Definition of Mitochondria
The mitochondrion is a double-membraned organelle that can be found in the cytoplasm of the cells of nearly all Eukaryotic organisms. This little energy-making centre breaks down the nutrients and releases chemical energy in the form of ATP, or adenosine triphosphate, in the cell. In addition to making ATP, the mitochondria control cell growth and death, send signals to other cells, and make heat. It plays a major role in cellular respiration. ATP is also made in the body through a process called anaerobic fermentation, which does not happen in mitochondria. For mitochondria to make ATP, they must have oxygen and glucose. This process makes more energy than anaerobic fermentation.
Diagram of Mitochondria
Figure 1: Structure and function of mitochondria with diagram.
Structure of Mitochondria
Animal mitochondria are round or oval and are held together by two membranes. Phospholipid bilayers and proteins are what make up these membranes. In animal cells, the different parts of mitochondria are:
Outer Membrane: The inner organelles are protected and held securely in place by the outer membrane. Protein and a phospholipid bilayer make up its constituent parts. Enzymes that perform a wide range of functions are located in the cell’s outer membrane. Ions, ATP, ADP, and so on are able to freely travel through this membrane since it is also macromolecule permeable.
Inter Membrane Space: Intermembrane space is the space between the outside membrane and the inside membrane. Small molecules like ions and sugars are also in this space. This is because the outer membrane that surrounds it lets these molecules pass through.
Inner Membrane: Proteins with different functions make up the inner membrane of the mitochondria. It also has the enzymes that speed up the processes that are needed to make ATP. The inner membrane of the mitochondria can let oxygen, carbon dioxide, and water through. The main place where ATP is made is in the inner membrane of the mitochondria. The inner mitochondrial membrane has several folds in it called Cristae, to increase the surface area.
Cristae: The inner membrane of mitochondria is folded into several folds. These folds are called cristae. The cristae increase the surface area inside the mitochondrial membrane to generate ATP molecules efficiently. The larger the surface, the more the space to carry out cell functions. The surface of the cristae has exosomes attached to it, which aids the osmosis of ions. A lot of chemical reactions occur in the inner membrane on the surface of the cristae.
Matrix: The space in the inner membrane apart from the cristae in the Matrix. It is fluidic and contains proteins, ribosomes, enzymes, tRNA, and genomic DNA. Due to the presence of genetic material, the Mitochondrial Matrix can synthesize its RNA and proteins. The synthesis of ATP would be incomplete without the enzymes of the matrix which aid the most important chemical cycles.
Function of Mitochondria
The main thing that mitochondria do is make energy. It is the place where the nutrients go through a chemical process that turns them into ATP. The other big job that mitochondria do is to make sure that the cell’s metabolism works. Through cellular metabolism, three major processes are carried: 1. Conversion of food into energy, 2. Conversion of food into molecules that are essential for the body like proteins, carbohydrates, etc, 3. Eliminations of the wastes.
Mitochondria are also needed for cells to grow and divide. When an organ has to work too hard to do a certain task, the mitochondria in that organ multiply on their own to help the organ do its job better. It is also a key part of apoptosis, or the death of cells. During apoptosis, a cell doesn’t die because it was damage. Instead, a series of chemical reactions kills the cell.
It is also responsible for maintaining homeostasis by producing heat. It occurred as a result of mitochondrial uncoupling, in which the re-entry of protons into the matrix does not result in ATP production. It accumulates calcium ions, which facilitates cell signalling. Mitochondria influence cell signalling because free calcium affects a number of chemical events within the cell. Mitochondria also control cell differentiation, cell senescence, and the cessation of cell division.
FAQs on Structure and function of Mitochondria.
Mitochondria are organelles with a membrane that are found in the cytoplasm of all eukaryotic cells. They are accountable for the production of Adenosine triphosphate (ATP), the cell’s primary energy currency.
The main job of mitochondria is to make energy through a process called oxidative phosphorylation. Besides this, it is in charge of controlling how the cell’s metabolism works. It also helps cells grow and make more copies of themselves. In liver cells, mitochondria also get rid of ammonia. Also, it is a key part of apoptosis.
Mitochondria are located in the cytoplasm of cells along with other organelles of the cell.
Your heart, liver, muscles, and brain all rely heavily on mitochondria for their energy needs. Mitochondria account for 40% of heart muscle cells and 25% of liver cells, respectively.
No, Without mitochondria, the organelles that power the majority of human cells, life would be impossible.