In a cross between genotypes showing recessive epistasis,the $F_2$ phenotypic ratio will be .....

Variation refers to .......

Match List-$I$ with List-$II$ :

List-$I$ (Type of Inheritance)	List-$II$ (Example)
$A$. Incomplete dominance	$I$. Blood groups in human
$B$. Co-dominance	$II$. Flower colour in Antirrhinum
$C$. Pleiotropy	$III$. Skin colour in human
$D$. Polygenic inheritance	$IV$. Phenylketonuria

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What is the number of chromosomes in the gamete cells of a housefly?

Match List-$I$ with List-$II$:

List-$I$	List-$II$
$(a)$ Gain or loss of nitrogen base	$(i)$ Aneuploidy
$(b)$ Gain or loss of segment of $DNA$	$(ii)$ Frame shift
$(c)$ Gain or loss of whole set of chromosome	$(iii)$ Euploidy
$(d)$ Gain or loss of one chromosome	$(iv)$ Chromosomal aberration

$ABO$ blood type in man is an example of
$A$. Pleiotropy
$B$. Incomplete dominance
$C$. Co-dominance
$D$. Multiple allelism
Select the code for the correct answer from the options given below.