Final answer:
Mitochondrial DNA (mtDNA) is the type of DNA without recombination, with numerous copies in each cell, and inherited solely from the mother. It's crucial in tracking matrilineal heritage and studying human evolutionary history.
Step-by-step explanation:
DNA Without Recombination and Inheritance from the Mother
The subject of the question pertains to a type of DNA in which there is a no recombination, such as crossing-over, b a high number of copies in each cell, unlike the nuclear genome, and c inheritance solely from the mother. This description fits mitochondrial DNA (mtDNA). Unlike nuclear DNA that undergoes recombination and is inherited from both parents, mtDNA is passed down maternally without undergoing recombination, thus maintaining a mostly unaltered sequence from generation to generation. Each cell contains numerous mitochondria, and therefore, multiple copies of mtDNA. Mapping human history using mtDNA has been particularly useful for molecular anthropologists in understanding the matrilineal lineage and identifying the Mitochondrial Eve or mtMRCA.
Roles of DNA
Our cells each contain 23 pairs of chromosomes responsible for our genotype and phenotype, housing between 20,000-25,000 functional genes that code for various traits. However, we also carry mtDNA in the mitochondria inherited from our mothers, providing us with essential genetic information separate from our nuclear genome. This maternal inheritance pattern serves as a powerful tool in tracing genealogy and studying human evolution.