How do the mitochondrion and chloroplast work together?

Mitochondria and chloroplasts are vital organelles enclosed by double membranes. Researchers believe they originated from a process called endosymbiosis. When all life was single-celled, larger eukaryotic cells engulfed smaller cells. Some of these cells were prokaryotes. Instead of being digested, they formed a symbiotic relationship with their host. Then, over time, the host cells became reliant on these engulfed cells for energy and other cellular functions. Throughout generations, the engulfed prokaryotes evolved into mitochondria and chloroplasts. This theory is called the endosymbiotic hypothesis.

Chloroplasts and mitochondria don't directly work together, but they rely on each other for important processes. Chloroplasts produce oxygen and glucose during photosynthesis, which mitochondria need to perform cellular respiration. In turn, mitochondria produce carbon dioxide during cellular respiration, which is essential for plants to carry out photosynthesis.