Muscles

Question 1

Which type of muscle does not contain striations?

Answer 1

Smooth muscle

Question 2

What are striations in skeletal muscle caused by?

Answer 2

Sarcomeres

Question 3

Where are calcium ions released from?

Answer 3

Sarcoplasmic reticulum

Question 4

What do the calcium ions bind to after being released from the sarcoplasmic reticulum?

Answer 4

Troponin

Question 5

What are the 2 antagonistic groups of muscles that movement of a limb relies upon?

Answer 5

Flexors

Extensors

Question 6

What is the name of the blocking protein that prevents muscle contraction?

Answer 6

Tropomyosin

Question 7

When tropomyosin is removed, what is then exposed?

Answer 7

The actin binding sites

Question 8

What is the definition of an isotonic twitch?

Answer 8

A contraction with shortening length

Question 9

What is the definition of an isometric twitch?

Answer 9

A contraction with constant length

Question 10

Tetanus is a state of what?

Answer 10

Extended contraction via the summation of APs

Question 11

During tetanus, tropomyosin is always held in what state?

Answer 11

Non-blocking state

Question 12

Fatigue is caused by what?

Answer 12

Repeated muscle stimulation

Question 13

What are the two types of skeletal muscle fibre?

Answer 13

Oxidative fibres

Glycolytic fibres

Question 14

Which type of skeletal muscle fibre has more mitochondria?

Answer 14

Oxidative fibres

Question 15

Smooth muscle exists in what type of organs?

Answer 15

Hollow organs

GI tract

Question 16

What does calcium bind to in smooth muscle contraction?

Answer 16

Calmodulin

Question 17

Relaxation in smooth muscle is brought about by what?

Answer 17

Myosin light chain phosphatase

Question 18

Why can contraction be held for longer in smooth muscle?

Answer 18

Due to the low rate of consumption of ATP

Question 19

What is skeletal muscle attached to bone by?

Answer 19

Tendons

Question 20

After injury, cells in muscles are replaced by what?

Answer 20

Satelitte cells

Question 21

What does striated muscle have repeating units of?

Answer 21

Sarcomeres

Question 22

What are the two main filaments of sarcomeres?

Answer 22

Myosin and actin

Question 23

What is the name of the thick filament of a sarcomere?

Answer 23

Myosin

Question 24

During contraction of a striated muscle, Which band/zone is reduced?

Answer 24

H band/zone

Question 25

What are motor units made of?

Answer 25

Motor neurones and muscle fibres

Question 26

What is the latent period?

Answer 26

The time before the excitation contraction starts

Question 27

What is the energy source required for contraction?

Answer 27

ATP

Question 28

What does muscle fatigue prevent?

Answer 28

Muscles using up vast amounts of ATP

Question 29

What are the 3 types of muscle fibre?

Answer 29

Slow oxidative Fast oxidative Fast glycolytic

Question 30

Which fibres are activated first?

Answer 30

Slow oxidative

Question 31

Which nervous system innervates smooth muscle?

Answer 31

ANS

Question 32

What is the main difference in the arrangements of filaments in smooth muscle compared to skeletal muscle?

Answer 32

The filaments are arranged diagonally in smooth muscle

Question 33

How does myosin light chain phosphatase relax smooth muscle?

Answer 33

Dephosphorylates X-bridges

Question 34

In single unit muscle cells, cells are linked by what?

Answer 34

Gap junctions

Question 35

Multiunit muscle cells dont respond to what?

Answer 35

Stretch