Final answer:
The purpose of photosynthesis is to store the sun's energy in food molecules, specifically glucose. Photosynthesis involves the conversion of light energy into chemical energy, which is used to produce glucose during the Calvin cycle. This process contributes to the carbon cycle. The correct option is C. To store the sun's energy in food molecules.
Step-by-step explanation:
The purpose of photosynthesis is best identified as C. To store the sun's energy in food molecules. During photosynthesis, plants, algae, and certain bacteria convert light energy from the sun into chemical energy, which is stored in the bonds of glucose molecules. Glucose is then used as a stable form of energy storage that can be turned into various other forms, such as starches or cellulose in plant cell walls. This stored energy can later be harnessed through the process of cellular respiration where the chemical energy from the glucose is converted back into ATP, the energy currency the cell uses for various functions.
Photosynthesis occurs in the chloroplasts of plant cells and involves two main stages: the light-dependent reactions and the Calvin cycle (also known as the light-independent reactions). During the light-dependent reactions, sunlight is absorbed by chlorophyll and converted to chemical energy in the form of ATP and NADPH. These energy carriers are then used in the Calvin cycle to synthesize glucose from carbon dioxide and water.
It is crucial to understand that while ATP is a part of the photosynthesis process, its role is to supply the immediate energy for the synthesis of glucose. The ATP produced during the light-dependent reactions is not the primary long-term storage form of the sun's energy; rather, the glucose molecules are. The overall process of photosynthesis contributes to the carbon cycle by transforming carbon dioxide into oxygen and organic carbon compounds, thus sustaining life on Earth.