During meiosis crossing over occurs at the pachytene stage, when homologous chromosomes are completely paired. At diplotene, when homologs separate, the sites of crossing over become visible as chiasmata, which hold the two homologs of a bivalent tighter until segregation at anaphase.
This is a very good question and the answer to it is option A. The common core set of genes is very similar between all organisms.
This is true because several facts, for example, all living beings on earth share the same gene code: DNA, all of them are based on DNA or RNA, which humans have it too. This was explained by Darwin's evolution theory, we are all descendants of just one single species, and because of that, all species have something in common between them.
That's why there's a possibility that a human gene can correct a defective gene in a yeast cell. Although this could really happen, we are not sure about it, it's a possibility, don't always be sure of something in biology, there's always more to understand and to learn.
Answer:
Using a combination of policy tools prevents the use of mandatory policies.
Explanation:
Friedrich Miescher he discovered DNA and found a substance called nuclein which was present in every cell type he tested.
