Question

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

Answer 1

(a) Actin and Myosin

	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.	2	It is present in dark bands and is called an anisotropic band.

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(b) Red and White muscles

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 a smaller 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.

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(c) Pectoral and Pelvic girdle

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.