Mammalian red blood cells are biconcave which increases the amount of surface area through which oxygen can diffuse. this is an example of

Mammalian red blood cells contain hemoglobin as its primary unit for oxygen and carbon dioxide transportation. In order to increase the efficiency of transport (increase the amount of oxygen and carbon dioxide transported per red blood cell), the red blood cells' structure are designed to be biconcave. This efficient structure of the red blood cells increases it function compared to a spherical red blood cell (low surface area, i.e. hereditary spherocytosis). This is an example of the relationship between structure and function of the red blood cells. Also, the biconcave shape of the red blood cell makes it more resilient to early destruction in the small capillaries and the spleen (since the spleen is mostly responsible for red blood cell turnover, which is every 120 days). 

The answer would be c, white eyes are homozygous recessive. in the early 1900s, morgan conducted several experiments with vinegar  flies (drosophila). one  sample revealed an anomaly: a  white-eyed, single male fly. he attempted to breed this fly with the typical red-eyed females. the offspring were all red-eyed. using flies from this new generation (brother-sister pairs)  produced some red-eyed and a few white-eyed flies. the white-eyed were all male. in later experiments, he was able to produce white-eyed females. this proved that white eyes are not lethal to either sex (ruling out a and b). since the percentage of white eyes to red eyes is so low, white eyes are not a dominant trait. it would be a recessive trait.