Yao Is 45 Years Old

question 89

Multiple Choice

Yao is 45 years old.How has the maximum vital capacity of his lungs changed from when he was 25?

• A)It has decreased by about 5 percent.
• B)It has decreased by about 20 percent.
• C)It has remained constant.
• D)It has increased by about 10 percent.

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Definitions:

Muscle Contraction

The process where muscle fibers actively shorten to produce movement or generate force in response to a stimulus.

Active Sites

Areas on enzymes that serve as the site for substrate molecules to attach and participate in a chemical reaction.

Calcium Ion Blocking

The process or action of inhibiting the movement of calcium ions through channels, affecting muscle contraction and other physiological activities.

Sarcoplasmic Reticulum

A specialized type of smooth endoplasmic reticulum in muscle cells, involved in the regulation of calcium ions concentration.