Glucose is a type of sugar molecule made of carbon, hydrogen, and oxygen. In the body, glucose combines with oxygen to form palmitic acid, water, and carbon dioxide. Palmitic acid is a fatty acid found in both plants and animals.

Question

The image below models this reaction. In the actual reaction, more than one of each type of molecule may be used or produced.

glucose (C6H12O6) and oxygen (O2) react to become palmitic acid (C16H32O2), carbon dioxide (CO2), and water (H2O)

What must be true of the actual reaction but is not shown in the model?
A.
The number of glucose molecules at the beginning of the reaction must equal the number of palmitic acid molecules at the end of the reaction.
B.
Every glucose molecule joins with another glucose molecule to form a molecule of palmitic acid.
C.
The number of oxygen atoms in the glucose and oxygen must equal the number of oxygen atoms in the palmitic acid, water, and carbon dioxide.
D.
Every carbon atom from the glucose molecule must end up in a molecule of palmitic acid.

Answer 1

In the context of the biochemical reaction where glucose and oxygen are converted into palmitic acid, water, and carbon dioxide, the correct answer is:

C. The number of oxygen atoms in the glucose and oxygen must equal the number of oxygen atoms in the palmitic acid, water, and carbon dioxide.

This is a restatement of the law of conservation of mass, which states that matter cannot be created or destroyed in a chemical reaction. Therefore, the number of atoms of each element must be balanced on both sides of the equation.