Assertion : Phenotypic superiority of hybrid over either of its parents in one or more traits is termed hybrid vigour.
Reason : Suppression of expression of recessive harmful genes occurs in heterozygotes.

Superioority of the hybrid over both the parents in respect of one or more characters.

Assertion: Hybrid vigour is superior over either of its parents. Reason: Hybrid vigour is lost upon inbreeding.

Assertion:Hybrid is superior than either of its parents. Reason:hybrid vigour is lost inbreeding.

Asseration :Hybrid is superior than either of its parents. Reasons : vigour is lost upon inbreeding.

Superiority of hybrids over parents only in vegetative growth not in yield. This phenomenon is termed as …………. .

Assertion : Frequency of crossing overs is higher then the observed frequency of recombinatin of traits in the offsprings. Reason : More than one cross over many occur simultaneously between the same chromatids.