If both parents are carriers for thalassaemia, which is an autosomal recessive disorder, what are the chances of pregnancy resulting in an affected child?
(3) No chance
If 'A' represents the dominant gene and 'a' represents its recessive allele, which of the following would be the most likely result in the first generation offspring when Aa is crossed with aa ?
(1) All will exhibit dominant phenotype.
(2) All will exhibit recessive phenotype.
(3) Dominant and recessive phenotypes will be 50% each.
(4) Dominant phenotype will be 75%.
In rabbits, the gene for grey fur (G) is dominant over that for black fur (g). In a litter, if 50% rabbits are grey, then the possible parental cross combination is
(1) GG X Gg
(2) GG X GG
(3) gg X gg
(4) Gg X gg.
Barr Body is found in the cytoplasm during
(1) interphase in cell of female mammal
(2) interphase in cell of male mammal
(3) prophase in cell of female mammal
(4) prophase in cell of male mammal.
Which of the following occurs due to monosomy of sex chromosome?
(1) Down's syndrome
(2) Turner's syndrome
(4) Sickle cell anaemia
Which of the following is true for a recessive disease in family A and B?
(1) In family A, both the parents are homozygous recessive.
(2) In family B, both the parents are homozygous dominant.
(3) In family B, both the parents are heterozygous recessive.
(4) In family A, both the parents are heterozygous recessive.
Which of the following is correct ?
(1) Henking discovered the small Y-chromosome.
(2) Drosophila also shows XX-XY sex determination like human.
(3) Birds have ZZ-ZW sex determination, where females are ZZ and males are ZW.
(4) Grasshoppers show XX-XY sex determination.
Percentage of recombination between A and B is 9%, A and C is 17%, B and C is 26%, then the arrangement of genes is
Which of the following conditions represents a case of co-dominance genes?
(1) A gene expresses itself, suppressing the phenotypic effect of its alleles.
(2) Genes that are similar in phenotypic effect when present separately, but when together interact to produce a different trait.
(3) Alleles, both of which interact to produce a trait, which may or may not resemble either of the parental types.
(4) Alleles, each of which produces an independent effect in a heterozygous condition.
How many genome types are present in a typical green plants cell?
(1) More than Five
(2) More than Ten