Assertion:  Muscle contains a red coloured oxygen storing pigment called myoglobin.

Reason:  Some of the muscles possess very less quantity of myoglobin and therefore, appear pale or whitish. These are the White fibres.

Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion.

The correct answer is Option (2)- Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion.

Muscle contains a red coloured oxygen storing pigment called myoglobin. Myoglobin content is high in some of the muscles which gives a reddish appearance. Such muscles are called the Red fibres. These muscles also contain plenty of mitochondria which can utilise the large amount of oxygen stored in them for ATP production. These muscles, therefore, can also be called aerobic muscles. On the other hand, some of the muscles possess very less quantity of myoglobin and therefore, appear pale or whitish. These are the White fibres. Number of mitochondria are also few in them, but the amount of sarcoplasmic reticulum is high. They depend on anaerobic process for energy.