Muscle

Question 1

Where are the nuclei in skeletal muscle?

Answer 1

Peripheral

Question 2

What are the three types of muscle?

Answer 2

Skeletal
Cardiac
Smooth

Question 3

What types of skeletal muscle fibres can be found in skeletal muscle?

Answer 3

Red, white, intermediate (pink)

Question 4

What is a striated muscle cell also known as?

Answer 4

A muscle fibre

Question 5

In a muscle fibre what does the epimysium surround?

Answer 5

The fascicles

Question 6

What surrounds the fascicles?

Answer 6

The perimysium

Question 7

What surrounds the muscle fibres?

Answer 7

Endomysium

Question 8

What are the two types of filaments that make up myofibrils?

Answer 8

Myosin and Actin

Question 9

What shape does the actin filament form?

Answer 9

A helix

Question 10

What other compounds are involved with the actin filament?

Answer 10

Tropomyosin

Troponin

Question 11

What molecule binds to troponin to start the sliding filament mechanism?

Answer 11

Calcium

Question 12

List 4 properties of cardiac muscle

Answer 12

Striated
Central nuclei
Intercalated discs
Branching

Question 13

What shape are smooth muscle cells?

Answer 13

Spindle-shaped

Question 14

Where is the nucleus positioned in a smooth muscle cell?

Answer 14

Centrally

Question 15

Why is less ATP needed in smooth muscle?

Answer 15

Less and slower contraction

Question 16

Where can smooth muscle be found?

Answer 16

Walls of vascular structures
Walls of the gut
Respiratory tract
Genitourinary system

Question 17

What are a myoepithelial cells?

Answer 17

A radiating network of cells that surround secretory units of exocrine glands to assist excretion

Question 18

What is a myofibroblast?

Answer 18

Produce a collagenous matrix at sites of wound healing. Allow wounds to contract.

Question 19

How does skeletal muscle repair itself?

Answer 19

Tissue regenerates by satellite cells undergoing hyperplasia after muscle injury.

Question 20

How does skeletal muscle get bigger?

Answer 20

Satellite cells fuse with existing muscle mass

Question 21

What type of muscle cell cannot regenerate?

Answer 21

Cardiac muscle

Question 22

What type of muscle cell can regenerate via mitosis?

Answer 22

Smooth muscle cells

Question 23

What is the technical term for muscle wasting?

Answer 23

Atrophy

Question 24

Describe 3 changes that happens to muscle after exercise

Answer 24

Sarcoplasmic reticulum swells
Number of mitochondria increases
Width of Z band increases
T tubule system increases in density

Question 25

What effect does weightlifting have on muscles?

Answer 25

Increases muscle mass and strength by hypertrophy

Question 26

What effect does jogging have on muscles?

Answer 26

Increases endurance- more mitochondrial proteins made for more ATP production. Oxygen is utilised better

Question 27

Name 3 groups of people who will experience muscle atrophy

Answer 27

Elderly
Bed rest patients
Astronauts
Limbs in casts

Question 28

Briefly describe what happens at a neuromuscular junction

Answer 28

Acetylcholine released by the presynaptic membrane
Na+ enters the post-synaptic membrane and depolarises the cell
Ca2+ is released from the sarcoplasmic reticulum
The muscle contracts

Question 29

What happens at the neuromuscular end plate in a sufferer of Myasthenia Gravis?

Answer 29

The acetylcholine receptors are destroyed by the autoimmune system. The folds in the membrane are lost and the synaptic cleft widens

Question 30

List 3 symptoms of Myasthenia Gravis

Answer 30

Fatigue
Falling
Drooping eyelids
Double vision

Question 31

What is the most common muscular dystrophy?

Answer 31

Duchenne Muscular Distrophy

Question 32

What does the protein dystrophin do?

Answer 32

Connects muscle fibres to the surrounding extracellular matrix through the cell membrane.