Muscular System Flashcards
1
Q
Muscular system
A
- skeletal, cardiac, smooth
- over 600
- all muscles can shorten (contract) or relax (elongate)
- have electric gradient which can reverse
2
Q
Skeletal muscle
A
- voluntary
- work in pairs
- muscle fibers bound together in parallel bundles
- striated
3
Q
Smooth muscle
A
- involuntary
- found in walls of internal organs, sphincters or valves
- nonstriated
- shorter and wider
4
Q
Cardiac muscle
A
- involuntary
- found in heart
- striated
5
Q
Skeletal muscle contraction
A
- when contracts, force to attached bones
- consists of muscle fibers, myofibrils, sarcomeres
6
Q
Myofibrils
A
- two protein microfilaments
- thick is composed of myosin
- thin is protein actin
- dark bands in striated = when thick and thin overlap
- contraction occurred when thick slide over thin= shortening sarcomere
7
Q
Action potential
A
- when AP reaches muscle, calcium ions released, which binds to myosin and actin, which binds to myosin heads of thick and thin filaments
- adenosine triphosphate = energy to contract
