The important things to remember are that chromosomes as well as genes occur in ...$A$.... The two alleles of a gene pair are located on homologous sites on ...$B$... chromosomes
Choose the correct choice for $A$ and $B$
For the expression of traits genes provide only the potentiality and the environment provides the opportunity. Comment on the veracity of the statement.
Define and design a test - cross?
Mendel obtained recessive character in $F_{2}$ by ...$A$... the ...$B$... plants. Here $A$ and $B$ refers to
Change in single base pair