lecture 3- Homeostasis

Question 1

What are the two big divisions of the CNS? what do they control?

Answer 1

Somatic- skeletal muscle

Autonomic system- smooth and cardiac muscle and glands

Question 2

Compare the properties of parasympathetic and sympathetic nervous systems:

1. Where they outflow from the spine?
2. Length of pre-ganglionic fibre
3. Ganglionic transmitter
4. Neuroeffector transmitter

Answer 2

1. Symp= Thoracic and Lumbar
   Parasymp= Cranial and sacral
2. Symp- short
   Parasymp- long
3. Both acetylcholine
4. Symp= noradrenaline (because adrenaline speeds up and so does sympathetic)
   Parasympathetic- acetylcholine

Question 3

Whats the cycle of negative feedback?

Answer 3

1. Sensor
2. Afferent pathway
3. Integrating centre
4. Efferent pathway
5. Effector
6. correction of variable
7. change in variable

Question 4

What is positive feedback?

Answer 4

An inital stimulus caises a response which reinforces itself

Question 5

Give 4 examples of positive feedback

Answer 5

1. Milk production
2. Action potential in nerves
3. Ovulation
4. Blood clotting