Book Vocabulary

Question 1

afferent nerve

Answer 1

Carries messages toward the brain and spinal cord (sensory nerve). Afferent comes from af- (a form of ad-, meaning toward) and -ferent (meaning carrying).

Question 2

arachnoid membrane

Answer 2

Middle layer of the three membranes (meninges) that surround the brain and spinal cord.The Greek arachne means spider.

Question 3

astrocyte

Answer 3

Type of glial (neurological) cell that transports water and salts from capillaries.

Question 4

autonomic nervous system

Answer 4

Nerves that control involuntary body functions of muscles, glands, and internal organs.

Question 5

axon

Answer 5

Microscopic fiber that carries the nervous that carries the nervous impulse along a nerve cel.

Question 6

blood-brain barrier

Answer 6

Protective separation between the blood and brain cells. This makes it difficult for substances (such as anticancer drugs) to penetrate capillary walls and enter the brain.

Question 7

brainstem

Answer 7

Posterior portion of the brain that connects the cerebrum with the spinal cord; includes the pons and medulla oblongata.

Question 8

cauda equina

Answer 8

Collection of spinal nerves below the end of the spinal cord.

Question 9

cell body

Answer 9

Part of a nerve cell that contains the nucleus.

Question 10

central nervous system (CNS)

Answer 10

The brain and spinal cord.

Question 11

cerebellum

Answer 11

Posterior part of the brain that coordinates muscle movements and maintains balance.

Question 12

cerebral cortex

Answer 12

Outer region of the cerebrum, containing sheets of nerve cells; gray matter of the brain.

Question 13

cerebrospinal fluid (CSF)

Answer 13

Circulates throughout the brain and spinal cord.

Question 14

cerebrum

Answer 14

Largest part of the brain; responsible for voluntary muscular activity, vision, speech, taste, hearing, thought, and memory.

Question 15

cranial nerves

Answer 15

Twelve pairs of nerves that carry messages to and from the brainwith regard to the head and neck (except the vagus nerve).

Question 16

dendrite

Answer 16

Microscopic branching fiber of a nerve cell that is the first part to receive the nervous impulse.

Question 17

dura mater

Answer 17

Thick outermost layer of the meninges surrounding and protecting the brain and spinal cord. Latin for “hard mother.”

Question 18

efferent nerve

Answer 18

Carries messages away from the brain and spinal cord; motor nerve. Efferent comes from ef- (meaning away from) and -ferent (meaning to carry).

Question 19

ependymal cell

Answer 19

Glial cell that lines membranes within the brain and spinal cord and helps form cerebrospinal fluid.

Question 20

ganglion (plural: ganglia)

Answer 20

Collection of nerve cell bodies in the peripheral nervous system.

Question 21

glial cell (neuroglial cell)

Answer 21

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.

Question 22

gyrus (plural: gyri)

Answer 22

Sheet of nerve cells that produces a rounded ridge on the surface of the cerebral cortex; convolution.

Question 23

hypothalamus

Answer 23

Portion of the brain beneath the thalamus; controls sleep, appetite, body temperature, and secretions from the pituitary gland.

Question 24

medulla oblongata

Answer 24

Part of the brain just above the spinal cord; controls breathing, heartbeat, and the size of blood vessels; nerve fibers cross over here.

Question 25

meninges

Answer 25

Three protective membranes that surround the brain and spinal cord.

Question 26

microglial cell

Answer 26

Phagocytic glial cell that removes waste products from the central nervous system.

Question 27

motor nerve

Answer 27

Carries messages away from the brain and spinal cord to muscles and organs; efferent nerve.

Question 28

myelin sheath

Answer 28

Covering of white fatty tissue that surrounds and insulates the axon of a nerve cell. Myelin speeds impulse conduction along axons.

Question 29

nerve

Answer 29

Macroscopic cord-like collection of fibers (axons and dendrites) that carry electrical impulses.

Question 30

neuron

Answer 30

Nerve cell that carries impulses throughout the body; parenchyma of the nervous system.

Question 31

neurotransmitter

Answer 31

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.

Question 32

oligodendroglial cell

Answer 32

Glial cell that forms the myelin sheath covering axons. Also called oligodendrocyte.

Question 33

parasympathetic nerves

Answer 33

Involuntary, autonomic nerves that regulate normal body functions such as heart rate, breathing, and muscles of the gastrointestinal tract.

Question 34

parenchyma

Answer 34

Essential, distinguishing tissue of any organ or system. The parenchyma of the nervous system includes the neurons and nerves that carry nervous inpulses. Parenchymal cells of the liver are hepatocytes, and parenchymal tissue of the kidney includes the nephrons, where urine is formed.

Question 35

peripheral nervous system

Answer 35

Nerves outside the brain and spinal cord: cranial, spinal, and autonomic nerves.

Question 36

pia mater

Answer 36

Thin, delicate inner membrane of the meninges.

Question 37

plexus (plural: plexuses)

Answer 37

Large, interlacing network or nerves. Examples are lumbosacral, cervical, and brachial (brachi/o means arm) plexuses). The term originated from the Indo-European plek, meaning to weave together.

Question 38

pons

Answer 38

Part of the brain anterior to the cerebellum and between the medulla and the rest of the midbrain (Latin pons means bridge). It is a bridge connecting various parts of the brain.

Question 39

receptor

Answer 39

Organ that receives a nervous stimulus and passes it on to afferent nerves. The skin, ears, eyes, and taste buds are receptors.

Question 40

sciatic nerve

Answer 40

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.

Question 41

sensory nerve

Answer 41

Carries messages toward the brain and spinal cord from a receptor; afferent nerve.

Question 42

spinal nerves

Answer 42

Thirty-one pairs of nerves arising from the spinal cord.

Question 43

stimulus (plural: stimuli)

Answer 43

Agent of change (light, sound, touch) in the internal or external environment that evokes a response.

Question 44

stroma

Answer 44

Connective and supporting tissue of an organ. Glial cells are the stromal tissue of the brain.

Question 45

sulcus (plural: sulci)

Answer 45

Depression or groove in the surface of the cerebral cortex; fissure.

Question 46

sympathetic nerves

Answer 46

Autonomic nerves that influence bodily functions involuntarily in times of stress.

Question 47

synapse

Answer 47

Space through which a nervous impulse travels between nerve cells or between nerve and muscle or glandular cells. From the Greek synapsis, a point of contact.

Question 48

thalamus

Answer 48

Main rely 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.

Question 49

vagus nerve

Answer 49

Tenth cranial nerve (cranial nerve X); its branches reach to the larynx, trachea, bronci, lungs, aorta, esophagus, and stomach. Latin vagus means wandering. Unlike the other cranial nerves p, the vagus leaves the head and “wanders” into the abdominal and thoracic cavities.

Question 50

ventricles of the brain

Answer 50

Canals in the brain that contain cerebrospinal fluid. Ventricles are also found in the heart. They are the two lower chambers of the heart.

Question 51

acetylcholine

Answer 51

Neurotransmitter chemical released at the ends of nerve cells.