How does the vestigial thumb a frog survive

Why is it important to reduce the number of chromosomes in half when forming gametes for sexual reproduction?

Ineed some everybody. the production of cells during mitosis into specialized function is called: recombination or differentiation

How is ribosomal rna useful as a molecular clock? a. a large portion of the dna ring is not vital to structure or function, allowing it to accumulate neutral mutations. b. its rate of mutation increases over time as organisms continue to evolve and differentiate from each other. c. a slow mutation rate makes it useful for determining evolutionary relationships between ancient species. d. it is only found in select organisms, making it easier to compare relationships between species that have it.