HARD
12th CBSE
IMPORTANT
Earn 100
Even if a character shows multiple allelism, an individual will only have two alleles for that character. Why?
Important Questions on Principle of Inheritance and Variation
HARD
12th CBSE
IMPORTANT
How does a mutagen induce mutation? Explain with example.
MEDIUM
12th CBSE
IMPORTANT
In a Mendelian monohybrid cross, the F2 generation shows identical genotypic and phenotypic ratios. What does it tell us about the nature of alleles involved? Justify your answer.
HARD
12th CBSE
IMPORTANT
Can a child have blood group O if his parents have blood group 'A' and 'B'? Explain.
HARD
12th CBSE
IMPORTANT
What is Down's syndrome? Give its symptoms and cause. Why is it that the chances of having a child with Down's syndrome increases if the age of the mother exceeds forty years?
HARD
12th CBSE
IMPORTANT
How was it concluded that genes are located on chromosomes?
HARD
12th CBSE
IMPORTANT
A plant with red flowers was crossed with another plant with yellow flowers. If F1 showed all flowers orange in colour, explain the inheritance.
HARD
12th CBSE
IMPORTANT
What are the characteristic features of a true-breeding line?
HARD
12th CBSE
IMPORTANT
In peas, tallness is dominant over dwarfness, and red colour of flowers is dominant over the white colour. When a tall plant bearing red flowers was pollinated with a dwarf plant bearing white flowers, the different phenotypic groups were obtained in the progeny in numbers mentioned against them:
Tall, Red = 138
Tall, White = 132
Dwarf, Red = 136
Dwarf, White = 128
Mention the genotypes of the two parents and of the four offspring types.
