Question

List three ways that mtDNA differs from DNA in a cell's nucleus.

Short answer

Mitochondrial DNA (mtDNA) differs from nuclear DNA in several key ways: 1) mtDNA is inherited from the mother, while nuclear DNA is derived from both parents. 2) mtDNA is circular and localized in the mitochondria, while nuclear DNA is linear and located in the cellular nucleus. 3) mtDNA codes for a limited number of proteins related to energy production, while nuclear DNA controls most of an organism's genetic traits.

Step-by-step solution

Origin of the DNA

Mitochondrial DNA is inherited solely from the mother. This is because the mitochondria in the sperm are destroyed during fertilization. In contrast, nuclear DNA is a mix of both parents' genes.

Physical Structure

Another difference is their structures. Nuclear DNA is linear while mitochondrial DNA is circular, similar to bacterial DNA. Nuclear DNA resides within the cell nucleus, while mtDNA is found in the mitochondria, an organelle in the cell.

Roles and replication

Lastly, mtDNA and nuclear DNA have different roles and replication processes. Nuclear DNA holds the majority of genetic information and is responsible for coding most of an organism's traits. mtDNA, on the other hand, is responsible for coding a small number of proteins needed for the mitochondria's main function, which is to produce energy.