The answer is B. they embody the idea of descent with modification.
From what i know, in sickle cell anemia the blood is lack of oxygen.
The haemoglobin run from the blood cell because reacted with nitric oxide, and so thats why the shape of the blood change into sickle-shaped like.
<span>Intrinsic factor is a glycoprotein principally secreted by the parietal cells of the stomach. This secretion is needed to produce mature erythrocytes. Its secretion is governed by the same biochemical processes that regulate acid secretion and its action is to assist in the absorption of vitamin B12.</span>
Out of the animals listed, calves are most genetically similar to humans.
<span>The sun's energy reaches the earth as :
1) Thermal Energy
2) Light Energy
Hope this helps!</span>
