Write the difference between:
(a) Actin and Myosin
(b) Red and White muscles
(c) Pectoral and Pelvic girdle

Actin

Myosin

1

Actin is a thin contractile protein.

1

Myosin is a thick contractile protein.

2.

It is present in light bands and is called an isotropic band. (I-band)

2

It is present in dark bands and is called an anisotropic band.(A-band)

Red muscle fibre

White muscle fibre

1

Red muscle fibres are thin and smaller in size.

1

White muscle fibres are thick and larger in size.

2

They are red in colour as they contain large amounts of myoglobin.

2

They are white in colour as they contain small amounts of myoglobin

3

They contain numerous mitochondria.

3

They contain less number of mitochondria.

4

They carry out slow and sustained contractions for a long period.

4

They carry out fast work for short duration.

5

They provide energy by aerobic respiration.

5

They provide energy by anaerobic respiration.

Pectoral girdle

Pelvic girdle

1

It is a skeletal support from where the forelimbs of vertebrates are attached.

1

It is a skeletal support form where the hind limbs of vertebrates are attached.

2

It is composed of two

Bones namely, clavicle or collar bones and scapula or shoulder bone.

2

It is composed of three bones, upper ileum, inner pubic, and ischium.