If egg and sperm form first cell of baby, then why does mtDNA comes from mother only?

Question

If egg and sperm form first cell of baby, then why does mtDNA comes from mother only?

In: Biology

Answer 1

The sperm only carries the father’s DNA, it doesn’t contribute any of the organelles that are used to express that DNA and run the cell. The egg is what contains all the necessary apparatus for the running of the initial cell that splits into the embryo, as well as containing the mother’s DNA. The mitochondria are one of these organelles, and they actually contain their own specific DNA just for making more mitochondria, and that DNA is kept separate from the DNA that is in the nucleus of the cell. So the reason mitochondrial DNA only comes from the mother is because only the mother provides mitochondria in the egg cell.