skeletal muscle Flashcards
1
Q
Name 3 categories of muscle
A
- Skeletal
- Cardiac
- Smooth
2
Q
Give characteristics of muscle fibres
A
- Parallel
- Multinucleated
- Elongated
- Cylindrical
3
Q
What are myofibrils?
A
Contractile elements of muscle fibres
4
Q
What is the area between 2 Z lines called?
A
Sarcomere
5
Q
What is the functional unit of skeletal muscle?
A
sarcomere
6
Q
Comment of sarcomere geometry
A
- Thin filaments form a hexagon around thick filament
- Thick filaments triangulate a central thin filament
- A single thick filament can cross bridge to 6 thin filaments
7
Q
Name the thick filament protein
A
Myosin
8
Q
Name the thin filament protein
A
Actin
9
Q
How many strands do actin filaments form?
A
2
10
Q
What structure do actin molecules form?
A
Actin helix
11
Q
What do tropomyosin and troponin do?
A
Lie along groove of actin helix
12
Q
How many neutrons supply a muscle fibre?
A
1 or more
13
Q
What is called a motor unit?
A
1 motor neuron plus all muscle fibres it innervates
