The answers are Stabilizing selection, directional selection and disruptive selection respectively.
<h3><u>Explanation</u>:</h3>In case of a population of a species, there exists both the homozygous alleles as well as the hybrid of the two characters. This leads to co existence of both hybrids and homozygotes together in a population.
Now because of the natural selection, there remains some characteristics in either homozygotes or in hybrids which gets special advantages over other. So nature selects the preferred race and the number of those individuals in the population increase.
If number of one of the homozygotes increase, then it's the directional selection.
If the number of the hybrids increase, then its Stabilizing selection.
And if both the homozygotes are selected, then it's divergent selection.
Answer:
When both _signal molecules_ are in their receptor sites, the molecules form a dimer (two molecules joined together). ATP is converted to ADP and the _phosphate group_ gets attached to the tyrosine molecules. The addition of the _ relay proteins_ causes a cascade of cellular responses.
Explanation:
I have added explanation as image form so it will help you understand more easily.
