Which organelle is the site of aerobic respiration and ATP synthesis?

Explanation

The Krebs cycle runs in the mitochondrial matrix and the electron transport chain sits in the inner membrane, where the proton gradient drives ATP synthase. The inner membrane is folded into cristae to increase that surface area, which is why heart muscle cells are packed with mitochondria. Lysosomes digest material, and the Golgi and smooth ER handle processing and lipid synthesis.