Muscles Flashcards
1
Q
What are important structures in skeletal muscles?
A
Blood vessels; nerves
2
Q
What do blood vessels do?
A
- Deliver nutrients and oxygen (glucose, aa, fats)
- Remove waste (lactic acid, CO2)
- Regulate temperature (help keep at correct temp, remove heat*)
3
Q
What do nerves do?
A
-Stimulate contraction; handle voluntary control
4
Q
What are muscle fascicles?
A
- Many in a body
- In each one, there is a bundle of muscle fibers (cell)
5
Q
Muscle fibers
A
- Contain mitochondria
- Contain energy substrate (fat and glycogen)
- Contain myofibrils
6
Q
Glycogen
A
- polysaccharide
- multiple glucose units
- storage form of carbs in body
7
Q
Myofibrils
A
- Divided into regions called sarcomeres
- many sarcomeres within a myofibril
- contraction occurs within a sarcomere
8
Q
What is a sarcomere?
A
Basic unit of muscle tissue
9
Q
What is involved in the contraction in sarcomeres?
A
- Interaction of 2 types of filament (thick and thin)
- The filaments “slide” across each other “shortening = contracting”, requires Ca+ and ATP
10
Q
Summary of Muscle Contractions
A
- Neural impulse occurs signaling a need to contract
- Ca+ is released
- Ca+ causes a change that allows the thick and thin filaments to interact
- The sarcomere shortens (contraction) (slide)
* 5. ATP is used in this process*
11
Q
Thin filaments
A
Actin
12
Q
Thick filaments
A
Myosin
13
Q
ATP
A
Adenosine triphosphate
14
Q
4 sources of ATP?
A
- Stored ATP (very little)
- Creatine phosphate (little more still not much)
- Anaerobic glycolysis (limited amounts)
- Aerobic metabolism of carbs and fats
15
Q
Anaerobic metabolism
A
- does not need oxygen
- uses carbs, not fats
- results in some ATP and lactic acid
