AP BIOLOGY

Detailed explanation-1: -Similarities and differences among biological molecules (e.g., in the DNA sequence of genes) can be used to determine species’ relatedness. Biogeographical patterns provide clues about how species are related to each other.

Detailed explanation-2: -Molecular clocks are used to determine how closely two species are related by calculating the number of differences between the species’ DNA sequences or amino acid sequences. These clocks are sometimes called gene clocks or evolutionary clocks.

Detailed explanation-3: -Scientists can now determine relatedness by comparing the frequency of nucleic acid bases (the G + C content), perform nucleic acid hybridization to determine the degree to which DNA sequences are the same, perform nucleic acid sequencing, or perform other advanced molecular techniques.

Detailed explanation-4: -Molecular homology as evidence of relatedness between species including DNA and amino acid sequences, mtDNA (the molecular clock) and the DNA hybridisation technique.