Here's why:

* Photosynthesis: This process uses sunlight, carbon dioxide, and water to produce glucose (sugar) and oxygen. This primarily happens in chloroplasts, which are organelles found in plant cells (and some algae).

* Respiration: This process breaks down glucose to release energy (ATP) for the cell's activities. This occurs in the mitochondria, another organelle present in plant cells (and all other eukaryotic cells).

Therefore, both respiration and photosynthesis take place in some plant cells, specifically those containing both chloroplasts and mitochondria.