Chapter 22

Question 1

Autonomic Nervous System (ANS)

Answer 1

Regulates involuntary effectors

Effectors — cardiac muscle, smooth muscle, glandular epithelia, and adipose and other tissues.

Two efferent divisions:

1) sympathetic division
2) parasympathetic division

Question 2

Sympathetic Division/Parasympathetic Division

Answer 2

Sympathetic Division consists of neural pathways that are separate from parasympathetic pathways.

Many effectors are dually innervated

Question 3

Dually Innervated Effectors

Answer 3

Many autonomic effectors receive input from both sympathetic and parasympathetic pathways.

Effect of two systems are often antagonistic:

1) one inhibits the effectors
2) the other stimulates the effector

Some autonomic effectors are single innervated, receiving input from only the sympathetic division

Question 4

Enteric Nervous System (ENS)

Answer 4

Intestinal nervous system

Second brain, in the gut

Question 5

Preganglionic Neuron

Answer 5

Awkward but descriptive name.

Conduct impulses from brainstem/spinal cord to an autonomic ganglion

Locating them before the ganglion

Synapses with a second efferent neuron

one of two autonomic neuron

Question 6

Postganglionic Neuron

Answer 6

Second neuron conducts impulses away from the ganglion and to the effectors

one of two autonomic neurons

Question 7

Sympathetic Preganglionic Neuron

Answer 7

Begins with the spinal cord

Horns of the thoracic and lumbar segments of the spinal cord

This reason, the sympathetic division is also called thoracolumbar division

Gray & white rami are sympathetic rami

Question 8

Sympathetic Trunk

Answer 8

Aka sympathetic chain ganglia

Structure the resembles a chain of beads

Question 9

White Ramus

Answer 9

Small branch that split away from other spinal never fibers

Name come from the fact the most of the sympathetic preganglionic fibers within it are myelinated axons

Question 10

Gray Ramus

Answer 10

Short branch that allows some postganglionic axons to return to a spinal nerve

Most postganglionic fibers are unmyelinated

Question 11

Parasympathetic Division

Answer 11

Aka craniosacral division

75% of all parasympathetic preganglionic fibers travel in the vagus nerve (CN X) for a distance of 30cm(1 foot) or more

Question 12

Parasympathetic Ganglion

Answer 12

Have short axons

Question 13

Norepinephrine (NE)

Answer 13

Released by axons called adrenergic fibers

one of two neurotransmitters

Question 14

Acetylcholine (ACh)

Answer 14

Released by axons called cholinergic fibers

one of two neurotransmitters

Binds to cholinergic receptors

Question 15

Cholinergic Receptors

Answer 15

Two main types:

1) Nicotine (N) receptors
- Nicotine (a drug) binds to them

2) Muscarinic (M) receptors
- Muscarine(a toxin from mushrooms) binds to them

Question 16

Nonadrenergic-noncholinergic (NANC) Transmission

Answer 16

Breakthrough drug sildenafil citrate (Viagra) used to treat erectile dysfunction (ED)

Question 17

Pharmacology

Answer 17

The study of drug actions

Question 18

Major function of the Sympathetic Division

Answer 18

Served as an “emergency” system

Know for it “fight or flight” reaction

Question 19

Major function of parasympathetic division:

Answer 19

“Rest and repair”

ACh tends to slow the heartbeat