How do plants capture and use light in photosynthesis?

Plants capture and use light through a process called photosynthesis, primarily using a pigment called chlorophyll.

Capturing Light Energy

The initial step in photosynthesis is the light-dependent reaction, which occurs within the thylakoid membranes of chloroplasts. This process specifically requires sunlight:

• Chlorophyll's Role: Chlorophyll, a pigment found within the thylakoid membrane, is essential for capturing light energy. This pigment absorbs light waves, specifically from the red and blue parts of the visible light spectrum.

Converting Light Energy to Chemical Energy

Once light energy is absorbed, it is not directly used by the plant; instead, it's converted into chemical energy. Here's how that occurs:

• Energy Conversion: According to the reference, "The chlorophyll absorbs energy from the light waves, which is converted into chemical energy in the form of the molecules ATP and NADPH."
• ATP and NADPH: These molecules, adenosine triphosphate (ATP) and nicotinamide adenine dinucleotide phosphate (NADPH), are energy-carrying molecules that store the captured light energy in a chemical form.

Using Chemical Energy

These molecules (ATP and NADPH) provide the energy needed for the next phase of photosynthesis, the light-independent reactions or the Calvin cycle, where carbon dioxide is converted into glucose (sugar).

Summary

Essentially, plants use chlorophyll to capture light energy and transform it into usable chemical energy stored in ATP and NADPH. These molecules then drive the synthesis of glucose.