NEET BIOLOGY

Detailed explanation-1: -In some muscles myoglobin content is high which gives it 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. They contract for a longer time without muscular fatigue.

Detailed explanation-2: -Red fibers are smaller in size than white fibers, are better supplied with capillaries, and contain more mitochondria. White fibers are equipped better for glycolytic metabolism than are red fibers, which are designed for oxidative metabolism.

Detailed explanation-3: -Slow twitch fibers, also known as type I fibers, contain more mitochondrion and myoglobin molecules than fast twitch fibers (2). Mitochondria are organelles where biochemical processes that generate fuel for the cell through cellular respiration occur.

Detailed explanation-4: -Type I fibers (SO). These fibers have a rich capillary supply, numerous mitochondria and aerobic respiratory enzymes, and a high concentration of myoglobin. Myoglobin is a red pigment, similar to the hemoglobin in red blood cells, that improves the delivery of oxygen to the slow-twitch fibers.