Question

Which of the following is not true for red fibres?

• A. Contains red, oxygen storing pigment
• B. Large number of mitochondria
• C. They are also called aerobic muscles
• D. High number of sarcoplasmic reticulum

Answer 1

The correct option is D High number of sarcoplasmic reticulum

Myoglobin is a red, oxygen storing pigment present in some muscles. Such muscles are therefore called red fibres. They contain a large number of mitochondria hence these muscles are also called aerobic muscles.
In some muscles, there is less amount of myoglobin and therefore they appear pale or whitish. These muscles are known as white fibres. These muscles have less number of mitochondria but have a high amount of sarcoplasmic reticulum.