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
B.
genetic drift
Genetic drift is a random change in allele frequencies over the generations. It is brought by chance alone. Gene flow or gene migration is the physical movement of alleles into and out of a population.
The existence within the population of disadvantage alleles in heterozygous genotypes is known as genetic code.
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
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
Product of sexual reproduction generally generates
longer viability of seeds
prolonged dormancy
new genetic combination leading to variation
new genetic combination leading to variation
Which of the following Bt crops is being grown in India by the farmers?
Maize
Cotton
Brinjal
Brinjal
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
The tendency of population to remain in genetic equilibrium may be disturbed by
random mating
lack of migration
lack of mutations
lack of mutations
Advantage of cleistogamy is
higher genetic variability
more vigorous offspring
no dependence on pollinators
no dependence on pollinators
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
