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Flashcards in Muscles 1 Deck (22)
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1
Q

What do muscles allow us to do?

A

Generate force and movement

Express and regulate ourselves

2
Q

What are the two types of muscles?

A

Striated - skeletal and cardiac

Smooth - blood vessels, airways

3
Q

Skeletal muscles are very ______. The form in ______ from ______ myoblasts and increase fibre size during growth.

A

Long, utero, mononucleate

4
Q

How are the connective tissue muscles connected to bones?

A

By tendons

5
Q

What proof is there that chains in the muscle fibres are very strong and compressed?

A

Nuclei found on the outside of cells.

6
Q

Why are deeply penetrating blood vessels necessary?

A

Muscle fibres need a thick blood supply.

7
Q

What are z-lines?

A

Border of the repeating unit.

8
Q

What is another name for repeating unit?

A

Sarcomere

9
Q

What is a guiding proteins function?

A

Ensures myosin can always slide in between 2 actin filaments.

10
Q

Define actin.

A

Arranged in a double helix and each monomer is a binding site.

11
Q

Define myosin.

A

2 actin binding sites on head, 2 ATP sites and a heavy chain and a light chain.

12
Q

What is the process of the cross bridge cycle?

A
Cross bridges bind to actin
Calcium concentration increases
ADP and Pi break off of myosin
Cross bridge has a conformational change
ATP binds to myosin head
Cause myosin to detach 
ATP hydrolyses
Repeat
13
Q

What does troponin, tropomyosin and calcium do in the cross bridge cycle?

A

Tropomyosin partially covers myosin binding site
Cooperative block with troponin
Calcium binds to troponin
Troponin alters shape, pulling tropomyosin away
Removal of calcium will reblock the myosin sites

14
Q

Where is calcium stored?

A

Sarcoplasmic reticulum.

15
Q

Define motor unit.

A

Motor neurones and muscle fibres.

16
Q

Define tension.

A

Force exerted by muscle

17
Q

Define load.

A

Force exerted on muscle.

18
Q

Define isometric

A

Contraction with constant length

19
Q

Define iostenic

A

Contraction with shortening length

20
Q

Define lengthening

A

Contraction with increasing length

21
Q

What are twitch contractions?

A

Single action potentials

22
Q

Define latent period.

A

Time before excitation contraction.