Fast Muscle Fibers Contain a High Proportion of Myofibrils, Which

question 35

Multiple Choice

Fast muscle fibers contain a high proportion of myofibrils, which allows the fibers to generate high amounts of force. However, this leaves little room in the fibers for other cellular components, including mitochondria. The opposite is true for slow muscle fibers. Does this information support or refute what you know about the fatigue-susceptibility of fast and slow fibers? Why or why not?

• A) It supports it because if fast fibers have less room for mitochondria than slow fibers do, they cannot produce as much ATP and thus are less fatigue-resistant than slow fibers.
• B) It supports it because if fast fibers have less room for mitochondria than slow fibers do, they can produce more ATP than slow fibers and thus are more fatigue-resistant than slow fibers.
• C) It refutes it because if fast fibers have less room for mitochondria than slow fibers do, they can produce more ATP than slow fibers and thus are less fatigue-resistant than slow fibers.
• D) It refutes it because if fast fibers have less room for mitochondria than slow fibers do, they cannot produce as much ATP and thus are more fatigue-resistant than slow fibers.

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Definitions:

Oligopoly

A market structure characterized by a small number of firms that dominate the market, leading to limited competition.

Economic Profit

The difference between total revenue and total cost, including both explicit and implicit costs.

Purely Competitive

A market structure characterized by many buyers and sellers, free entry and exit, and a product for which all sellers offer identical products.

Marginal Cost

The cost added by producing one extra item of a product.