Question

Now, for each of the substances below, consider the impact of each substance on cellular respiration.

Substance A’s Effect: Prevents electrons from binding to NAD+. Determine whether this substance would result in weight gain or weight loss. Explain your reasoning.

Substance B’s Effect: Increases the number of protons concentrated in the mitochondria intermembrane compartment Determine whether this substance would result in weight gain or weight loss. Explain your reasoning. The substances described above all interfere with aerobic respiration, requiring oxygen. When your cells run out of oxygen, such as your muscle cells during intense exercise, they can switch to lactic acid fermentation.

Answer 1

Substance A’s Effect: Prevents electrons from binding to NAD+ --à Causes weight loss because the electron transport is uncoupled and the ATP generation is impaired, so more glucose or other energy resources will be metabolized to produce ATP. Thus, the metabolic rate increases and body weight decreases.

Substance B’s Effect: Increases the number of protons concentrated in the mitochondria intermembrane compartment -à Causes weight gain because it favours ATP synthesis and reduced the metabolic rate.