Which cell organelle is primarily involved in photosynthesis?

Which cell organelle is primarily involved in photosynthesis?

• A. Ribosome
• B. Chloroplast
• C. Nucleus
• D. Mitochondrion

Answer: (B)

Photosynthesis happens in chloroplasts, the special energy-harvesting organs of plant cells and some algae. These organelles contain chlorophyll, the pigment that captures light, and their internal membranes form the light-dependent machinery that produces ATP and NADPH. Those energy carriers feed the Calvin cycle in the surrounding stroma, where carbon dioxide is fixed into sugars like glucose. Other organelles have different jobs: ribosomes synthesize proteins, the nucleus stores genetic material, and mitochondria generate ATP through cellular respiration. So the chloroplast is the site where light energy is converted into chemical energy and stored in sugars.

Photosynthesis happens in chloroplasts, the special energy-harvesting organs of plant cells and some algae. These organelles contain chlorophyll, the pigment that captures light, and their internal membranes form the light-dependent machinery that produces ATP and NADPH. Those energy carriers feed the Calvin cycle in the surrounding stroma, where carbon dioxide is fixed into sugars like glucose. Other organelles have different jobs: ribosomes synthesize proteins, the nucleus stores genetic material, and mitochondria generate ATP through cellular respiration. So the chloroplast is the site where light energy is converted into chemical energy and stored in sugars.