An organelle found in plant and algae cells where photosynthesis occurs.

• A. Vacuole
• B. Endoplasmic Reticulum
• C. Chloroplast
• D. Nucleolus

Answer: (C)

Photosynthesis occurs in chloroplasts, organelles found in plant and many algae cells. Chloroplasts contain chlorophyll, the pigment that captures light energy. Within these organelles, light-dependent reactions on the thylakoid membranes produce ATP and NADPH, which power the Calvin cycle in the stroma to convert carbon dioxide into sugars. This is why plant and algae cells can make their own food using light. A vacuole stores water and maintains turgor pressure but isn’t involved in photosynthesis. The endoplasmic reticulum synthesizes and transports proteins and lipids, not light-driven energy capture. The nucleolus handles ribosomal RNA synthesis inside the nucleus, not photosynthesis.