Chloroplasts are organelles that contain chlorophyll, a green pigment that absorbs light energy from the sun. This light energy is used to convert carbon dioxide and water into glucose, a sugar that plants use for energy. Chloroplasts are found in plant cells and some algae cells.
Mitochondria are organelles that produce energy for the cell. They contain a special membrane that allows oxygen to be used to break down glucose and other molecules to produce ATP, a molecule that cells use for energy. Mitochondria are found in all eukaryotic cells.
Both chloroplasts and mitochondria have their own DNA, which is different from the DNA in the nucleus of the cell. This suggests that these organelles were once independent organisms that lived in a symbiotic relationship with other cells. Over time, these organelles became integrated into the eukaryotic cell and became essential for its survival.
