Muscle Structure and Function

Question 1

What are the three types of muscles?

Answer 1

1. Skeletal Muscle
2. Cardiac Muscle
3. Smooth Muscle

Question 2

Skeletal Muscle Components

Answer 2

i. Striated: symmetrical lines and also has many nuclei
ii. Voluntary: you choose when to contract it when performing activities
iii. 600 skeletal muscles making up 40-50% of a normal person’s body weight
1. ex. Involuntary: breathing, postural support and shivering
2. Pain reflex: touching something that is hot, brain sense and withdraws it
3. Heat protection: getting heat from exercise

Question 3

Cardiac Muscle Components

Answer 3

i. Interconnected (electrically coupled)

ii. Involuntary

Question 4

Smooth Muscle Components

Answer 4

i. Non-striated
ii. Involuntary
- Found in the digestive system, urinatory, etc

Question 5

Structure of Skeletal Muscle

Answer 5

• composed of fasciculi that are bunched together
• within each fascicle, there are bundles of individual muscle fibres
• ## muscle fibres are composed of myofibrilsmuscle➡️fascicle➡️muscle fibre➡️myofibril

Question 6

Skeletal Muscle Parts

Answer 6

Epimysium- outer
Perimysium- middle
Endomysium- inside
Fibrils: a collection of myosin and actin cells
- A single myosin head can pull in 6 actins