Answer: Disruptive selection
Explanation:
Disruptive selection is a natural selection method, it is also known as diversify selection.
Disruptive selection occurs when natural selection favors both extremes of continuous variation. Over time, the two extreme variations will become more common and the intermediate states will be less common or lost.
Frost wedging - water expands about 9% after freezing this pushes against the rock and fractures or breaks it open.
thermal expansion - <span>is the tendency of matter to change in shape, area, and volume in response to a change in temperature.</span>
<span>it has to be in living organisms, it has to have a plasma membrane and it has to arise from a previously existing cell.</span>
Answer:
See explanation below
Explanation:
<em>Non-disjunction occur as a result of lack of separation of homologous chromosomes during meiosis. </em>
As a result, the gametes (the daughter cells formed) produced end up having extra or lesser chromosomes as compared to a normal gamete.
When a gamete with extra chromosome fertilizes a normal gamete, the resulting offspring will have an extra chromosome (trisomy condition).
On the other hand, when a gamete with one less chromosome than normal fertilizes a normal gamete, the resulting offspring will have one less chromosome than normal offspring (monosomy condition).
Assuming a chromosome with Aa gene undergoes non disjunction during meiosis, the resulting gametes either contain both A and a chromosome or contain no chromosome at all.
If Aa gamete is fertilized by a normal haploid sperm (a), the resulting zygote will have the genotype Aaa.
If a gamete with no chromosome at all fertilizes a normal haploid sperm, the resulting offspring will have the genotype a.
The correct answer is helper T cells.
<span>The helper T cells are one of the main cells of the adaptive immune system. Their role is to help the activity of other immune cells by releasing T cell cytokines and they are required for almost all adaptive immune responses. The helper T cells activate B cells to secrete antibodies, stimulate macrophages to destroy ingested pathogens, and help in activation of cytotoxic T cells to kill infected target cells.</span>
