Question

1. brad makes the claim that since steak is a food that is high in protein, then a person who includes a lot of steak in their diet would have a higher proportion of protein in their bodys tissues compared to someone who doesnt eat steak. he conducts some research to support his idea.

macromolecules in steak
brad collects data from online databases to organize into the chart shown in figure 1. the data breaks down the percentages of fats, protein, and carbohydrates found in a 1 oz cut of beef tenderloin.
to see if his claim is correct, brad conducts a study. he recruits subjects to agree to follow a strict diet that is either high - protein (in the form of steak) or a balanced diet. his data is shown in table 1.
brad is surprised to find that the increase in protein found in the body was not more pronounced in the high - protein subjects. in addition, he expected to see a drop in the composition of carbohydrates, but these levels remained the same across the test groups.
which of the following best explains the “unexpected outcomes” in brad’s experiment?
a. the macromolecules the body gets in your food are broken down and rebuilt into other macromolecules in the body tissues.
b. a high - protein diet results in a higher fat metabolism, which is why this subjects fat content was lower than the other subject.
c. fats are stored in specialized body cells called lipocytes, which are consumed as an alternative energy source by the body if no food is available.
d. carbohydrates are only stored in small amounts in the body, and we must consume large amounts of them to stay energized.

Explanation:

• Option A: When food is consumed, macromolecules (like proteins, fats, carbohydrates) are digested. Proteins are broken down into amino acids, which can be used to build other proteins or even be converted into other macromolecules (e.g., amino acids can be used in energy - production pathways). So, just because a diet is high in protein (steak), it doesn't directly mean body tissues will have a much higher protein proportion as the body processes and re - uses these macromolecules. This explains why the increase in body protein wasn't very pronounced. Also, for carbohydrates, since they are broken down and can be used in various metabolic processes (not just stored as is), their levels remaining the same can be explained as they are part of a dynamic metabolic pool.
• Option B: The question is about protein and carbohydrate levels. This option focuses on fat metabolism and fat content, which is not relevant to explaining the unexpected protein and carbohydrate results.
• Option C: This option is about fat storage and its role as an alternative energy source. It has no bearing on the protein and carbohydrate levels in the body as observed in the experiment.
• Option D: While it is true that carbohydrates are stored in small amounts (glycogen in liver and muscles), it doesn't explain why the carbohydrate levels in the body didn't change in response to the diet (since the diet had a similar small amount of carbohydrates). The key is the metabolic processing (as in option A) rather than just storage amount.

Answer:

A. The macromolecules the body gets in your food are broken down and rebuilt into other macromolecules in the body tissues.