Mitochondria are often referred to as the “powerhouses of the cell” because they play a crucial role in cellular respiration. This process involves breaking down nutrients to produce energy in the form of adenosine triphosphate (ATP), which is the primary energy currency used by cells.

Here’s a breakdown of the mitochondria’s role in cellular respiration:

1. Glycolysis: This initial stage occurs in the cytoplasm and involves the breakdown of glucose into pyruvate, producing a small amount of ATP.
2. Pyruvate Oxidation: Pyruvate is transported into the mitochondria, where it is converted into acetyl-CoA.
3. Citric Acid Cycle (Krebs Cycle): Acetyl-CoA enters the citric acid cycle, a series of chemical reactions that release energy and produce carbon dioxide.
4. Oxidative Phosphorylation: This final stage occurs in the inner mitochondrial membrane. Electrons are transferred through a series of proteins, creating a proton gradient. As protons flow back across the membrane, ATP is produced.

Overall, mitochondria are responsible for generating the majority of ATP in eukaryotic cells, which is essential for various cellular processes, including muscle contraction, protein synthesis, and nerve impulse transmission.