Why Are Slow-Twitch Muscles Dark

question 29

Multiple Choice

Why are slow-twitch muscles dark?

• A) They have many more myofibrils per motor unit than fast-twitch fibers.
• B) They are designed for strength and explosions of energy.
• C) They need less blood than fast-twitch fibers.
• D) They contain myoglobin.
• E) They have fewer mitochondria.

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Definitions:

Unconditioned Response

An innate, spontaneous response to a stimulus that happens without any previous instruction or training.

Conditioned Response

A learned response to a previously neutral stimulus due to conditioning.

Previous Conditioning

The influence of past conditioning experiences on current behavior and learning.

Unconditioned Response

A natural, automatic reaction to a stimulus that occurs without prior learning or conditioning.