Chapter 10 Flashcards
acetylcholine
neurotransmitter chemical released at the ends of nerve cells
afferent nerve
carries messages toward the brain and spinal cord (af is a form of ad- meaning toward)
arachnoid membrane
middle layer of the three membranes (meninges) that surround the brain and spinal cord
astrocyte
type of glial (neuroglial) cell that transports water and salts from capillaries in the nervous system
autonomic nervous system
nerves that control involuntary body functions of muscles, glands, and internal organs
axon
microscopic fiber that is part of a neuron and carries nervous impulse along a nerve cell
blood-brain barrier
protective separation between the blood and brain cells; makes it difficult for substances (such as anticancer drugs) to penetrate capillary walls and enter the brain
brainstem
posterior portion of the brain that connects the cerebrum with the spinal cord; includes the midbrain, pons, and medulla oblongata
cauda equina
collection of spinal nerves below the end of the spinal cord
cell body
part of a nerve cell that contains the nucleus
central nervous system (CNS)
brain and spinal cord
cerebellum
posterior part of the brain that coordinates muscle movements and maintains balance
cerebral cortex
outer region of the cerebrum, containing sheets of nerve cells; gray matter of the brain
cerebrospinal fluid (CSF)
circulates throughout the brain and spinal cord
cerebrum
largest part of the brain, responsible for voluntary muscular activity, vision, speech, taste, hearing, thought, and memory
cranial nerves
carry messages to and from the brain to all parts of the head and neck and also (in the case of the vagus nerve) to other parts of the body; 12 pairs
dendrite
microscopic branching fiber of a neuron that is the first part to receive the nervous impulse
dura mater
thick, outermost layer of the meninges surrounding and protecting the brain and spinal cord; Latin for “hard mother”
efferent nerve
carries messages away from the brain and spinal cord; motor nerve
ependymal cell
glial cell that lines membranes within the brain and spinal cord and helps form cerebrospinal fluid
ganglion
collection of nerve cell bodies in the peripheral nervous system
glial cell
supportive and connective nerve cell that does not carry nervous impulses; can reproduce themselves as opposed to neurons
examples are astrocytes, microglial cells, ependymal cells, and oligodendrocytes
gyrus
sheet of nerve cells that produces a rounded ridge on the surface of the cerebral cortex; convolution
hypothalamus
portion of the brain beneath the thalamus; controls sleep, appetite, body temperature, and secretions from the pituitary gland
medulla oblongata
part of the brain just above the spinal cord; controls breathing, heartbeat, and the size of blood vessels; nerve fibers cross over here
meninges
three protective membranes that surround the brain and spinal cord
microglial cell
phagocytic glial cell that removes waste products from the central nervous system
midbrain
uppermost portion of the brainstem
motor nerve
carries messages away from the brain and spinal cord to muscles and organs; efferent nerve
myelin sheath
covering of white fatty tissue that surrounds and insulates the axon of a nerve cell; myelin speeds impulse conduction along axons
nerve
macroscopic cord-like collection of fibers (axons) that carry electrical impulses
neuron
nerve cell that is necessary for impulses to be carried throughout the nervous system; parenchyma of the nervous system
neurotransmitter
chemical messenger released at the end of a nerve cell; stimulates or inhibits another cell, which can be a nerve cell, muscle cell, or gland cell; examples are acetylcholine, norepinephrine, dopamine, and serotonin
oligodendroglial cell; oligodendrocyte
glial cell that forms the myelin sheath covering axons
parasympathetic nerves
involuntary autonomic nerves that regulate normal body functions such as heart rate, breathing, and muscles of the gastrointestinal tract
parenchyma
essential, distinguishing tissue of any organ or system; for the nervous system, includes neurons and nerves
peripheral nervous system
nerves outside the brain and spinal cord; cranial, spinal, and autonomic nerves
pia mater
thin, delicate inner membrane of the meninges
plexus
large, interlacing network of nerves; examples are lumbosacral, cervical, and brachial
pons
part of the brain anterior to the cerebellum and between the medulla and the rest of the midbrain; bridge connecting various parts of the brain
receptor
organ that receives and transmits a stimulus to sensory nerves; the skin, ears, eyes, and taste buds are receptors
sciatic nerve
nerve extending from the base of the spine down the thigh, lower leg, and foot
sensory nerve
carries messages toward the brain and spinal cord from a receptor; afferent nerve
spinal nerves
pairs of nerves, arising one on each side of the spinal column; transmit messages to and from the spinal cord
stimulus
agent of change in the internal or external environment that evokes a response; may be light, sound, touch, pressure, or pain
stroma
connective and supporting tissue of an organ; glial cells make it up in the brain
sulcus
depression or groove in the surface of the cerebral cortex; fissure
sympathetic nerves
autonomic nerves that influence bodily functions involuntarily in times of stress
synapse
space though which a nervous impulse travels between nerve cells or between nerve and muscle or glandular cells
thalamus
main relay center of the brain; conducts impulses between the spinal cord and the cerebrum; sensory messages relayed through to appropriate centers in cerebrum
vagus nerve
tenth cranial nerve (cranial nerve X); branches reach to the larynx, trachea, bronchi, lungs, aorta, esophagus, and stomach
ventricles of the brain
canals in the brain that contain cerebrospinal fluid
