Muscles 2 Flashcards
What are the two classifications of muscle fibres?
- Oxidative
- Glycolytic
What are the 2 types of oxidative fibres?
- Slow
- Fast
Mitochondrial levels in oxidative fibres?
High
Which of the two fibres are more vascularised
Oxidative
What is the diameter of oxidative fibres?
Low
What is the function of slow oxidative fibres?
Resisting fatigue
Relative ability to resist fatigue of fast ox fibres?
Intermediate
Mitochondrial levels in glycolytic fibres?
Low
What do glycolytic fibres have a high number of?
- Glycolytic enzymes
- Glycogen
Diameter of glycolytic fibres?
High
Relative ability to resist fatigue of glycolytic fibres
Bad
Where is smooth muscle found in the body?
- Airways
- Sphincters
- GI tract
What is smooth muscle controlled by?
- ANS
Arrangement of actin and myosin in smooth muscle?
- Diagonally
How are actin and myosin anchored to membranes in cardiac muscles?
Dense bodies
What does calcium bind to when it is released from the sarcoplasmic reticulum in smooth muscle?
Calmodulin
What does calmodulin bind to?
Myosin light chain kinase
What is the function of myosin light chain kinase?
Phosphorylates myosin using ATP
What enzyme allows relaxation?
Myosin light chain phosphatase
How does myosin light chain phosphatase work?
Dephosphorylates the myosin cross bridges, causing them to unbind
What does the action of myosin light chain kinase allow in regards to contraction in smooth muscle?
Sustained contraction
Why does the action of myosin light chain phosphatase allow a longer contraction?
Less ATP is used in the contraction on a whole
