Muscle Physiology Flashcards
Types of muscle
[3]
Skeletal
Cardiac
Smooth
Function of skeletal muscle
Voluntary control
Helps to move + breathe
Function of cardiac muscle
The heart
Function of smooth muscle
Surround hollow organs
How is contraction initiated
A rise in intracellular calcium
In striated muscles what does calcium bind to
Troponin complex
In smooth muscle what does calcium bind to
Calmodulin
What is the structure of straited muscle
Actin and myosin forming a cross bridge
What is a troponin complex
Calcium binding protein
First step of cross bridge cycle
ATP binds to myosin head
After ATP binds what happens
ATP is hydrolysed
Myosin head goes to resting position
How is a power stroke created
When phosphate is released
Formation changes
Cross bridge cycle
[5]
ATP binds to myosin head
ATP hydrolysed, myosin head goes to resting position
Cross bridge formed
P is released, making power stroke
ADP released
How does action potential change the calcium concentration
AP causes ACh to release
End plate potential initiates an AP
AP cause calcium release from sarcoplasmic reticulum
Increase intracellular calcium conc cause contraction
In skeletal muscle what is needed to cause a strongcontraction
Summation of twitches