The first three are the same as those found in DNA, but in RNA thymine is replaced by uracil as the base complementary to adenine. This base is also a pyrimidine and is very similar to thymine. Uracil is energetically less expensive to produce than thymine, which may account for its use in RNA.
Human and the natural ones can change the ecosystem
Answer:
Crossing over is a biological occurrence that happens during meiosis when the paired homologs, or chromosomes of the same type, are lined up. Hope this helps :)
Explanation:
<span>Proliferation of lymphocytes occurs immediately after activation, as well as the encounter of antigen. First, these antigen are bound, after which activation begins. Activation immediately leads to proliferation, as well as differentiation. Proliferation is an increase in the number of something, in this case, in the number of lymphocytes, or white blood cells. </span>