Muscle Physiology

Question 1

What are the 3 types of muscle?

Like the tissues

Answer 1

1. skeletal
2. cardiac
3. smooth

Question 2

What are the defining characteristics of skeletal muscle?

Answer 2

• attached to bone
• cannot initiate without motor neuron
• striated

Question 3

What are the defining characteristics of cardiac muscle?

Answer 3

• in heart
• branched cells
• visible striations
• spontaneously active

Question 4

What are the defining characteristics of smooth muscle?

Answer 4

• internal structures
• no striations
• spontaneously active

Question 5

What muscle is this?

Answer 5

Skeletal

Question 6

What muscle is this?

Answer 6

Cardiac

Question 7

What muscle is this?

Answer 7

smooth

Question 8

What type of skeletal muscle is this?

Answer 8

Slow twitch

More pink = more oxygen = doesnt fatigue

Question 9

What type of skeletal muscle is this?

Answer 9

Fast twitch

Less pink = Less oxygen = fatigue

Question 10

Why do fast/slow twitch muscle fibres behave differently?

Answer 10

• The ‘pink’ is the myoglobin
• more myoglobin = more O2 stored
• more O2 = less fatigued

Question 11

What is this?

Answer 11

Skeletal muscle

Question 12

What is this?

Answer 12

Tendon

Question 13

What is this?

Answer 13

Connective Tissue

Question 14

What is this?

Answer 14

Nerve and blood vessels

Question 15

What is this?

Answer 15

Bundle of muscle fibres

Question 16

What is this?

Answer 16

A muscle fibre

Question 17

What is this?

Answer 17

Nucleus

Question 18

Where is calcium stored in the muscle fibres?

Answer 18

In the sarcoplasmic reticulum

(SR)

Question 19

What causes the visible striations in muscles?

Answer 19

When thick and thin filament meet

Question 20

What is myofibril?

Answer 20

Long contractile fibres run through muscle cells

Question 21

What is the role of T-tubules?

Answer 21

• “pathway” to deep centre of cell
• Which is where the SR is

Question 22

What is this?

Answer 22

Nucleus

Question 23

What is this?

Answer 23

Sarcoplasmic Retriculum, SR

Question 24

What is this?

Answer 24

Mitrochondria

Question 25

What is this?

Answer 25

Thick and thin filaments

Question 26

What is this?

Answer 26

Myofibril

Question 27

What is this?

Answer 27

T-Tubules

Question 28

What is this?

Answer 28

Sarcolemma

Question 29

What is the result of having more fibrils?

Answer 29

More force and strength

Question 30

What protein makes up thin filaments?

Answer 30

Actin | several g actin monomers

Question 31

What protein makes up thick filaments?

Answer 31

myosin

Question 32

What are the regulatory proteins and their functions?

Answer 32

* Tropomyosin * Troponin They control when muscles contract

Question 33

What are the accessory proteins and their functions?

Answer 33

* Titin * Nebulin They provide elasticity and structure

Question 34

What type of filament is this?

Answer 34

Thick

Question 35

What type of filament is this?

Answer 35

Thin

Question 36

Fill the blank

Answer 36

Myosin

Question 37

What is this?

Answer 37

Actin

Question 38

Whats going on here?

Answer 38

Question 39

What is a sacromere?

Answer 39

Building block of striations

Question 40

What is this?

Answer 40

Sacromere

Question 41

What are the 6 steps that lead to muscle contraction?

Answer 41

1. myosin attached to actin 2. ATP binds to myosin, causing it to move away from actin 3. ATP breaks down to ADP and Pi 4. Myosin attaches to next actin molecule 5. Pi is released, moving the actin molecule forward 6. Myosin releases ADP and resumes step (1)

Question 42

What is the role of tropomyosin and troponin?

Answer 42

* They prevent muscle contractions when they shouldnt occur * Tropomyosin covers actin, preventing myosin binding

Question 43

What is the role of calcium in muscles?

Answer 43

* Binds to troponin * Which moves tropomyosin out of myosin's way

Question 44

What is an iostonic contraction?

Answer 44

* When muscle contracts and shortens * Moves the load

Question 45

What is an isometric contraction?

Answer 45

* When muslc e contracts but doesnt shorten * Cannot move load

Question 46

Why does a small bicep contraction have a (relatively) larger impact on the hand's movements?

Answer 46

* Bicep inserts near fulcrum so it has lever advantage