ANS

Question 1

What branch of the PNS are the somatic and autonomic systems part of, and what are their functions?

Answer 1

Efferent (motor) division of PNS
Somatic - skeletomotor
Autonomic - control of all organs

Question 2

What is the function of the ANS?

Answer 2

• regulate visceral activities outside the realm of consciousness and voluntary control (such as circulation, digestion, sweating and pupillary size)

Question 3

List features of sympathetic dominance

Answer 3

• increased cardiac output (heart rate x stroke volume)
• generalised vasoconstriction
• vasodilation of blood vessels supplying skeletal muscles
• increased blood pressure
• airway dilation
• pupil dilation (far vision)
• glycogenolysis
• increased sweating
• inhibition of urinary and digestive activities

Question 4

List features of parasympathetic dominance

Answer 4

• increased urinary activity
• increased digestive activity (e.g., insulin secretion, increased motility of digestive tract, relaxation of sphincters)
• stimulation of mucus production in pathways
• constriction of airways

Question 5

List how the exocrine glands (3) are activated i) sympathetically and ii) parasympathetically

Answer 5

Exocrine pancreas:

i) decreased secretion
ii) increased secretion

Sweat glands:

i) increased secretion (most)
ii) increased secretion (some)

Salivary glands:

i) small volume of thick saliva
ii) large volume of watery saliva

Question 6

List how the endocrine glands (2) are activated i) sympathetically and ii) parasympathetically

Answer 6

Adrenal medulla:

i) adrenaline and noradrenaline
ii) none

Endocrine pancreas:

i) decreased insulin
ii) increased insulin and glucagon

Question 7

State what the (2) cholinergic receptors are and i) the site of them and ii) their response to acetylcholine

Answer 7

1. Nicotinic receptor
   i) all autonomic ganglia
   - motor end plate of skeletal muscle fibres, some CNS cell bodies and dendrites
   ii) sympathetic and parasympathetic preganglionic fibers
   - motor neurons, some CNS presynaptic terminals
2. muscarinic receptors
   i) effector cells (cardiac muscle, smooth muscle, glands)
   - some CNS cell bodies and dendrites
   ii) parasympathetic postganglionic fibres
   - some CNS presynaptic terminals

Question 8

Outline the general functions alpha 1 receptors

Answer 8

< adrenaline
> noradrenaline
- excitatory response, contraction of smooth muscle

Arterioles, most sympathetic target tissues

Question 9

Outline the general functions of alpha 2 receptors

Answer 9

< adrenaline
> noradrenaline
- inhibitory response, relaxation of smooth muscle

Digestive tract

Question 10

Outline the general functions of beta 1 receptors

Answer 10

adrenaline = noradrenaline

• excitatory response

Heart (kidney, liver)

Question 11

Outline the general functions of beta 2 receptors

Answer 11

Mostly adrenaline
- inhibitory response, relaxation of smooth muscle

Bronchioles, arterioles

Question 12

Outline the general functions of beta 2 receptors

Answer 12

Mostly adrenaline
- inhibitory response, relaxation of smooth muscle

Bronchioles, arterioles