Consider the cross AaBb x AaBb. If the alleles for both genes exhibit complete dominance, what genotypic ratio is expected in the resulting offspring?
1. 1:1:1:1
2. 9:3:3:1
3. 3:6:3:1:2:1
4. 1:2:1:2:4:2:1:2:1
A human male produces sperms with the genotypes AB, Ab, aB and ab pertaining to two diallelic characters in equal proportions. What is the corresponding genotype of this person ?
(1) AaBb
(2) AaBB
(3) AABb
(4) AABB
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.
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.
A pure tall red plant is crossed with a pure dwarf white plant. The progenies thus produced in F1 generations are selfed. The different types of gametes that will be produed in F2 generaion will be
(1) 2
(2) 4
(3) 8
(4) 16
The ratio in a dihybrid test cross between two individuals is given by
(1) 2:1
(2) 1:2:1
(3) 3:1
(4) 1:1:1:1
In a plant, red fruit (R) dominant over yellow fruit (r) and tallness (T) is dominant over shortness (t). If a plant with RRTT genotype is crossed with a plant that is rrtt. Then
(1) 25% will be tall with red fruit
(2) 50% will be tall with red fruit
(3) 75% will be tall with red fruit
(4) All of the offspring will be tall with red fruits
Which of the following genotype express gametes?
(1) TtRrAa
(2) TtRA
(3) ATRr
(4) NMLr
In the results, F2 generation of Mendelian dihybrid cross in pea plant. The ratio of yellow and wrinkled seeded pea plant to the yellow and round seeded pea plant is
(1) 1 : 2
(2) 1 : 4
(3) 1 : 3
(4) 3 : 5
The minimum progeny population size allowing for random union of all kinds of gametes from AaBbCc parents is:
(1) 9
(2) 16
(3) 27
(4) 64