11.2 Skeletal Muscle Part 3 Flashcards
1
Q
What is the sarcoplasmic reticulum?
A
specialized smooth ER that enfolds each myofiber in the cell
2
Q
What is a twitch?
A
smallest measurable muscle contraction
3
Q
How can the nervous system increase the force of contraction?
A
motor unit recruitment and frequency summation
4
Q
What is a motor unit?
A
group of myofibers innervated by branches of a single motor neurons axon
5
Q
What is tetanus?
A
strongest possible muscle contraction
6
Q
What molecule provides the energy for a muscle contraction?
A
ATP
7
Q
What is creatine phosphate?
A
intermediate-term energy storage molecule
8
Q
What is myoglobin?
A
globular protein that provides an oxygen reserve by taking oxygen from hemoglobin and releasing it as needed
9
Q
What are the two categories of muscle fibers?
A
slow twitch fibers
fast twitch fibers
10
Q
A
