Final answer:
The mitochondrion is the cell organelle where cellular respiration occurs, producing ATP, the cell’s main energy-carrying molecule, by utilizing glucose and oxygen, and releasing carbon dioxide as a waste product.
Step-by-step explanation:
The organelle that is the site of cellular respiration is the mitochondrion (mitochondria, plural). Mitochondria are known as the powerhouse or energy factories of both plant and animal cells. They are responsible for the creation of adenosine triphosphate (ATP), which is the main energy-carrying molecule for the cell. ATP stores the cell's short-term energy, which is used in various cellular processes. During cellular respiration, glucose and other nutrients are metabolized to produce ATP while using oxygen and releasing carbon dioxide as a byproduct. Therefore, each exhaled breath contains carbon dioxide generated from these cellular reactions in the mitochondria, indicating their essential role in energy production and respiration.
Mitochondria are oval-shaped, double-membrane organelles that have their own DNA and ribosomes, reflective of their prokaryotic ancestry, supported by the endosymbiotic theory. Their inner membrane folds, known as cristae, and the mitochondrial matrix play distinct roles in cellular respiration, including the Krebs Cycle and the electron transport chain.