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Which type of muscle fiber has a large number of capillaries?

A) Type I (Slow-twitch)

B) Type IIa (Fast-twitch oxidative)

C) Type IIb (Fast-twitch glycolytic)

D) Type III (Intermediate)

User DIGI Byte
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Final answer:

Slow-twitch muscle fibers have a large number of capillaries, while fast-twitch muscle fibers have fewer capillaries.

Step-by-step explanation:

Skeletal muscle fibers can be divided into two types: slow-twitch (or type I) muscle fibers and fast-twitch (or type II) muscle fibers. Slow-twitch fibers, also known as Type I fibers, are dense with capillaries and rich in mitochondria and myoglobin. They can carry more oxygen and sustain aerobic activity. On the other hand, fast-twitch fibers, also known as Type II fibers, contain fewer capillaries and mitochondria and less myoglobin. They can contract rapidly and powerfully but fatigue quickly.

User Coanor
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