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Flashcards in Muscles 2 Deck (22):
1

What are the two classifications of muscle fibres?

- Oxidative
- Glycolytic

2

What are the 2 types of oxidative fibres?

- Slow
- Fast

3

Mitochondrial levels in oxidative fibres?

High

4

Which of the two fibres are more vascularised

Oxidative

5

What is the diameter of oxidative fibres?

Low

6

What is the function of slow oxidative fibres?

Resisting fatigue

7

Relative ability to resist fatigue of fast ox fibres?

Intermediate

8

Mitochondrial levels in glycolytic fibres?

Low

9

What do glycolytic fibres have a high number of?

- Glycolytic enzymes
- Glycogen

10

Diameter of glycolytic fibres?

High

11

Relative ability to resist fatigue of glycolytic fibres

Bad

12

Where is smooth muscle found in the body?

- Airways
- Sphincters
- GI tract

13

What is smooth muscle controlled by?

- ANS

14

Arrangement of actin and myosin in smooth muscle?

- Diagonally

15

How are actin and myosin anchored to membranes in cardiac muscles?

Dense bodies

16

What does calcium bind to when it is released from the sarcoplasmic reticulum in smooth muscle?

Calmodulin

17

What does calmodulin bind to?

Myosin light chain kinase

18

What is the function of myosin light chain kinase?

Phosphorylates myosin using ATP

19

What enzyme allows relaxation?

Myosin light chain phosphatase

20

How does myosin light chain phosphatase work?

Dephosphorylates the myosin cross bridges, causing them to unbind

21

What does the action of myosin light chain kinase allow in regards to contraction in smooth muscle?

Sustained contraction

22

Why does the action of myosin light chain phosphatase allow a longer contraction?

Less ATP is used in the contraction on a whole