Autonomic nervous system Flashcards
1
Q
Autonomic nervous system
A
- Maintains internal environment
- Mostly involuntary
- Controls circulation, digestion and excreation
2
Q
ANS input (afferent)
A
Sensory neurones from peripheral organs to centre of hypothalamus, medulla
3
Q
ANS output (efferent)
A
- Syspathetic or parasymethetic neurones
- Activate same organ
- Opposing effects liked by reflex arcs
4
Q
Viceral sensory neurones
A
- monitor temp, pain, irritation, chemical change and streach in organ
- Receptors scattered localisation poor don’t know where its generated
- Sensory fibres run together with autonomic output neurone
5
Q
ANS nerve controls
A
- Smooth muscle - bronchioles, iris digestive system bladder
- Cardiac muscle
- Secreatory gland
6
Q
Spinal reflex arc
A
- Stimulus to spinal cord integrated then to the preganglionic axon causing a response
- long reflex
7
Q
Control of Autonomic nervous system
A
- Processed in cerbral cortex hat can process autonomic functions such as breathing
8
Q
Sympathetic
A
- Fight or flight
- Short term survival increase energy availability
- Increase heart rate
- Increase lung capacity
- Increase blood flow to essensial skeletal muscle
9
Q
Parasympathetic
A
- Rest and digest
- Long term survival reduces energy availability
- Decrease heart rate
- Decreases lung capacity
- Decreases blood flow to skeletal muscle
10
Q
Autonomic ganglion
A
- 2 neurone series cell body of 1st neurone synapses to second neuron to the organ
- Pre-ganglionic neurone - before the autonomic ganglion
- Post-ganglionic - after the autonomic ganglion
11
Q
Paraympathetic neurones
A
- Controls the heart and the lungs
- long 1st neurone then short neurone
- 1st is meylinated and release acytyl choline
- 2nd releases acytyl choline again
12
Q
Sympathetic neurone
A
- Both neurones are short
- 1st neurone releases acyel choline and is meylinated
- Release noradrenaline on smooth muscle 2nd neurone
13
Q
Ionotropic Receptor
A
- Binding site and channel combined
- No second messenger
- Rapid response
14
Q
Metabotropic receptor
A
- Binding site not combined with a channel
- 2nd messenger/GPCR
- Slower response
15
Q
Nictoinic
A
5 subunits
2 Ach binding sites
(Skeletal muscle), autonomic ganglia, adrenal medulla
Ionotropic / ligand gated
16
Q
Muscarinic
A
7-TM GPCR
3 subtypes
M1 - brain, parietal cells (excitatory)
M2 – heart (inhibitory)
M3 - smooth muscle, glands, (excitatory)
17
Q
Post synamptic receptor
A
- Drug targeting receptor both have the Nicotinic ACH R receptor between 1st and 2nd receptor
18
Q
Adrenoceptors
A
- G-protein coupled receptors (metabotropic)
- Respond to adrenaline, noradenaline
- Noradrenaline actions depending on target
Depending on the downstream molecules that they activate
19
Q
Sypathetic effect on bronchodilation
A
- Relaxes the muscle by the beta adrenoreceptors
