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प्रश्न
A cross between a tall plant (TT) and short pea plant (tt) resulted in progeny that were all tall plants because
विकल्प
tallness is the dominant trait
shortness is the dominant trait
tallness is the recessive trait
height of pea plant is not governed by gene ‘T’ or ‘t’
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उत्तर
tallness is the dominant trait
Explanation -
In a cross between two organisms differing in one pair of contrasting traits, F1 hybrid shows only one of the parental traits, and this trait is called the dominant trait. Similarly, in the question, since the only tall trait is expressed in the progeny resulting from a cross between a tall plant and a short pea plant, tallness is the dominant trait.
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संबंधित प्रश्न
In a monohybrid cross between tall pea plants (TT) and short pea plants (tt), a scientist obtained only tall pea plants (Tt) in the F1 generation. However, on selfing the F1 generation pea plants, he obtained both tall and short plants in F2 generation. On the basis of above observations with other angiosperms also, can the scientist arrive at a law? If yes, explain the law. If not, give justification for your answer.
A Mendelian experiment consisted of breeding tall pea plants bearing violet flowers with short pea plants bearing white flowers. The progeny all bore violet flowers, but almost half of them were short. This suggests that the genetic make-up of the tall parent can be depicted as:
With the help of two suitable examples, explain why certain experiences and traits earned by people during their lifetime are not passed on to their next generations. When can such traits be passed on?
The gene for red hair is recessive to the gene for black hair. What will be the hair colour of a person if he inherits a gene for red hair from his mother and a gene for black hair from his father?
In the F2 generation of a cross, progeny having different traits are produced in the ratio 3 : 1. State whether it is a monohybrid cross or a dihybrid cross? Give one example of such a cross.
Gregor Mendel's first law of genetics states "Of a pair of contrasted characters, only one can be represented in a gamete by its internal 'factor' State where these factors are found in gametes.
Give the contrasting traits of the following characters in pea plant and mention which is dominant and which is recessive :
Round seed
For his experiments on heredity, Mendel used :
papaya plants
potato plants
pea plants
pear plants
In order to ensure that he had pure-breeding plants for his experiments, Mendel :
(a) cross-fertilised each variety with each other
(b) let each variety self fertilise for several generations
(c) removed the female parts of the plants
(d) removed the male parts of the plants.
A pregnant woman has an equal chance of her baby being blood group A or blood group AB. Which one of the following shows the possible genotypes of the woman and the father of her child?
(a) IA IA and IB IO
(b) IA IB and IB IO
(c) IA IO and IB IO
(d) IA IB and IA IO
If the ratio of each phenotype of the seeds of pea plants in the F2 generation is 9 : 3 : 3 : 1, it is known as :
(a) tetrahybrid ratio
(b) monohybrid ratio
(c) dihybrid ratio
(d) trihybrid ratio
What are the possible blood groups likely to be inherited by children born to a group A mother and a group B father? Explain your reasoning.
One of the following traits cannot be inherited. This one is:
Only one of the following characteristic of the parents can be inherited by their children. This one is:
If we pure-bred tall (dominant) pea plant with pure-bred dwarf (recessive) pea plant we will get pea plants of F1 generation. If we now self-cross the pea plant of F1 generation, then we obtain pea plants of F2 generation.
(a) What do the plants of F2 generation look like?
(b) State the ratio of tall plants to dwarf plants in F2 generation.
(c) State the type of plants not found in F1 generation but appeared in F2 generation, mentioning the reason for the same.
What will be the number of chromosomes present in each gamete produced by the plants if the palisade cells of a species of the plant contain 28 chromosomes in all?
Two pink coloured flowers on crossing resulted in 1 red, 2 pink and 1 white flower progeny. The nature of the cross will be
In human males all the chromosomes are paired perfectly except one. This/these unpaired chromosome is/are
- large chromosome
- small chromosome
- Y-chromosome
- X-chromosome
In the following figure showing a germinating gram seed, name the parts labelled as A, B and C:
Why is Part 'B' considered to be important during germination?
Name the following:
The basic units of heredity.
