Video Transcript
Which of the following statements
correctly relates energy to catabolic and anabolic reactions? Anabolic reactions require energy
to form new molecules, whereas catabolic reactions release energy as molecules are
broken down. Or catabolic reactions require
energy to form new molecules, whereas anabolic reactions release energy as molecules
are broken down.
Let’s investigate some of the key
terms in the question to help us figure out how to answer it. Catabolic and anabolic reactions
are both types of metabolic reactions that occur within the cells of living
organisms to help them survive. Let’s take a look at catabolic
reactions first. Catabolic reactions break down
large molecules into smaller units. The breaking of bonds in the large
molecule releases energy, which can be used in the cell for other reactions. For example, proteins are broken
down into amino acids in our digestive system. This is an example of a catabolic
reaction, as a large molecule is forming several smaller molecules and the process
overall releases energy.
Anabolic reactions construct larger
molecules from individual units, and this process requires energy to form the bonds
between these subunits. For example, these amino acids are
being joined together to form a large protein, and it requires an input of
energy. The energy is used to form these
bonds between the individual amino acids. So, this is an anabolic
reaction. Therefore, our correct answer is
that anabolic reactions require energy to form new molecules, whereas catabolic
reactions release energy as molecules are broken down.
