Question

A cell gains energy by combining glucose with oxygen in a series of chemical reactions. The products are carbon dioxide and water. What is the source of this energy?

A. the forces that attract protons and neutrons within carbon nuclei
B. the breaking of chemical bonds within the molecules of the reactants
C. the breaking of chemical bonds within the molecules of the products
D. the kinetic energy of oxygen molecules
E. strong forces within the atomic nuclei of the reactants

Answer 1

The energy in cellular respiration comes from the breaking of chemical bonds in glucose molecules, which releases stored chemical energy that the cell captures as ATP.

Step-by-step explanation:

The energy that a cell gains when combining glucose with oxygen in a series of chemical reactions is derived from the breaking of chemical bonds within the molecules of the reactants. When a cell performs cellular respiration, it releases the chemical energy stored within the bonds of glucose (C6H12O6).

This process can be summarized by the chemical equation, C6H12O6 + 6 O2 → 6 CO2 + 6 H2O + Energy. As the glucose molecule is broken down, energy is released from the breaking of its chemical bonds and is captured in the form of ATP (adenosine triphosphate), which cells use to perform various functions. This cellular respiration is a catabolic reaction where energy is released when complex molecules like glucose are broken down.