Nervous system #3

Question 1

Axon

Answer 1

(ak-son) A single elongated projection from a nerve cell body that transmits impulses away from the cell body.

Question 2

Brain

Answer 2

The Largest and most complex unit of the nervous system; the brain is responsible for perception, sensation, emotion, intellect, and action.

Question 3

Central Nervous System

Answer 3

(CNS) The brain and spinal cord and their coverings.

Question 4

Cerebrospinal Fluid

Answer 4

(CSF) a clear, colorless fluid that flows throughout the brain and around the spinal cord, cushioning and protecting these structures and maintaining proper pH balance.

Question 5

Gray Matter

Answer 5

Unmyelinated nervous tissue in the central nervous system.

Question 6

Myelin

Answer 6

A white, fatty insulating substance formed by the Schwann cell that surrounds some axons. Also produced in the central nervous system by oligodendrocytes.

Question 7

Neuroglia

Answer 7

Specialized connective tissue cells that support, protect, and hold neurons together and maintain homeostasis in the nervous system.

Question 8

Neurons

Answer 8

Nerve cells the conduct impulses.

Question 9

Synapses

Answer 9

A space between neurons or between a neuron and an effector organ.

Question 10

Cerebellum

Answer 10

The second largest part of the brain; the cerebellum is involved with balance, posture, coordination, and movement.

Question 11

Cerebrum

Answer 11

The Largest of the brain division; the cerebrum consists of two hemispheres that occupy the uppermost region of the cranium. The cerebrum receives, interprets, and associates incoming information with past memories and then transmits the appropriate motor response.

Question 12

Dendrites

Answer 12

Branching projections from the nerve cell body that carry signals to the cell body.

Question 13

Dorsal root

Answer 13

Also called the posterior root. Prosterior attachment of a spinal nerve to the spinal cord. Transmits sensory information into the spinal cord.

Question 14

Neurolemma

Answer 14

Also called Schwann membrane, sheath of Schwann, and endoneural membrane. The outer cell membrane of Schwann cell that encloses the myelin sheath found on certain peripheral nerves. Essential in regeneration of injured axons.

Question 15

Neurotransmitters

Answer 15

Chemical compounds that generate action potentials when released into the synapses from presynaptic cell.

Question 16

Schwann cell

Answer 16

A specialized cell that forms myelin.

Question 17

Spinal cord

Answer 17

The portion of the central nervous system that exists the skull and extends into the vertebral column. The two major functions of the spinal cord are to conduct nerve impulses and to be a center for spinal reflexes.

Question 18

White matter

Answer 18

Myelinated nerve tissue in the center nervous system.

Question 19

Dermatome

Answer 19

A cutaneous (skin) section supplied by a single spinal nerve.

Question 20

Efferent nerves

Answer 20

Motor nerves that transmit motor impulses; they link the central nervous system to the effectors outside it.

Question 21

Myotome

Answer 21

A skeletal muscle or group of skeletal muscles that receives motor axons from a particular spinal nerve.

Question 22

Plexus

Answer 22

A network of intertwining nerves that innervates a particular region of the body.

Question 23

Mixed nerves

Answer 23

Nerves that contain sensory and motor axons.

Question 24

Cranial Nerves

Answer 24

Twelve pairs of nerves that originate from the olfactory bulbs, thalamus, visual cortex, and brainstem. They transmit information to and from the sensory organs of the face and the muscles of the face, neck, and upper shoulders, as well as organs of the thorax and abdomen.

Question 25

Sympathetic nervous system

Answer 25

The part of the autonomic nervous system that provides for most of the active function of the body; when the body is under stress, the sympathetic nervous system predominantes with fight - flight responses.

Question 26

Thermal receptors

Answer 26

Sensory receptors that detect changes in temperature.

Question 27

Proprioceptors

Answer 27

Sensory receptors that provide the body with information about position, movement, muscle tension, joint activity, and equilibrium.

Question 28

Spinal nerves

Answer 28

Thirty-one pairs of mixed nerves, originating in the spinal cord and emerging from the vertebral column; they are part of the peripheral nervous system.

Question 29

Somatic nervous system

Answer 29

A system of nerves that keeps the body in balance with external environment by trasmitting impulses among the central nervous system, skeletal muscles, and skin.

Question 30

Reflex

Answer 30

An automatic, involuntary reaction to a stimulus.

Question 31

Free nerve endings

Answer 31

Sensory receptors that detect itch and tickle sensations.

Question 32

Parasympathetic nervous system

Answer 32

The energy conservation and restorative system associated with what commonly is called the relaxation response.

Question 33

Brainstem

Answer 33

The inferior, primitive portion of the brain that contains centers for vital function and reflex actions, such as vomiting, coughing, sneezing, posture, and basic movement patterns.

Question 34

Ascending tracts

Answer 34

Tracts in the spinal cord that carry sensory information to the brain.