Chloroplasts are the site of photosynthesis in which cells?

• A. Animal cells
• B. Plant and algae cells
• C. Bacterial cells
• D. Fungal cells

Answer: (B)

Chloroplasts are the site of photosynthesis in plant and algae cells. These organelles contain chlorophyll and the internal membrane system where the light-dependent reactions take place, producing ATP and NADPH that power the fixation of CO2 into sugars in the surrounding stroma. Because chloroplasts are characteristic of plants and many algae, these cells can convert light energy into chemical energy. In contrast, animal and fungal cells lack chloroplasts and cannot photosynthesize. Some bacteria can perform photosynthesis, but they do so without chloroplasts, using different internal membranes. So plant and algae cells are the ones with chloroplasts performing photosynthesis.