Photosynthesis and cellular respiration both include water in their summary reactions. Which statement correctly identifies the role of water in these two processes?
Drinking Water / Wellhead Protection | City of Prior Lake, MN
a
Cellular respiration uses water and releases oxygen, while photosynthesis uses oxygen and releases water.
b
Photosynthesis and cellular respiration both use water to help release oxygen.
c
Photosynthesis and cellular respiration both use oxygen and release water.
d
Cellular respiration uses oxygen and releases water, while photosynthesis uses water and releases oxygen.
d
d
Cellular respiration uses oxygen and releases water, while photosynthesis uses water and releases oxygen.
To determine the correct statement, let's break down the processes of photosynthesis and cellular respiration.
1. Photosynthesis:
Photosynthesis is the process by which plants, algae, and some bacteria convert sunlight, carbon dioxide, and water into glucose (energy) and oxygen. The summary equation for photosynthesis is:
6CO2 + 6H2O + light energy → C6H12O6 + 6O2
The role of water in photosynthesis is providing the hydrogen source for the production of glucose. Water molecules split during the light-dependent reactions, releasing oxygen as a byproduct and providing electrons and protons (H+) for the production of NADPH, an energy carrier molecule.
2. Cellular respiration:
Cellular respiration is the process by which cells break down glucose and oxygen to produce energy (ATP), carbon dioxide, and water. The summary equation for cellular respiration is:
C6H12O6 + 6O2 → 6CO2 + 6H2O + ATP
The role of water in cellular respiration is as a byproduct. During the final step of cellular respiration, water is formed when electrons from glucose combine with oxygen.
Now let's evaluate the statements:
a) Cellular respiration uses water and releases oxygen, while photosynthesis uses oxygen and releases water.
This statement is incorrect. Photosynthesis uses water and releases oxygen, while cellular respiration uses oxygen and releases water.
b) Photosynthesis and cellular respiration both use water to help release oxygen.
This statement is incorrect. While photosynthesis uses water to release oxygen, cellular respiration does not involve the release of oxygen.
c) Photosynthesis and cellular respiration both use oxygen and release water.
This statement is incorrect. Photosynthesis uses water and releases oxygen, but cellular respiration uses oxygen and releases water.
d) Cellular respiration uses oxygen and releases water, while photosynthesis uses water and releases oxygen.
This statement is correct. Cellular respiration uses oxygen and releases water, while photosynthesis uses water and releases oxygen.
Therefore, the correct statement is d) Cellular respiration uses oxygen and releases water, while photosynthesis uses water and releases oxygen.