Video Transcript
Which of the following statements
about metabolism is incorrect? (A) Catabolism includes all of the
metabolic reactions that break down large biological molecules into smaller
ones. (B) Anabolism includes all of the
metabolic reactions that build large biological molecules from smaller ones. (C) A smaller person will always
have a faster metabolism than a larger person. (D) Metabolism is the sum of all
chemical reactions within a cell or organism.
This question is asking us about
metabolism, which refers to all the chemical reactions that occur within the
body. Since this refers to answer choice
(D), we can eliminate this option because it is a correct statement about
metabolism.
There are two types of metabolic
reactions, catabolic and anabolic. Catabolic reactions are reactions
that break down large molecules into smaller units to release energy. This is indicated as answer choice
(A), so we can eliminate this option.
This energy is in the form of a
molecule called ATP, or adenosine triphosphate. ATP is the universal energy
currency of our body. And all the energy from the food we
eat, such as from carbohydrates, can be stored in molecules of ATP. Anabolic reactions, on the other
hand, are the reversed set of reactions where small molecules can be assembled into
larger molecules. So we can eliminate answer choice
(B).
These reactions require energy, and
this energy comes from the ATP that was generated during catabolic reactions. We can see that the remaining
answer choice states that a smaller person will always have a faster metabolism than
a larger person. This is false, since the rate of
metabolism is dependent mostly on genetics, and both small and large people can have
fast metabolisms.
So the option that is incorrect is
given by answer choice (C). A smaller person will always have a
faster metabolism than a larger person.
