If all mitochondrial DNA is from the mother, then how do we get genes that belong to our fathers?

Answer 1

Mitochondria are the powerhouses of the cell. They convert sugar into energy and release CO2 and water. That they live inside our cells is a minor or major miracle. Some very reknown scientists believe that mitochondria were once freeliving, like bacteria. They have their own DNA (genetic blue-print).

Now they live inside the cytoplasm of the cell. Sperm transfers only the other DNA, the blue print of regular genes. The blue print of the mitochondria is strictly programmed by the mother's own mitochondria in her eggs. Pretty special stuff.

Sperm have so many mitochonria because they need to move. They line the end of the whip-like flagella so that the sperm can travel to meet the egg. Once the sperm has fused with the egg, the mitochondria and the flagella no longer have any function and drop away to die. *sniff*

Answer 2

mitochondria are internal cell structures within the cell that have their own DNA. The actual cell DNA is housed in the cell nucleus. A cell and it's mitochondria are like a symbiotic relationship between a host and a parasite, but cells have evolved to use them and pass them along when they reproduce.

We only get our mother mitochondria because at fertilisation the egg is invaded by the sperm and the mitochondria of the egg are passed on to the foetus.

Answer 3

Because the percentage of your DNA that's located in the mitochondria is vanishingly small in comparison with the total. Most of your DNA is in the cell nucleus, half of which you get from your mother and half from your father.