The NS - ANS & Somatic (W5)

Question 1

What is the difference between CNS & PNS

Answer 1

the CNS is the brain and spinal cord, while the PNS is everything put the CNS i.e. all the nerves in the body

Question 2

What is the
- afferent
- efferent divison

Answer 2

1. Incoming stimuli
   - sensory & visceral
2. Out going information towards muscles

Question 3

Name a function of the ANS

Answer 3

• regulates activities of internal organs ( smooth muscle, cardiac muscle and glands)
• homeostasis

Question 4

Where do the
- sympathetic
- parasympathetic nerves originate from

Answer 4

1. thoracic nerves
2. cranial and sacral nerves

Question 5

What does each nerve conatin

Answer 5

preganglionic, ganglion and post ganaglionic neurons

Question 6

What is the difference between pre and post ganglionic neurons

Answer 6

Pre - myelinated and travel its origin in the brain or spinal cord to a ganglion
Post - unmeylinated neuron begins in and travels from the ganglion to the smooth muscle or gland being innervated

Question 7

Where are
- sympathetic
- parasympathetic
ganglia located and their length

Answer 7

1. located close to CNS - short
2. located close to target organ , if not embedded - lomng

Question 8

What are the paravertbral ganglia

Answer 8

also called sympathetic trunk or chain aligned in a row on each side of the spinal cord

Question 9

What re the prevertrebral ganglia

Answer 9

carry efferent information and are located anterior to the aorta and vertebral column

Question 10

Explain the process of the release of ACh

Answer 10

1. ACh is made form choline and acetyl CoA and placed into a synaptic vesicle
2. AP arrives causing calcium channels to open releasing calcium into the vesicle
3. The calcium moves the ACh vesicle to the plasma membrane where they bind and ACh is released via exocytosis

Question 11

What is the role of acetylcholinesterase

Answer 11

4. Synaptic cleft ACh is broken down rapidly by acetycholinerase
5. Choline is transported back into the axon terminal and is used to make more ACh

Question 12

What are the different kinds of cholinergic receptors

Answer 12

• Nicotinic
• Muscarinic

Question 13

Describe Nicotinic receptors

Answer 13

• work in skeletal muscles
• ACh or nicotine binds they allow +ve ions to flow

Question 14

What effect does an nicotinic receptor have

Answer 14

• overall +ve net flow
• ionotropic meaning ligand binding directly affects the permeability of the channel

Question 15

Describe muscarinic receptors

Answer 15

• ACh or muscarine binds they relase G-proteins which begin a cascade of information

Question 16

What effect does an muscarinic receptor have

Answer 16

• effect is metabotropic. meaning ligand binding alters the permeability of ion channels
• several types may be stimulatory or inhibitory

Question 17

What are adrenoreceptors

Answer 17

when epinephrine or norepinephrine binds they release G proteins which begin a cascade of information

Question 18

What are the subtypes of adreno receptors

Answer 18

alpha and beta
- both are metabotropic

Question 19

What is the role of;
- motor cortex
- basal ganglia
- cerebellum
in motor control

Answer 19

1. plans the movement
2. initiates and maintains the movement
3. coordinates movement by electing correct sequences

Question 20

What are upper and lower motor nuerons

Answer 20

Upper - produce voluntary movements
Lower - produce contraction via motor units

Question 21

What is the corticospinal tract

Answer 21

major neuronal pathway providing voluntary motor function
- using the upper motor neurons

Question 22

What can influence the somatic neurone

Answer 22

sympathetic nerves running along side it and can have receptors that aren’t affecting or creating APs but can release G proteins which can affect what the nucleus is making

Question 23

What are the 2 types of reflex arcs

Answer 23

1. Autonomic reflex arc
   - affects inner organs (often completely unaware of these occurring)
2. Somatic reflex arc
   - affects muscles

Question 24

Describe the pathway of a somatic reflex arc

Answer 24

1. sesnor (or receptor)
2. afferent pathway to the spinal cord or brainstem
3. integrating centre, grey matter of the spinal cord or brainstem synapse
4. efferent pathway to the muscles
5. effector muscles give response

Question 25

Given an example of a monosymaoptic reflex

Answer 25

patellar reflex

Question 26

What are proprioceptors

Answer 26

sensory receptors which receive stimuli from within the body, especially one that responses to position and movement

Question 27

What do proprioceptors measure

Answer 27

tension and rate of shortening by integrating information for many of these

Question 28

What are the types of proprioreceptors

Answer 28

1. Muscle spindles
2. Golfi tendon

Question 29

What do muscle spindles measure

Answer 29

• length