As their name suggests, mitochondria and nuclear DNA are both types of DNA. Though they are both DNA, there are many differences between them. One of those differences is their location. Mitochondria DNA is located in the cell's mitochondria, while the nuclear DNA is found in the nucleus.
Another difference between them is the shape of them. Mitochondria DNA is in a circular shape, while nuclear DNA is in a double helix. Along with the shape, the DNA's offer differ when it comes to the inheritance. Nuclear DNA will come from both parents, while Mitochondria DNA will only come from the mother.
It can be confusing to know the difference between mitochondrial DNA and nuclear DNA. The main difference is where the DNA can be found. Obviously, for nuclear DNA, the DNA can be found in the nucleus of the cell. For the mitochondrial DNA, the DNA can be found in the mitochondria of the cell.
Another main difference is the number of genes that can be found in the DNA. Nuclear DNA can come with 20,000 to 25,000 genes. This is actually quite a lot, especially when you would compare it with the number of genes that can be found in mitochondrial DNA, which is only 37.