Acidosis, the pH of a human should be 7.4 and never lower than 7.35
The concave disc shape of red blood cells Maximizes the surface area of the cell , allowing for rapid movement of oxygen or carbon dioxide to and form the hemoglobin within the cell.
A person can only show a recessive trait if both of their parents carried at least one copy of each of the recessive allele. The parents do not need to show the trait, as one copy is not enough to reveal it, but they must both carry it.
Hope this helped!