51.

Product of sexual reproduction generally generates

• longer viability of seeds

• prolonged dormancy

• new genetic combination leading to variation

• new genetic combination leading to variation

Advantage of cleistogamy is 

• higher genetic variability

• more vigorous offspring

• no dependence on pollinators

• no dependence on pollinators

Monoecious plant of Chara shows occurrence of 

• antheridiophore and archengoniophore on the same point

• stamen and carpel on the same plant

• upper antheridium and lower oogonium on the same plant

• upper antheridium and lower oogonium on the same plant

Perisperm differs from endosperms in 

• being a haploid  tissue

• having no reserve food

• being a diploid tissue

• being a diploid tissue

Which of the following statements is not true of two genes that show 50% recombination frequency?

• the genes may be on different chromosomes

• the genes are tightly linked

• the genes show independent assortment

• the genes show independent assortment

Variation in gene frequencies within populations can occur by chance rather than by natural selection. This is referred to as

• genetic flow

• genetic drift

• random mating

• random mating

If two persons with 'AB' blood group marry and have sufficiently a large number of children, these children could be classified as 'A' blood group in 1:2:1 ratio. The modern technique of protein electrophoresis reveals the presence of both 'A' and 'B' type proteins in 'AB' blood group individuals. This is an example of 

• codominance

• incomplete dominance

• partial dominance

• partial dominance

The process by which organisms with different evolutionary history evolve similar to a common environmental challenge is called 

• natural selection

• convergent evolution

• non-random evolution

• non-random evolution

The tendency of population to remain in genetic equilibrium may be disturbed by

• random mating

• lack of migration

• lack of mutations

• lack of mutations

Which of the following Bt crops is being grown in India by the farmers?

• Maize

• Cotton

• Brinjal

• Brinjal