ANS

Question 1

What is involved in increased sympathetic tone?

Answer 1

Increase HR and CO Constriction of arteriolar/venous smooth muscle (increased BP) Breakdown of glycogen Airways open Pupils dilate Digestive and urinary activities shut down

Question 2

What is involved in increase parasympathetic tone?

Answer 2

Increased gut activity Emptying of bladder Secretion Slow down sympathetic acitivity stimulation

Question 3

What is meant by antagonistic dual innervation?

Answer 3

Many organs/glands are dually innervated by SNS and PNS, which have antagonistic functions.

Question 4

What are exceptions to antagonistic (1) and dual innervation (2)?

Answer 4

Not all are antagonistic: Salivary glands are innervated by both SNS and PNS but both cause saliva secretion. Not all are dually innervated: Sweat glands and blood vessels are only innervated by sympathetic.

Question 5

What is ganglion location for SNS and PNS?

Answer 5

For parasympathetic division, ganglion sits on the organ (short post-ganglionic neuron). For sympathetic division, ganglion sites far from organ (long post-ganglionic neuron)

Question 6

How do the SNS and PNS differ in where they leave CNS?

Answer 6

Parasympathetic division leaves the CNS in the cranio-sacral portion of the spinal cord.

Sympathetic division leaves the CNS in the thoraco-lumbar section.

Question 7

What is the exception to the normal neurotransmitters that SNS uses?

Answer 7

SNS nerve that controls secretory cells (e.g. sweat glands) use acetylcholine rather than the normal noradrenaline.

Question 8

What is the role of the adrenal medulla?

Answer 8

Composed of modified sympathetic neurones that secrete NA and ADR.