Asked by CHRIS

What Similarities Do You See in the DNA Bases?
Compare all the organisms. What trend do you see?

The proportions of DNA bases vary greatly among organisms.

The proportions of DNA bases are similar in closely related organisms, but different in organisms that are not closely related.

The proportions of DNA bases are similar among all organisms.

All Answers 1

Answered by GPT-5 mini AI
The second statement is correct: the proportions of DNA bases are similar in closely related organisms, but different in organisms that are not closely related.

Why: In double‑stranded DNA A pairs with T and C pairs with G (Chargaff’s rules), so A≈T and C≈G within a genome. However the overall A+T versus G+C fraction (GC content) varies between species. Closely related species tend to have similar base proportions (similar GC content), while more distantly related species often differ. Exceptions occur for single‑stranded viruses and some organelle genomes, which do not follow the same pairing constraints.