Light Energy Capture

Photosynthesis begins when chlorophyll molecules in plant leaves absorb sunlight. These pigments, concentrated in chloroplasts, capture light energy primarily from red and blue wavelengths. The absorbed energy excites electrons in chlorophyll molecules, initiating a series of chemical reactions. This process occurs in the thylakoid membranes of chloroplasts, where specialized protein complexes convert light energy into chemical energy.

Carbon Fixation

The energy captured from light drives the conversion of carbon dioxide and water into glucose. This process, called the Calvin cycle, occurs in the stroma of chloroplasts. Carbon dioxide enters leaves through tiny pores called stomata, while roots absorb water. The resulting glucose serves as an energy source for plant growth and development, while oxygen is released as a byproduct.

Energy Storage

Plants convert excess glucose into starch for storage in roots, stems, and leaves. Some glucose transforms into cellulose for cell wall construction or other complex molecules needed for growth. This stored energy not only supports plant survival during darkness but also provides food for other organisms. The process of photosynthesis produces nearly all the oxygen in Earth's atmosphere and forms the basis of most food chains.Shutdown123