anatomy Ch 7 Test review Flashcards
the brain and spinal cord
Central Nervous System (CNS)
a system of nerves that connects the outlying parts of the body with the CNS
Peripheral Nervous System (PNS)
a division of the PNS; also called the voluntary nervous system
somatic nervous system
division of the nervous system that functions involuntarily; innervates cardiac muscle, smooth muscle, and glands
autonomic nervous system
the nonneuronal tissue of the CNS that performs supportive and other functions; also called glia
neuroglia (glial, glia)
abundant star-shaped cells that account for nearly half of the neural tissue, help protect the neurons from harmful substances that might be in the blood, help control the chemical environment in the brain by “mopping up” leaking potassium ions and recapturing released neurotransmitters
astrocytes
spiderlike phagocytes that dispose of debris, including dead brain cells & bacteria
microglia
line central cavity of the brain and spinal cord, their cilia help to circulate the cerebrospinal fluid that fills those cavities and form a protective cushion around the CNS
ependymal
glia that wrap their flat extensions tightly around the nerve fibers, producing fatty insulating coverings called myelin sheaths
oligodendrocytes
supporting cells in PNS, form myelin sheaths around nerve fibers found in PNS
Schwann cells
supporting cells in PNS, act as protective, cushioning cells
satellite cells
cells of the nervous system specialized to transmit messages throughout the body
neurons (nerve cells)
metabolic center of the neuron
cell body
neuron process that carries impulses away from the nerve cell body; efferent process; the conducting portion of a nerve cell
axon
the region of communication between neurons
synapse
a white fatty lipid substance
myelin ( myelin sheath)
the white substance of the CNS; the myelinated nerve fibers
white matter
the gray area of the CNS; contains unmyelinated nerve fibers and nerve cell bodies
gray matter
carries nerve impulses to the CNS
sensory neurons
nerve cells that carry impulses toward the CNS
afferent neurons
neurons that conduct impulses away from the CNS
efferent neurons
a receptor located in a muscle or tendon; concerned with locomotion, posture, and muscle tone
proprioceptors
an electrical event occurring when a stimulus of sufficient intensity is applied to a neuron or muscle cell, allowing sodium ions to move into the cell and reverse polarity
action potential
the loss of a state of polarity; the loss of a negative charge inside the plasma membrane
depolarization
a local change in membrane potential that varies directly with the strength of the stimulus, declines with distance
graded potential
restoration of the membrane potential to the initial resting polarized state
repolarization
an outward fold of the surface of the cerebral cortex, ridge in the brain
gyri
a groove or cleft; the deepest depressions or inward fold on the brain, deep groove
fissures
a prominent groove on the lateral surface of the cerebral hemisphere that separates the frontal and parietal lobes, shallow groove
central salcus
receives impulses from the body’s sensory receptors, pain, temperature, and light touch, allows us to consciously move skeletal muscles, Broca’s area, outer layer of the cerebrum
cerebral cortex
allows us to consciously move skeletal muscle, located anterior to the central sulcus in the frontal lobe, motor neurons form ( corticospinal) tract
primary motor area
involved with the ability to speak, the left hemisphere base of the precentral gyrus
broca’s area
a structure in the middle of your brain that connects the left and right hemispheres
corpus callosum
a mass of gray matter in the diencephalon of the brain, processes sensory and motor info and send it to cerebral cortex
thalamus
the region of the diencephalon forming the floor of the third ventricle of the brain, controls vital functions
hypothalamus
slight brain injury, typically little permeant brain damage occurs, happens when brain is hit or shaken
concussion
marked nervous tissue destruction occurs, coma may occur, bruising of the brain
contusion
stroke, blood circulates to a brain area is blocked and brain tissue can die, loss of some functions or death may occur
cerebrovascular accident (CVA)
paralysis of one side of the body
hemiplegia
temporary brain ischemia (restriction of blood flow) numbness, temporary paralysis, impaired speech
transient ischemic attack (TIA)
what are the parts of a neuron?
Cell body, dendrites, axon, myelin, axon terminal, nodes of ranvier
what does an axon do?
carriers impulses away from the cell body
what do dendrites do?
receive messages from other cells
What does myelin do?
increase action potential conduction speed
what does the cell body do in the neuron?
transfer electrical signals from the dendrites to the axon
what are the two parts of the nervous system?
central and peripheral
what nervous system is based off structure?
Central
what nervous system is based off function?
peripheral
What are two division of the PNS
sensory (afferent) and motor (efferent)
what are two parts of the motor division?
somatic and autonomic
which part of motor division is involuntary?
autonomic nervous system
which part of motor division is voluntary?
somatic nervous system
what are the divisions of the autonomic nervous system?
sympathetic and parasympathetic division
what part of the autonomic nervous system controls the fight or flight
sympathetic division
what are the support cells of the CNS
astrocytes, microglia, ependymal cells, oligodendrocytes
what are the support cells of the PNS
schwann cells and satellite cells
what do astrocytes do?
form blood brain barrier
what do microglia do?
dispose of debris
what do ependymal cells do?
produces CSF
what do oligodendrocytes do?
produce myelin
what do satellite cells do?
protect neuron cell bodies
what do Schwann cells do?
form myelin sheath
what is the difference between white and gray matter?
Gray matter has cell bodies, while white matter has myelinated axons
what does white matter do?
carry signals from one part of the CNS to another
what does gray matter do?
processes info from the sense organs and controls the body’s movements
what are the three types of neurons?
sensory, motor, interneurons
what is the function of an interneuron?
connects sensory neurons to motor neurons
what is a function of a motor neuron
carry info from brain and spinal cord to muscles
what are the parts of the diencephalon?
thalamus, hypothalamus, epithalamus
what is the cerebellum?
mini-brain, responsible for muslce contraction & balance
what are the functions of the brain stem?
breathing, heart rate, blood pressure
parts of the brain stem
midbrain, pons, medulla
what is a TBI?
traumatic brain injury
what is RAS?
reticular activating system, control sleep schedule
difference between somatic and autonomic
somatic is self control and autonomic is automatic
what is the Broca’s area responsible for?
speech
what are parts of the meningeal layer?
Dura Mater, Arachnoid, Pia Mater
what are steps of a reflex arc?
receptor, sensory neuron, interneuron, motor neuron, effector
what causes an action potential?
stimulus
parts of an action potential?
stimulus, depolarization, repolarization, hyperpolarization, resting membrane potential
what does CSF form?
choroid plexuses
where is CSF?
subarachnoid space
what is the corpus callosum?
connects the two hemispheres, allows communication
what is the purpose of the parasympathetic and sympathetic division?
they work together to maintain homeostasis
what happens in the action potential?
sodium channels close, and potassium channels open
where does CSF not go?
brain tissue, peripheral nerves, bloodstream, epidural space
how many cranial nerves are there?
12 pairs
how many spinal nerves are there?
31 pairs
what is the function of the parietal lobe
touch, temperature, pain, spatial awareness
what is the function of the frontal lobe
reasoning and judgment, speech production, emotions
what is the fuction of occipital lobe
vision
what is an axon hillock?
where the axon connects to the cell body
what does the primary motor area do
sends impulses to skeletal muscles
what is the medulla oblongatas function
blood pressure, water balance, survival function
what is the pons functions
relays sensory info to the cerebellum and thalamus
what is the midbrains function
es ascending impulses to the brain and descending impulses to the spinal cord
what is the cerebrums function
ability to read, write, speak
