Question

a scientist is examining the role of an element found in fats and carbohydrates of living things. this element makes up 65% of human body mass. which statement describes the element he is studying? he is studying oxygen, which can also be found in proteins. he is studying oxygen, which is the most abundant element in the atmosphere. he is studying nitrogen, which can also be found in proteins. he is studying nitrogen, which is the most abundant element in the atmosphere.

Explanation:

Step1: Analyze the element in fats and carbohydrates

Fats and carbohydrates contain carbon, hydrogen, and oxygen.

Step2: Consider the element making up 65% of human body mass

Oxygen is a major component of the human body (about 65% by mass). Nitrogen is not the element making up 65% of human body mass.

Step3: Check the presence in proteins

Oxygen is present in proteins (in the carboxyl group, hydroxyl groups etc.). Nitrogen is also in proteins (in the amino group), but since the element in question is the one in fats/carbohydrates and 65% of body mass (which is oxygen), we focus on oxygen's presence in proteins.

Step4: Analyze the most abundant element in the atmosphere

The most abundant element in the atmosphere is nitrogen (about 78%), not oxygen (about 21%). So the statement about oxygen being the most abundant in the atmosphere is wrong.

So the correct answer is that he is studying oxygen, which can also be found in proteins.

Answer:

He is studying oxygen, which can also be found in proteins.