When a plant of $F_1$ generation is crossed with homozygous dominant parents,it is known as

Read the following statements carefully $:-$
$(a)$ Linkage is physical association of genes on a chromosome.
$(b)$ In $Drosophila$, genes of body colour and eye colour are tightly linked on $X$-chromosome.
$(c)$ In honey bee a fertilised egg develops as a male $(drone)$.
$(d)$ In grasshopper males have only one $X$-chromosome besides the autosomes.
$(e)$ $Drosophila$ can complete their life cycle in about two months.
Choose the correct option having all correct options.

Which mammals have more yolk than cytoplasm in their eggs?

In bread wheat,the chromosome number is:

Read the following statements and identify the correct ones.
$(1)$ Linkage and recombination were first understood in $Lathyrus$ $odoratus$.
$(2)$ Mendel's work was rediscovered by Correns,Tschermak,and de Vries,which was published in $1900$.
$(3)$ $T.H.$ Morgan is considered the father of experimental genetics.
$(4)$ $A$ child born to parents with thalassemia major can be affected by thalassemia.
$(5)$ In birds,the female is homogametic and the male is heterogametic.

Differences in twins suggest