Question

Starting with glucose \(\left(\mathrm{C}_{6} \mathrm{H}_{12} \mathrm{O}_{6}\right),\) write the overall equation for glucose breakdown in the presence of oxygen, compare this to the overall equation for photosynthesis, and explain how the energy components of the equations differ.

Short answer

The overall equation for glucose breakdown (cellular respiration) in the presence of oxygen is: \[\mathrm{C}_{6} \mathrm{H}_{12} \mathrm{O}_{6} + 6 \mathrm{O}_{2} \rightarrow 6 \mathrm{H}_{2} \mathrm{O} + 6 \mathrm{CO}_{2} + \text{Energy}\] In contrast, the overall equation for photosynthesis is: \[6 \mathrm{H}_{2} \mathrm{O} + 6 \mathrm{CO}_{2} + \text{Energy (light)} \rightarrow \mathrm{C}_{6} \mathrm{H}_{12} \mathrm{O}_{6} + 6 \mathrm{O}_{2}\] These equations are essentially reverse processes. The main difference in their energy components is that cellular respiration releases energy by breaking down glucose, while photosynthesis stores energy by synthesizing glucose and oxygen using light energy, water, and carbon dioxide.

Step-by-step solution

Identify the overall equation for glucose breakdown in the presence of oxygen

The overall equation for the breakdown of glucose (cellular respiration) in the presence of oxygen is called cellular respiration, which can be written as: \[\mathrm{C}_{6} \mathrm{H}_{12} \mathrm{O}_{6} + 6 \mathrm{O}_{2} \rightarrow 6 \mathrm{H}_{2} \mathrm{O} + 6 \mathrm{CO}_{2} + \text{Energy}\] This equation represents the breakdown of glucose into carbon dioxide and water, releasing energy in the process.

Identify the overall equation for photosynthesis

Photosynthesis is the process by which plants and other organisms convert sunlight, carbon dioxide, and water into glucose and oxygen. The overall equation for photosynthesis can be written as: \[6 \mathrm{H}_{2} \mathrm{O} + 6 \mathrm{CO}_{2} + \text{Energy (light)} \rightarrow \mathrm{C}_{6} \mathrm{H}_{12} \mathrm{O}_{6} + 6 \mathrm{O}_{2}\] This equation represents the synthesis of glucose and oxygen from water and carbon dioxide, using light energy.

Compare the two equations

When comparing the two equations, we can observe that they are essentially the reverse of each other. Cellular respiration breaks down glucose and produces carbon dioxide, water, and energy, while photosynthesis uses carbon dioxide, water, and light energy to produce glucose and oxygen. Cellular Respiration: \[\mathrm{C}_{6} \mathrm{H}_{12} \mathrm{O}_{6} + 6 \mathrm{O}_{2} \rightarrow 6 \mathrm{H}_{2} \mathrm{O} + 6 \mathrm{CO}_{2} + \text{Energy}\] Photosynthesis: \[6 \mathrm{H}_{2} \mathrm{O} + 6 \mathrm{CO}_{2} + \text{Energy (light)} \rightarrow \mathrm{C}_{6} \mathrm{H}_{12} \mathrm{O}_{6} + 6 \mathrm{O}_{2}\]

Explain the difference in energy components

The key difference between the energy components of the two equations lies in the fact that cellular respiration releases energy while photosynthesis stores energy. In cellular respiration, the breakdown of glucose results in the release of energy, which is then utilized by the cells for performing various metabolic activities. The energy is usually stored in the form of ATP (adenosine triphosphate). On the other hand, photosynthesis requires an input of energy in the form of light to convert carbon dioxide and water into glucose and oxygen. This energy is stored in the glucose molecules, which can be later broken down by the cells during cellular respiration to release the stored energy. In summary, cellular respiration and photosynthesis are complementary processes that are involved in the energy transformation within living organisms. While cellular respiration releases energy by breaking down glucose, photosynthesis stores energy by synthesizing glucose and oxygen using light energy, water, and carbon dioxide.