Question

Explain why some muscle is dark and some muscle is pale.

Answer 1

Dark muscle is red because it contains a lot of myoglobin and mitochondria, while pale muscle is white because it has fewer of these components.

Step-by-step explanation:

The color of muscle tissue, whether dark or pale, is determined by the type of muscle fibers present. In general, dark muscle tissue appears red and is called slow twitch muscle or Type-I muscle fibers. These muscles are rich in myoglobin, which helps store oxygen, and mitochondria, which produce energy aerobically. On the other hand, pale muscle tissue appears white and is called fast twitch muscle or Type-II muscle fibers. These muscles have fewer mitochondria and myoglobin, and rely on anaerobic metabolism for energy.