Question

question 18
what purpose do protein molecules serve in the body?
a. proteins help build muscle tissue.
b. proteins help humans produce oxygen.
c. proteins prevent muscles from absorbing oxygen.
d. proteins slow down the production of carbon dioxide.

Explanation:

To determine the correct answer, we analyze each option:

• Option A: Proteins are essential for building and repairing muscle tissue. Muscle tissue is largely composed of proteins like actin and myosin, so this is a valid function of proteins.
• Option B: Humans do not produce oxygen; oxygen is inhaled from the atmosphere. Proteins have no role in oxygen production.
• Option C: Muscles need to absorb nutrients (including oxygen for respiration) to function. Proteins do not prevent muscle oxygen absorption; in fact, they support processes that use oxygen.
• Option D: Carbon dioxide production is a result of cellular respiration. Proteins do not slow down its production; they are involved in metabolic processes that may contribute to energy production (and thus CO₂ production as a byproduct in some cases).

So, the correct option is A as it accurately describes a function of protein molecules in the body.

Answer:

A. Proteins help build muscle tissue.