Question

Mitochondrial DNA is highly conserved across organisms and is used to map phylogeny of organisms – why would this be important for organisms to have such high fidelity here? What kinds of mechanisms might there be in place to maintain this?

Answer 1

Mitochondria ,unless specifically stained,are not easily visible under the microscope. The number of mitochondria per cell is variable depending on the physiological activity of the cells,In terms of shape and size also considerable degree of variability is observed.Typically it is sausage-shaped or cylindrical having a diameter of 0.2-1.0 ųm and length 1.0-4.1 ųm.Each mitochondrion is a double membrane -bound structure with the outer membrane and the inner membrane dividing its lumen distinctly into two aqueous compartments,the inner compartment is called matrix.The outer membrane forms the continuous limiting boundary of the organelle.The inner membrane forms a number of infolding called the cristae towards the matrix,The cristae increase the surface area.The two membranes have their own specific enzymes associated with The mitochondrial function.Mitochondria are the sites of aerobic respiration.They produce cellular energy in the form of ATP,hence they are cs pled power house of the cell.The matrix also possesses single circular DNA molecules, a few RNA molecules,ribosomes 70s and the components required for the synthesis of proteins.The mitochondria divide by fission.

• It was first observed byKolliker in 1859 in strained muscles,and named by Benda in 1897.
• Matrix contains circular DNA molecules and 55s ribosomes.
• It controls the level of water and other materials in cell
• Recycles and decompose proteins,fats and carbohydrates, and forms urea.
• Myocardial muscles cells have numerous large mitochondria called sacrosomes.
• Time lapse microcinematography of living cells reveal the mobile and plastic nature of mitochondria.
• Attacheddd to the inner membranes are repeated units of stalked particles called oxysomes or F0 F1 particles.They are meant for APT synthesis and oxidation or oxidative phosphorylation.

Mitochondrial DNA importance :

It offers so many benefits to determine phylogeny organisms.

1. Mitochondrial DNA is trasfered from mother to child
2. There is no recombination is observed in inherited DNA.
3. Mutation rate is very
4. High amounts of mitochondrial DNA are gathered for sequencing.
5. It is used to segregate people into halogroups.