CH 10 Neuro- Definitions Flashcards
acetylcholine
neurotransmitter chemical released at the ends of nerve cells
afferent nerve
af- toward/ferent-carry- towards brain- carries messages towards the brain and spinal cord
arachnoid membrane
middle/spider-like- middle layer of the three membranes (meninges) that surround the brain and spinal cord. arachne means spider.
astrocyte
astro/star, cyte/cell- type of glial (neuroglial) cell that transports water and salts from capillaries in the nervous system
autonomic nervous system
involuntary- nerves that control involuntary body functions of muscles, glands and internal organs
axon
microscopic fiber that is part of a neuron and carries nervous impulses along a nerve cell
blood brain barrier (BBB)
protective separation between the blood and brain cells. this makes it difficult for substances such as anti cancer drugs to penetrate capillary walls to 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 (horse tail)
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 brain containing sheets of nerve cells; gray matter of the brain
cerebreospinal fluid
CSF- circulates throughout the brain and spinal cord
cerebrum
voluntary- largest part of the brain- responsible for voluntary muscular activity, vision, speech, taste, hearing, thought and memory
cranial nerves
nerves carry messages to and from the brain to all parts of head and neck and also (in the case of the vagus nerve) to other parts of the body. there are 12 pairs of cranial nerves.
dendrite
miocroscopic branching fiber of a nerve cell (neuron) that is the first part to receive the nervous impulse
dura mater
hard mother- thich, outermost layer of the meninges surrounding and protecting the brain and spinal cord
efferent nerve
ef-away, ferent- carry- 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
ganglia
plural; ganglion
glial cell (neuroglial cell)
supportive and connective nerve cell that does not carry nervous impulses. examples are astrocytes, microglial cells, ependymal cells, and oligodendrocytes. glial cells can reproduce themselves, as opposed to neurons
gyrus
sheet of nerve cells that produces a rounded ridge on the surface of the cerebral cortex; convolution
gyri
plural; gyrus
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. it stimulates or inhibits another cell, which can be a nerve cell, muscle cell, or gland cell. examples of neurotransmitters are acetylcholine, norepinephrine, dopamine, and serotonin
oligodendroglial cell
glial cell that forms the myelin sheath covering axons. also called oligodendrocyte.
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. the parenchyma of the nervous system includes the neurons and nerves that carry nervous impulses. parenchymal cells of the liver are hepatocytes, and parenchymal tissue of the kidney includes the nephrons, where urine is formed.
peripheral nervous system
nerves outside the brain and spinal cord; cranial, spinal, and autonomic nerves
pia mater
delicate mother; thin, delicate inner membrane of the meninges
plexus
large, interlacing network of nerves. examples are lumbosacral, cervical, and brachial (brachi/o means arm) plexuses. the term originated from the indo-european “plek”, meaning to weave together
plexuses
plural for plexus; more than one plexus
pons
(bridge) part of the brain, anterior to the cerebellum and between the medulla and the rest of the midbrain. it is a 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 receptons
sciatic nerve
nerve extending from the base of the spine down the thigh, lower leg, and foot. sciatica is pain or inflammation along the course of the nerve.
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. they transmit messages to and from the sopinal cord.
stimulus
agent of change in the internal or external environment that evokes a response. it may be light, sound, touch, pressure, or pain. plural; stimuli
stroma
connective and supporting tissue of an organ. glial cells make up the stromal tissue of the brain.
sulcus
depression or groove in the surface of the cerebral cortex; fissure
sulci
sulcus; plural
sympathetic nerves
autonomic nerves that influence bodily functions involuntarily in times of stress
synapse
a point of contact; space through which a nervous impulse travels between nerve cells or between nerve and muscle or glandular cells. from greek; synapsis
thalamus
main relay center of the brain. it conducts impulses between the spinal cord and the cerebrum; incoming sensory messages are relayed through the thalamus to appropriate centers in the cerebrum. latin thalamus means room. the romans, who named this structure, thought this part of the brain was hollow, like a little room.
vagus nerve
tenth cranial nerve (cranial nerve x); it branches to reach the larynx, trachea, bronchi, lungs, aorta, esophagus, and stomach. latin vagus means “wandering” (think vagabond). unlike the other cranial nerves, the vagus leaves the head and wanders into abdominal and thoracic cavities.
ventricles of the brain
canals in the brain that contain cerebrospinal fluid. ventricles are also found in the heart; they are two lower chambers of the heart
epilepsis
laying hold of- overtaken by
ictal/ictus
a blow or stroke
dysarthric
to utter distinctly
somnolent
sleepy
lancinating
shooting; piercing; darting; stabbing pain
