Which statement describes red muscle?

• A. Red muscle is mostly slow fibers, dark, rich blood supply, large amounts of myoglobin.
• B. White muscle is mostly slow fibers, dark.
• C. Red muscle is formed from non-muscle tissue.
• D. Smooth muscle is striated.

Answer: (A)

Red muscle fibers are slow-twitch, oxidative fibers. They appear dark because they contain a high amount of myoglobin, which stores and transports oxygen, and they have a rich network of blood vessels. This combination supports steady, endurance-type activity and makes the muscle fatigue-resistant. The statement fits this picture: red muscle is dominated by slow fibers, has a dark color, and is well supplied with blood and myoglobin. In contrast, white muscle describes fast-twitch fibers with less myoglobin and fewer capillaries, and smooth muscle is not striated. Red muscle is skeletal tissue, not formed from non-muscle tissue.