Which statement best describes the interdependence of photosynthesis and cellular respiration? A. The reactants of photosynthesis are sugar and oxygen to be used in cellular respiration B. The products of photosynthesis are carbon dioxide and water to be used in cellular respiration C. The reactants of photosynthesis are the products of cellular respiration D. The products are the same as the products of cellular respiration
The Correct Answer and Explanation is:
Correct Answer: C. The reactants of photosynthesis are the products of cellular respiration
Explanation:
Photosynthesis and cellular respiration are two fundamental biological processes that are closely interdependent, forming a biological cycle that sustains life on Earth. Photosynthesis occurs in the chloroplasts of plant cells, while cellular respiration takes place in the mitochondria of both plant and animal cells.
In photosynthesis, plants use sunlight as an energy source to convert carbon dioxide (CO₂) from the atmosphere and water (H₂O) from the soil into glucose (C₆H₁₂O₆) and oxygen (O₂). This process stores solar energy in the chemical bonds of glucose. The general equation for photosynthesis is:
6CO₂ + 6H₂O + light energy → C₆H₁₂O₆ + 6O₂
On the other hand, cellular respiration is the process by which cells break down glucose in the presence of oxygen to release energy in the form of adenosine triphosphate (ATP). This energy is used to power various cellular activities. The byproducts of this process are carbon dioxide and water. The general equation for cellular respiration is essentially the reverse of photosynthesis:
C₆H₁₂O₆ + 6O₂ → 6CO₂ + 6H₂O + ATP (energy)
This reciprocal relationship illustrates their interdependence. The products of photosynthesis—glucose and oxygen—are the exact reactants needed for cellular respiration. Likewise, the products of cellular respiration—carbon dioxide and water—are the reactants needed for photosynthesis. This creates a continuous cycle that maintains atmospheric oxygen and carbon dioxide levels and provides energy for life.
Thus, the correct description of their interdependence is that the reactants of photosynthesis are the products of cellular respiration, and vice versa, highlighting a tightly connected energy and matter cycle within ecosystems.
