An allele is a/an:

Which of the following did Mendel select for his experiments?

If a cross between pure red and pure white flowered pea plants produces $120$ pea plants,what will be the ratio of the progeny?

Mendel crossed tall and dwarf plants. In the $F_{2}$-generation,the observed ratio was $3: 1$ (tall: short). From this result,he deduced:
$I.$ Law of dominance
$II.$ Law of independent assortment
$III.$ Law of segregation
$IV.$ Incomplete dominance
Choose the correct option.

Which of the following can be used to determine the genotype of an offspring with a dominant phenotype?

$A$ diploid organism is heterozygous for $5$ loci and homozygous for $2$ loci,how many types of gametes can be produced?