Question

What kinds of molecules can be used as metabolic fuel to produce ATP?

A.water, sugars, and amino acids
B.sugars, amino acids, and fatty acids
C.sugars and fatty acids
D.amino acids, fatty acids, and CO₂

Answer 1

Sugars, amino acids, and fatty acids are the types of molecules that can be used as metabolic fuel to produce ATP. They provide energy by being broken down through various metabolic pathways and entering the Krebs cycle. Therefore, the correct option is B.

Step-by-step explanation:

The types of molecules that can be used as metabolic fuel to produce ATP are sugars, amino acids, and fatty acids. These substrates can be metabolized through various pathways to provide energy for cells. Sugars, often in the form of glucose, fructose, or galactose, provide energy through pathways such as glycolysis and the Krebs cycle. In the absence of carbohydrates, fatty acids can be metabolized to generate ATP through β-oxidation and subsequent steps in the Krebs cycle. Amino acids can be converted into metabolic intermediates including pyruvate, acetyl CoA, acetoacetyl CoA, oxaloacetate, and α-ketoglutarate, which enter the Krebs cycle to support ATP production, especially under conditions like starvation.