Some individuals with blood group $A$ may inherit the genes for blonde hair, while other individuals with blood group $A$ may inherit the gene for brown hair. This can be best explained by the principle of

The phenotypic ratio of $3:1$ proves which of the following?

Which one of the following can be explained on the basis of Mendel's Law of Dominance?
$A$. Out of one pair of factors one is dominant and the other is recessive.
$B$. Alleles do not show any expression and both the characters appear as such in $F_2$ generation.
$C$. Factors occur in pairs in normal diploid plants.
$D$. The discrete unit controlling a particular character is called factor.
$E$. The expression of only one of the parental characters is found in a monohybrid cross.
Choose the correct answer from the options given below:

The law of segregation of characters is also called the law of purity of gametes because

Which of the following traits shows transmission from a carrier female to male progeny?

What is the cross between the progeny of $F_1$ and the homozygous recessive parent called? How is it useful?