Ch. 15

Question 1

Define somatic nervous system

Answer 1

The part of the vertebrate PNS that controls skeletal muscles and provides afferent information from sensory receptors not associated with internal organs

Question 2

Define autonomic nervous system

Answer 2

The division of the nervous system that innervates and controls autonomic (involuntary) effectors and conveys sensory information from internal organs

Question 3

Define ganglia

Answer 3

Discrete collection of neuronal cell bodies (segmental components of the CNS in invertebrates; components of the PNS in vertebrates)

Question 4

Define afferent

Answer 4

Signal conduction from the PNS to the CNS

Question 5

Define efferent

Answer 5

Signal conduction from the CNS to the PNS

Question 6

Define gray matter

Answer 6

Region of a vertebrate CNS that contains neuronal cell bodies, dendrites, and synapses as well as axons

Question 7

Define white matter

Answer 7

Region of a vertebrate CNS that consists largely of tracts of neuronal axons with an abundance of myelin

Question 8

Define sympathetic

Answer 8

Controls fight/flight

Question 9

Define parasympathetic

Answer 9

Controls rest/relax

Question 10

Define enteric

Answer 10

Controls autonomous movements within the gut

Question 11

Describe the generalized order of a reflex

Answer 11

1. Stimulus
2. Sensory neurons
3. CNS interneurons
4. Motor neurons
5. Effector/movement

Question 12

Contrast gray and white matter.

Answer 12

Gray matter consists of neuronal cell bodies (middle of spine), and white matter consists of myelinated axons (ends of dorsal roots toward the PNS)

Question 13

Nerves that lead from sensory cells to the spinal cord are ______________. Nerves that lead from the spinal cord to the muscle/effector are ________________.

Answer 13

afferent, efferent

Question 14

Contrast neuron length in the SNS vs ANS.

Answer 14

SNS neurons are longer. ANS neurons have ganglia, whereas SNS neurons do not.