Chapter 11 Pt.2

Question 1

What are the three classifications of nerve fibers?

Answer 1

Mixed, Sensory, and Motor

Question 2

Describe Mixed Nerves

Answer 2

• Nerves that carry impulses both to and from the CNS
• Contain both sensory and motor axons
• All spinal nerves and four pairs of cranial nerves

Question 3

Describe Sensory Nerves

Answer 3

• Nerves that only carry sensory impulses towards the CNS
• Composed of only sensory axons
• Rare (Only three pairs of cranial nerves)

Question 4

Describe Motor Nerves

Answer 4

• Nerves that only carry motor impulses away from the CNS
• Composed of only motor axons
• Rare (Only five pairs of cranial nerves)

Question 5

Define Spinal Nerves

Answer 5

Formed from the fusion of a dorsal and ventral root
Pass through its intervertebral foramen

Question 6

Define Nerve Plexuses

Answer 6

• Plexus is a branching network of spinal nerves
• Nerves do not extend directly to the body part they innervate, instead they network.
• Fibers from each spinal nerve are carried to the body periphery via several different routes of branches

Question 7

Define the Autonomic Nervous System

Answer 7

• Regulates the action of smooth muscle, cardiac muscle, and some glands.
• Divides into two systems: PNS & SNS

Question 8

Define the Parasympathetic N.S.

Answer 8

• Long preganglionic neuron (1st)
• Short postganglionic neuron (2nd)
• Both release ACh
• Arise from the craniosacral region of the spinal cord.

Question 9

Define Sympathetic Nervous System

Answer 9

• Short preganglionic neuron
• Lone postganglionic neuron
• Preganglionic neurotransmitter = Acetylcholine
• Postganglionic neurotransmitter = Norepinephrine (NE)
• Arise from the thoracic and lumbar regions.

Question 10

What is the location of the parasympathetic ganglia?

Answer 10

Located at or near the effector

Question 11

What is the location of the sympathetic ganglia?

Answer 11

Located on either side of the spinal cord far from the effector.

Question 12

What releases Acetylcholine?

Answer 12

Cholinergic fibers

Question 13

What are the two types of Cholinergic Receptors (ACh) ?

Answer 13

1. Nicotinic - stimulatory
2. Muscarinic - can be stimulatory or inhibitory

Question 14

What are the two types of Adrenergic receptors (NE) ?

Answer 14

• Alpha - typically stimulatory
• Beta - typically inhibitory