W3 - Autonomic NS (part of PNS)

Question 1

What 3 things do somatic innervate and what do they control?

Answer 1

Skin, skeletal muscle and joints - movement and posture

Question 2

What 3 things does the ANS innervate and what does it do?

Answer 2

Internal organs, blood vessel and glands to maintain internal environment

Question 3

What is the main organiser of the ANS and do ascending/descending connections carry this out?

Answer 3

Hypothalamus, descending

Question 4

What is a description of homeostasis?

Answer 4

Dynamic balance between parasymp (rest/digest) and symp branches (fight/flight)

Question 5

Not all structures are dually innervated (sweat glands only symp) but most are controlled by antagonistic para/symp divisions, give the example of the iris of the eye

Answer 5

Parasymp - contstriction of pupil, symp - dilation of pupil

Question 6

Where do the parasympathetic nerves originate?

Answer 6

The cranio-sacral region

Question 7

What cranial/sacral nerves are involved in the ANS?

Answer 7

Cranial - III, VII, IX, X and Sacral - 2, 3, 4

Question 8

Where do sympathetic nerves originate?

Answer 8

Thoraco-lumbar region T1-L2

Question 9

What maintains the internal visceral environment by relaying visceral info to CNS?

Answer 9

Visceral afferents

Question 10

What two information types are relayed to the CNS by visceral afferents?

Answer 10

Physiological (good/normal) and pathophysiological (bad)

Question 11

What three general stimuli do visceral afferents monitor?

Answer 11

Nociception, mechanical and chemical stimuli

Question 12

Do symp/para usually relay nociceptive or physiological info?

Answer 12

Symp - nociceptive, Para - physiological

Question 13

What two neurons do visceral motor efferent pathways consist of?

Answer 13

A lightly myelinated pre-ganglionic neuron and an unmyelinated post-ganglionic neuron

Question 14

In the symp/para NS, are the pre-ganglioinic/post-ganglionic fibres shorter?

Answer 14

Symp - pre = shorter, Para - post = shorter

Question 15

What NTM does a short pre neuron use in symp?

Answer 15

Acetylcholine

Question 16

What NTM does a longer post neuron use in symp?

Answer 16

Noradrenaline

Question 17

What NTM does a long pre neuron/short post neuron use in parasymp?

Answer 17

Both use acetylcholine

Question 18

4 cranial nerves carry para info, what do they do?

Answer 18

III - pupil size, VII - saliva/tears production, IX- saliva production, X - every other para info in body (90%)

Question 19

What parasympathetic axons do the vagus nerve carries?

Answer 19

Preganglionic

Question 20

Where are the nuclei found in the sacral parasymp motor nerves in the SC and where do these axons project to?

Answer 20

Lateral horn, lower organs

Question 21

Where are sympathetic preganglionic neurons located in the thoracolumbar SP before they project to the sympathetic chain ganglia through white ramus?

Question 22

What do prevertebral ganglia contain?

Answer 22

Cell bodies of neurons that innervate abdominal and pelvic cavities

Question 23

Which structure allows for a coordinated response from stimulus?

Answer 23

Sympathetic chain

Question 24

What adrenal medulla controls hormones that initiate fight/flight, what are these two main HMs?

Answer 24

Adrenaline and noradrenaline

Question 25

Sympathetic preganglionic fibres project directly/indirectly to cells of adrenal medulla to elicit a widespread symp response to stress?

Answer 25

Directly