The nervous system

Question 1

What is the PNS to CNS pathway called?

Answer 1

Afferent - input.

Question 2

What is the CNS to PNS pathway called?

Answer 2

Efferent - output.

Question 3

What are the PNS neurones/ CNS efferent neurones split into?

Answer 3

The somatic and autonomic system.

Question 4

What are the autonomic neurones split into?

Answer 4

Sympathetic and parasympathetic.

Question 5

What is the somatic system associated with?

Answer 5

Voluntary control.

Question 6

What is the autonomic system associated with?

Answer 6

Control that does not require the conscious brain ie not under voluntary control

Question 7

What is the difference between the sympathetic and parasympathetic systems?

Answer 7

Sympathetic is involved in the fight or flight responses, whereas the parasympathetic system is involved in rest and digest responses.
sympathetic stimulates body processes, and parasympathetic inhibits them

Question 8

What is the significance about the preganglionic fibre in the sympathetic system?

Answer 8

It is short and the postganglionic fibre is long.

Question 9

What is the significance about the preganglionic fibre in the parasympathetic nervous system?

Answer 9

It is long and the postganglionic fibre is short. (vice versa in sympathetic nervous system)

Question 10

What happens in the fight or flight response?

Answer 10

Airways are relaxed, glycogenolysis occurs in the liver, the bladder and stomach muscles are relaxed.

Question 11

What is the neurotransmitter in the somatic system?

Answer 11

Acetylcholine.

Question 12

What are the neurotransmitters in the sympathetic system?

Answer 12

The pre-synaptic neurone is cholinergic that acts on a nictotinic receptor that causes adrenaline to be released which acts on the heart and blood vessels.

Question 13

What neurotransmitters are involved in the parasympathetic nervous system?

Answer 13

A cholinergic neurone activates a nicotinic receptor that causes ACh to be released to stimulate the muscle - this acts on the heart, smooth muscle and sweat glands among others.

Question 14

Are adrenoreceptors and muscarinic receptors G-protein coupled or ligand-gated?

Answer 14

G-protein coupled.

Question 15

what is sympathetic division involved in

Answer 15

inhibits production of saliva
airway relaxation to get more O2 in lungs
pupil dilation to widen vision
incr heart rate
liver breaks glycogen down and releases glucose into blood
inhibit digestion- save enery and pancreas shuts down
secretion of adrenaline and norepinephrine from adrenal medulla
bladder wall relaxes to store urine
constriction of vessels carrying blood to intestines, stomach etc (incr flow to skeletal muscles)

Question 16

what is the parasympathetic division involved in

Answer 16

constricts pupil
stimulates salivation
constricts airways
slows heart rate
stimulates digestion
stimulates pancreas to release insulin and digestive enzymes
badder contracts
activation of vagus nerve causes most responses

Question 17

vagustoff (Ach experiment)

Answer 17

proved chemical transmission occurred across synapses
stimulate vagus nerve, hr slows
remove fluid sample from donor heart, place onto heart without vagus nerve
hr of recipient heart slows- shows chemical transferred, so transmission must be chemical, as you can’t transfer electricity with a pipette