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Mitochondria are the cell's power producers. They convert energy into forms that are usable by the cell. Located in the cytoplasm, they are the sites of cellular respiration which ultimately generates fuel for the cell's activities. Mitochondria are also involved in other cell processes such as cell division and growth, as well as cell death.

They convert oxygen and nutrients into adenosine triphosphate (ATP). ATP is the chemical energy "currency" of the cell that powers the cell's metabolic activities. This process is called aerobic respiration and is the reason animals breathe oxygen.

Mitochondria are bounded by a double membrane. Each of these membranes is a phospholipid bilayer with embedded proteins. The outermost membrane is smooth while the inner membrane has many folds. These folds are called cristae. The folds enhance the "productivity" of cellular respiration by increasing the available surface area. The double membranes divide the mitochondrion into two distinct parts: the intermembrane space and the mitochondrial matrix. The intermembrane space is the narrow part between the two membranes while the mitochondrial matrix is the part enclosed by the innermost membrane. Several of the steps in cellular respiration occur in the matrix due to its high concentration of enzymes. Mitochondria are semi-autonomous in that they are only partially dependent on the cell to replicate and grow. They have their own DNA, ribosomes and can make their own proteins. Similar to bacteria, mitochondria have circular DNA and replicate by a reproductive process called fission. The inner membrane selects over what materials are allowed through it and it is known that active transport mechanisms involving translocase enzymes are responsible for the movement of ADP and ATP across it.

Mitochondria use respiration to brake down high energy molecules such as sugars and store that energy as ATP (produced from ADP & a phosphate) The raw materials used to generate ATP are the foods that we eat, or tissues within the body that are broken down in a process called catabolism. The breaking down of food into simpler molecules such as carbohydrates, fats, and protein is called metabolism. These molecules are then transferred into the mitochondria, where further processing occurs. The reactions within the mitochondria produce specific molecules that can have their electrical charges separated within the inner mitochondrial membrane. These charged molecules are processed within the five electron transport chain complexes to finally combine with oxygen to make ATP. The process of the charged substances combining with oxygen is called oxidation, while the chemical reaction making ATP is called phosphorylation. The overall process is called oxidative phosphorylation. The product produced by this process is ATP. Using Oxygen to Release Energy

Mitochondria are used in cellular respiration. The matrix is filled with water and proteins (enzymes). Those proteins take food molecules and combine them with oxygen. The mitochondria are the only place in the cell where oxygen can be combined with the food molecules. After the oxygen is added, the material can be digested. They are working organelles that keep the cell full of energy. On the ethical implications of mitochondrial DNA analysis:

Mitochondrial DNA analysis is a somewhat different type of DNA analysis compared to other techniques used today. It generally works well on samples that are unable to be analysed through numerous other techniques. So is There a Risk From Complete mtDNA Sequencing ?

Yes, and the risk from having a complete mtDNA sequencing begins when a person first thinks about ordering the test - as for the first time it is possible to have a test performed for genealogical purposes that can actually affect the person's well being.

Before agreeing to mtDNA sequencing it is important to consider just how one might be affected by the results. Fortunately, for about 90-95% of...
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