Nervous System Vocabulary

Question 1

Axon

Answer 1

A large nerve fiber coming off the neuron. The part of the neuron that conducts an impulse away from the neuron cell body.

Question 2

Dendrite

Answer 2

The small nerve fibers of the neuron. The part of a neuron that receives input from other neurons towards the neuron cell body.

Question 3

Myelin

Answer 3

The fatty material that forms a sheath-like covering around some axons (nerve fibers).

Question 4

Neurilemma

Answer 4

Sheath formed by Schwann cells on the exterior of some axons. Covers the myelin.

Question 5

Sensory Receptor

Answer 5

Specialized structure
specific to detecting a
particular sensation and triggering a nerve impulse in response (hair cells,
nerve endings, etc)

Question 6

Central Nervous System

Answer 6

The brain and the spinal cord.

Question 7

Peripheral

Nervous System

Answer 7

Any part of the nervous system outside of the

central nervous system.

Question 8

Somatic Nervous System

Answer 8

The voluntary part of the peripheral nervous system (motor pathways) that lead to and control skeletal
muscle.

Question 9

Autonomic

Nervous System

Answer 9

The involuntary part of the peripheral nervous system (motor pathways) that lead to and control organs.

Question 10

Sympathetic

Nervous System

Answer 10

Part of the autonomic

nervous system that stems in the thoracic and lumbar regions of the spine. Nerves that control organs.

Question 11

Parasympathetic Nervous System

Answer 11

Part of the autonomic

nervous system that stems from the brain and sacral region of the spinal cord. Nerves that control organs.

Question 12

Facilitation

Answer 12

Subthreshold stimulation of a neuron that increases responsiveness to further stimulation.

Question 13

Reflex

Answer 13

A rapid automatic response to a stimulus.

Question 14

Divergence

Answer 14

Spreading apart. A single neuron synapses with two or more post synaptic cells.

Question 15

Convergence

Answer 15

A muscle or gland that
effects change in the body. Two or more neurons
forming synapses with the same neuron.

Question 16

Effector (nervous system)

Answer 16

A nerve ending that carries an impulse away from the central nervous system to
effectors such as muscle or glands.

Question 17

Ganglion

Answer 17

Mass of neuron cell bodies, usually outside the central nervous system.

Question 18

Nissl Body

Answer 18

Material consisting of
granular endoplasmic
reticulum and ribosomes and occurring in nerve cell bodies and dendrites. Site of protein synthesis in the neuron.

Question 19

Meninges

Answer 19

The three membranes that cover the brain and spinal cord.

Question 20

Plexus

Answer 20

Network of interlaced

nerves or blood vessels.

Question 21

Neurotransmitter

Answer 21

Chemical secretes by

neuron into the synaptic space that stimulates or inhibits muscle, gland, or other neurons.