sulcus separates the frontal lobe from the parietal lobe.
Central
The _____ co-ordinates muscle activity and posture.
Cerebellum
Wallerian degeneration is ...
Degeneration of the distal neuronal process
Areas of the body innervated by specific spinal nerves are termed ___________.
Dermatomes
The outer connective tissue covering of the spinal cord is the _____.
Dura mater
Cranial nerves are part of the peripheral nervous system. Spinal nerves are part of the central nervous system.
False
During the refractory period, only motor impulses will be conducted.
False
Nerves of the peripheral nervous system may be covered with myelin from Schwann cells. The myelin wraps around the axon and dendrite.
False
The autonomic nervous system acts on smooth and skeletal muscle.
False
The autonomic nervous system functions both voluntarily and involuntarily.
False
The spinal cord ends at about ________ in an adult.
L2
The _____ is the area of decusation.
Medulla Oblongata
Which of the following is NOT a type of neuroglial cell?
Motor neuron
An autoimmune disease destroying the myelin sheath is (a) _____.
Multiple Sclerosis
A neuron may synapse with _____.
Muscle cells, glands, and other neurons
At rest there is more extracellular _____ and more intracellular _____ in a neuron.
Na;K
___________ cells in the CNS form myelin.
Oligodendrocyte
The primary motor area of the cerebral cortex lies in the _________ gyrus of the _________ lobe.
Pre-central; frontal
____ produce myelin in the peripheral nervous system.
Schwann Cells
Stimulation of the sympathetic nervous system would generally _____.
Speed up the heart rate
When a nerve fiber is polarized, the concentration of
The concentration of sodium ions is higher on the outside of its membrane and the potassium ion concentration is higher on the inside of the membrane.
Leakage channels are always open.
True
Nerves occur in the peripheral nervous system and tracts only occur in the central nervous system. Nerve fibers are in both the central and peripheral nervous systems.
True
Neuroglial cells can usually divide. Neurons in the brain do not usually divide after birth.
True
___________ matter is formed by an aggregation of __________ processes of many neurons.
White; myelinated
The middle connective tissue covering of the spinal cord is the _____ mater.
arachoid
Sensory tracts are
ascending
The __________ affects cardiac muscle.
autonomic nervous system
Neurotransmitters are released from the _____.
axon
Synaptic bulbs containing neurotransmitters are located in the __________ .
axon
Why is impulse conduction faster on myelinated axons with larger distances between nodes of Ranvier?
because impulses can "jump" (saltate) from node to node
The ____________ plexus forms the radial and ulnar nerve of the arm.
brachial
The central nervous system is composed of the _____.
brain and spinal cord
Neurons are ___________, whereas neuroglial cells are ____________.
cells that provide for action potentials; cells that support and aid the neurons
The _____ controls higher brain functions.
cerebrum
The _____ has 2 hemispheres connected by the corpus callosum.
cerebrum
The peripheral nervous system is composed of the _____.
cranial nerves and spinal nerves
The phrenic nerve inervates the ___________ .
diaphragm
The _____ includes both the thalmus and the hypothalmus.
diencephalon
The _____ is a relay station for sensory impulses.
diencephalon
Sensory nerves form the _____ root of the spinal nerves.
dorsal
"Motor" is referred to as _____.
efferent
There are ________ ventricles in the brain.
four
The _____ lobe controls the movement of skeletal muscle.
frontal
Unmyelinated neurons form _____ matter.
gray
The largest area represented in the motor area of the cerebral cortex is the _____.
head and neck
During depolarization, Sodium moves __________ the neuron.
into
The __________ separates the left and right cerebral hemispheres.
longitudinal fissure
The brain stem is composed of the _____.
midbrain, pons, medulla oblongata
Spinal nerves are best termed _________.
mixed
Damage to the pre-central gyrus would cause a deficit of _____ skills.
motor
During repolarization the inside of the membrane becomes more _____ as the cell returns to RMP.
negative
If a membrane is hyperpolarized, it is more ___________ than at RMP.
negative
The _____ lobe provides for vision.
occipital
The pupils constrict from stimulation by the _____ nervous system.
parasympathetic
The _____ lobe provides for the sensations of temperature, touch, pressure and pain.
parietal
The inner most connective tissue covering of the spinal cord is the _____ mater
pia
The CSF is between the _____ mater.
pia and archnoid
Spinal nerves, except for nerves T2-T12, join to form nerve networks in the cervical, brachial, and lumbosacral regions. Peripheral nerves supplying the limbs originate in these networks. What are these networks called?
plexuses
A viral infection causing motor neuron death in the spinal cord is (a) _____.
poliomyelitis
As depolarization begins the inside of the membrane becomes _____ after threshold is achieved.
positive
At RMP the outside of the membrane is more _____ than the inside.
positive
The sympathetic division of the autonomic nervous system:
prepares the body for an emergency
The sympathetic nervous system _____.
prepares you for an emergency, both real and imagined
Damage to the post-central gyrus would cause a deficit of _____ skills.
sensory
Neurons that transmit impulses toward the central nervous system from the skin and internal organs are:
sensory
The somatic nervous system acts on _____ muscle.
skeletal
The __________ affects voluntary skeletal muscle.
somatic nervous system
Stimulation from the _____ nervous system causes constriction of most blood vessels of non-essential organs.
sympathetic
Stimulation of the _____ nervous system causes dilation of blood vessels to skeletal muscles.
sympathetic
The _____ lobe provides for for hearing.
temporal
A bundle of nerve fibers in the central nervous system is a _____.
tract
Cerebrospinal fluid is removed from the ventricles into the _____.
venous blood
Motor nerves form the _____ root of the spinal nerves.
ventral
The central part of the brain is mostly _____.
white matter