8- Physiology Of The ANS not finished

Question 1

Where to the sympathetic nerves emerge and describe the ganglionic neurones

Answer 1

 Arise in the thoracic and lumbar regions of the spinal cord
Pre-ganglionic fibre SHORT
 Post-ganglionic fibre LONG
 Ganglia located in a chain close to the
vertebral column (PARAVERTEBRAL GANGLIA) or closer to the target tissue (e.g. COELIAC GANGLION)
o The connections between these ganglia allow MASS ACTIVATION

Question 2

Where to the parasympathetic nerves emerge and describe the ganglionic neurones

Answer 2

 Arise in cranial and sacral regions off spinal cord
 Pre-ganglionic neurone LONG
Post ganglionic neurone short
 Ganglia are located in or very close to the target tissue

Question 3

What would happen if you denervated the heart

Answer 3

if you denervated the heart, the heart rate would increase - the normal influence on the heart rate is very much parasympathetic dominated. Intrinsic hr is 100-110bmp

Question 4

Decreased innervation of the sweat glands

Answer 4

sympathetic innervation that goes to the sweat glands - but in this case, the post-ganglionic sympathetic fibres that innervate the sweat glands DO NOT RELEASE NORADRENALINE (the usual transmitter), they instead release ACETYL CHOLINE so they are CHOLINERGIC SYMPATHETIC FIBRES

Question 5

What nerves make up the parasympathetic nervous system

Answer 5

The top outflow consists of FOUR of the CRANIAL NERVES:
Cranial nerves: Oculomotor Nerve (CN III) Facial Nerve (CN VII) Glossopharyngeal Nerve (CN IX) Vagus Nerve (CN X)
SACRAL REGION where you have an outflow mainly via the splanchnic nerve - the nerves go to the reproductive organs and there is another outflow to the lungs and intestine

Question 6

Describe the nerves make up the sympathetic nervous system

Answer 6

THORACOLUMBAR outflows (T1 - L3)
• The pre-ganglionic fibres tend to leave the
spinal cord and join together in a row of linked ganglia called the sympathetic ganglia in a sympathetic chain that lies adjacent to the spinal cord