Question

Which is not true for red fibres?

Answer 1

Incorrect statement

Statement D

Amount of sarcoplasmic reticulum is high.

Elaboration

Skeletal muscles are composed of long cylindrical fibres known as muscle fibres. These muscle fibres are of two types– red muscle fibres and white muscle fibres.

White muscle fibres undergo faster contractions as compared to red muscle fibres. The requirement for calcium for muscle contraction is higher for white muscle fibres.

Sarcoplasmic reticulum is a network of endoplasmic reticulum present in muscle fibres. It is a storehouse of calcium which is essential for muscle contraction. In order to fulfil the needs of calcium by white muscle fibres for faster contraction, they have higher sarcoplasmic reticulum as compared to red muscle fibres.

Hence, statement D is incorrect.

Final answer: (D) Amount of sarcoplasmic reticulum is high.