The main roles of mitochondria lie in energy conversion, participation in the tricarboxylic acid cycle, storage of calcium ions, regulation of cell proliferation and cellular metabolism, and synthesis of cholesterol and certain hemoglobins, etc., which are described below.
1. Energy conversion: mitochondria are the site of oxidative metabolism in eukaryotes, and are the place where sugars, fats and amino acids are finally oxidized to release energy.
2. Participation in the tricarboxylic acid cycle: each molecule of pyruvate generated in glycolysis will be actively transported across the mitochondrial membrane. After entering the mitochondrial matrix, pyruvate is oxidized to form acetyl coenzyme A, the primary substrate of the tricarboxylic acid cycle.
3. Storage of calcium ions: mitochondria can store calcium ions, and can work synergistically with structures such as the endoplasmic reticulum and the extracellular matrix, thus controlling the dynamic balance of calcium ion concentration in the cell. Regulates membrane potential and controls programmed cell death.
4. Mitochondria are also involved in the regulation of cell proliferation and cell metabolism.
5. Mitochondria are also involved in the synthesis of cholesterol and certain hemoglobin functions.