Como podrías justificar que el ser humano y el ratón tienen aproximadamente 80% de similitud en la información genética

Both species are mammals and therefore they share genome regions and gene families that are conserved in the course of evolution.

Explanation:

Synteny enables to identify conserved genome regions between species by aligning their DNA sequences. For example, the human and chimpanzee genomes share about 95-98% of synteny (sequence similarity) in their DNA sequences. In this case, a whole-genome sequence similarity of 80 % is evidence that both species are relatively closely related and share a near common ancestor. Indeed, it is expected that the most part of the remaining 20% represents mutations associated with the fixation of neutral alleles (i.e., neutral mutations) and therefore have no evolutionary meaning.

hydroxyl -oh

alcohols, always polar, can form hydrogen bonds with h2o molecules

carboxyl -cooh  

cargoxylic acids, has acidic properties which is a source of hydrogen ions, found in cells in ionized for with a charge of oh-1

carbonyl > co

ketone if within skeleton, aldehyde if group is at the end of skeleton, k & a may be structural isomers, it determines 2 sugars (ketose & aldose)

amino -nh2

amines, acts as a base, it can pick up h+ ions from surrounding solution, ionized with charge of 1+

methyl ch2

addition to rna/dna affects and gene expression

phosphate -opo3 ²⁻

organic phosphates, contributes to negative charge to, molecule that it is a part of, and potential to react with h20

sulfhydryl -sh

thiols, cross-linking stabilize the protein, and it is structure