The main reason why the testes are suspended within the scrotum is to provide cooler temperature for the testes and make it fertile for penetrating the egg. The Scrotum may contract or lengthen depending on the temperature of its surrounding.
Answer:
x y
x8 x8x x8y
x8 x8x x8y
The results of the punnet square show that:
They will not have a son who will be colour blind.
They will not have a daughter who is colour blind.
All the daughters born will be carriers of red- green colour blindness.
The genotype of the two parents will be:
Genotype of mother: x8,x8
Genotype of father: x, Y
The only independent variable in this experiment is the amount of nitrogen Sarah uses. All of the other variables are dependent on other factor and processes, but Sarah controls the amount of nitrogen that she uses for each plant.