mitochondria: The power houses of the cell

Mitochondria are membrane-bound organelles known as the "powerhouses" of the cell. They generate energy in the form of ATP (adenosine triphosphate) through the process of cellular respiration. Mitochondria have their own DNA and are involved in other critical cellular functions, including regulation of the cell cycle, apoptosis (programmed cell death), and calcium storage. Their ability to produce energy is essential for cell survival and function.

1. MI T OCHONDRIA S.Nahidha begum II.Msc.Microbiology Sacred Heart College

2. MI T OCHONDRIA The mitochondria (Greek. "mitos" - thread; "chondros" - granule) are the centres for the Cellular respiration and Energy metabolism. Mitochondria was first described by a German Pathologist named Richard Altmann in 1890. Mitochondria are regarded as the "Power houses of the cell". Mitochondria are rod-like or filamentous bodies. It is present in eukaryotes and absent in prokaryotes

3. MI T OCHONDRIA The Eukaryotic cells contains 800 to 2500 Mitochondria per cell. The size of the mitochondria is 0.2 to 0.8 µm in diameter and 0.5 to 1.0 µm in l ength. The shape of the mitochondria in Non - static. Major function of Mitochondria ATP Generation through Electron Transport Chain (ETC)

4. c Mitochondria consist of 5 i m portant parts. They a r e O u t er Mitoc h o n drial Membrane Inner Mitoc h o n drial Me m brane Inter Membrane Space Cr i s tae Matrix Mi t o c hondr i a

5. a) Outer Mitochondrial Me m brane Outer mitochondria membrane is present in the outer surface of the Mitochondria. It consist of Phospholipids and considerable amount of Cholesterol. The Outer mitochondrial membrane is permeable to all molecules

6. Inner mitochondria membrane is pre se nt in the inner s urface of the mitochondria. It consists of Phospholipid - Cardiolipin and rich in Protein s. The Inner Mitochondrial Membrane i s impermeable to polar and ionic substance. It is permeable to Pyruvate , ADP , ATP, Succinate , a - ketoglutarate , Malate , Citrate and Ions (Hydrogen , Pota ss ium and Sodium). Inner mitochondrial membrane i s larger than Ou ter mitochondrial membrane. b) Inner Mitoc h ondrial Me m brane

7. The space between the Outer mitochondrial membrane and Inner mitochondrial membrane is called "Inner membrane space". c ) I n ter Me m brane Space

8. d ) C ristae The inner mitochondrial membrane is highly folded and forms the finger like structure called Cristae".

9. e ) Matrix The space inside the Inner mitochondrial membrane is called "Matrix". Matrix contains Circular DNA, Ribosomes , Granules and ATP Synthase. It is rich in the enzymes responsible for the Citric acid cycle, ­ oxidation of fatty acids and Oxidation of amino acids.

10. F u ncti o ns of Mitochondria ATP Generation through Electron Transport Chain. Regulates the Metabolic activity of the cell. Promotes the growth of new cells and cell multiplication. Plays an important role in Apoptosis or Programmed cell death. Helps in maintaining an adequate concentration of Calcium ions within the compartments of the cell. Also involved in various cellular activities like Cellular differentiation , Cell signaling, Cell senescence, Controlling the cell cycle and also in cell growth.