Physiology 4 Skeletal muscle
Objectives:
- Be familar with the neuromuscular junction
- Case: myathenia gravis
- Be familiar with the morphology of striated muscle
- Understand how excitation contraction coupling works
Objective based questioning:
Content:
Be familar with the neuromuscular junction (aka motor endplate)
just like a neural synapse where a myofibril is innervated by a single fibre
the choline of acetylcholine is recycled
Case: myathenia gravis
nACh receptors are attacked by antibodies, leading to sequesteration and destruction of nACh receptors
ptosis is droopy eyes
Be familiar with the morphology of striated muscle
actin and myosin troponin and tropomyosin myosin heads
Z line I band actin without myosin A band - myosin H band space between actin
Understand how excitation contraction coupling works
Excitation on the sarcolemma causes DHPR to touch the RYR triggering release of the calcium ions from the sarcoplasmic reticulum. the calcium the bind to the troponinmyosin complex leading to the tropomyosin shifting to reveal the binding sites of the myosin heads for cross bridge cycling.