Question

DNA can be compared from closely related species to determine when two species last shared a common ancestor.

True or false

Answer 1

True

Organisms that share similar genetic sequences tend to be more closely related than those that do not.

Similar DNA reflects shared evolutionary ancestry. At the most basic level, all living organisms share:

• The same genetic material (DNA)
• The same, or highly similar, genetic codes
• The same basic process of gene expression (transcription and translation)
• · The same molecular building blocks, such as amino acids

            These shared features suggest that all living things are descended from a common ancestor and that this ancestor had DNA as its genetic material, used the genetic code, and expressed its genes by transcription and translation.