Muscle Structure Flashcards
1
Q
what does the peripheral nervous system split into
A
somatic
autonomic
2
Q
somatics vs autonomic
A
somatic = conscious activity autonomic = unconscious e.g. digestion
3
Q
what does the autonomic split into
A
sympathetic
parasympathetic
4
Q
sympathetic vs parasympathetic
A
sym = fight or flight parasym = rest and digest
5
Q
name 5 parts of the brain
A
- cerebrum
- hypothalamus
- medulla oblongata
- cerebellum
- pituitary gland
6
Q
cerebrum =
A
vision, hearing, learning, thinking
7
Q
hypothalamus =
A
regulates body temp
8
Q
-medulla oblongata =
A
breathing + heart rate
9
Q
cerebellum =
A
muscle coordination, balance
10
Q
-pituitary gland =
A
releases hormones, stimulates other glands
11
Q
what pressure receptors detect blood pressure in the carotid arteries and aorta
A
baroreceptors
12
Q
what chemical receptors detect O2, CO2 and pH in the carotid arteries, medulla oblongata and aorta
A
chemoreceptors
13
Q
describe step to muscle contraction
A
- action potential depolarises sarcolemma
- spreads down sarcolemma, down t tubules, to sarcoplasmic reticulum, releasing stored Ca2+ ions into sarcoplasm
- ions trigger muscle contraction, ions bind to troponin, changing shape
- this pulls attached tropomyosin out of actin-myosin binding site on the actin filament.
- this exposes the binding site allowing the myosin head to bind. forms actin-myosin cross bridge
- ions also activate ATPase, breaks down ATP to provide energy needed for contraction
- energy released moves myosin head to the side, pulling actin filament along
- ATP also provides energy to break actin-myosin cross bridge, so myosin heads detach after moving.
- head returns to original position, binds to new site on actin, cycle repeats.
- when muscle stops being stimulated, ions leave binding site on troponin(return to sarcoplasmic reticulum), pulling tropomyosin back to block actin-myosin binding site.
- sarcomere lengthens
