In which of the following crosses, will the F1 generation seed’s tall and dwarf traits appear in a 1:1 ratio?
(a) Tt x Tt
(b) TT x Tt
(c) TT x tt
(d) Tt x tt
WBBSE
Class X
Life Science
03 (a) Heredity
01 Mark
2025
(d) Tt x tt
Explanation:
When a heterozygous tall plant (Tt) is crossed with a homozygous dwarf plant (tt), the F1 progeny splits as:
| T | t | |
| t | Tt | tt |
| t | Tt | tt |
Tall seed = 2
Short seed = 2
Ratio = Tall : Short = 2 : 2 = 1 : 1
Related Questions
More WBBSE Moderate level questions
1/12
Q.
What will be the phenotypic ratio of progeny obtained from the hybridization between YyRR and...
A.
(c) 2:2
Q.
If a population undergoes three generations, and if each generation consists of only males, what...
A.
0% Explanation: If all generations consist only of males, there is no...
Q.
It is homozygous dominant in one locus and heterozygous dominant in the other locus –...
A.
False Explanation: A genotype that is homozygous dominant in one locus and...
Q.
The genotype of a guinea pig having black coloured and rough hair is _____
A.
BBRR / BbRr / BBRr / BbRR Explanation: In guinea pig, black...
Q.
What is the numerical ratio of the four genotypes BBRR, BBrr, bbRR and bbrr produced...
A.
(a) 1 : 1 : 1 : 1 Explanation: BR Br bR...
Q.
In spite of being pure in respect of one trait, what else could an organism...
A.
Heterozygous Explanation: An organism may be homozygous (pure) for one trait and...
Q.
Which would be the genotypic and phenotypic ratio in the F2 generation of a hybrid...
A.
(c) 1 : 2 : 1 Explanation In incomplete dominance, neither allele...
Q.
Which two of the following genotypes represent the genotype of a pea plant with yellow...
A.
YYrr or yyRr Explanation Seed colour and seed shape in pea plants...
Q.
As the gene responsible for haemophilia is recessive, so the symptoms of this disease is...
A.
homozygous recessive Explanation Haemophilia is a genetic disorder caused by a recessive...
Q.
Determine the nature of the pea plant germinated from the seed produced as a result...
A.
(b) 50% Tall, 50% Dwarf Explanation A hybrid tall plant (Tt) crossed...
Q.
Identify the genotype of guineapig having white coat colour and rough hair — (a) bbRR,...
A.
(c) bbRR, bbRr Explanation White coat colour is governed by recessive gene...
Q.
Black-smooth hair is produced in Fâ‚‚ generation resulting from a cross between pure black-rough haired...
A.
Genetic counselling detects carrier status in parents for autosomal recessive diseases like...