How many different kinds of gametes will be produced by a plant having the genotype AABbCC ?
Which one of the following is an example of polygenic inheritance ?
(1) Flower colour in Mirabilis jalapa
(2) Production of male honey bee
(3) Pod shape in garden pea
(4) Skin colour in humans
In Mendel's experiments with garden pea, round seed shape (RR) was dominant over wrinkled seeds (rr), Yellow cotyledon (YY) was dominant over green cotyledon (yy). What are the expected phenotypes in the F2 generation of the cross RRYY x rryy ?
(1) Only round seeds with green cotyledons
(2) Only wrinkled with yellow cotyledons
(3) Only wrinkled seeds with green cotyledons
(4) Round seeds with yellow cotyledons and wrinkled seeds with yellow cotyledons.
Test cross involves :
(1) crossing between two geneotypes with recessive trait
(2) crossing between two F1 hybrids
(3) crossing thee F1 hybrid with a double recessive genotype
(4) crossing between two genotypes with dominant trait
If a colourblind woman marries a normal visioned man, their sons wil be :
(1) all normal visioned
(2) one-half colourblind and one-half normal
(3) three-fourths colourblind and one-fourth normal
(4) all colourblind
Cri-du-chat syndrome in humans is caused by the :
(1) fertilization of an XX egg by a normal Y-bearing sperm
(2) loss of half of the short arm of chromosome 5
(3) loss of half of the long arm of chromosome 5
(4) trisomy of 21st chromosome.
Sickle cell anaemia has not been eliminated from the African population because :
(1) it is controlled by recessive genes
(b) it is not a fatal disease
(3) it provides immunity against malaria
(4) it is controlled by a dominant genes
Which of the following shows linkage group in coupling phase?
Which pair is incorrect?
(1) Haemophilia - X linked recessive
(2) baldness - X- linked dominance
(3) colour blindness- X linked recessive
(4) antler in deer - sex limited.
A pure breeding pea plant with the dominant phenotype of character A and recessive phenotype of character B was crossed with another pure breeding plant with the recessive phenotype of character A and dominant phenotype character B. Offspring of this cross was crossed with a homozygous recessive for both the characters A and B. The following results were obtained.
22 were phenotypically dominant of A and recessive of B
22 were phenotypically recessive for both A and B
22 were phenotypically recessive for A and dominant for B
22 were phenotypically dominant for both A and B
The results show that
(1) genes A and B are linked
(2) independent segregation of genes A and B
(3) Mendelian dihybrid inheritance
(4) polygenic inheritance.