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प्रश्न
Why did Mendel select pea plants for his experiment?
उत्तर १
Mendel selected pea plants for his experiment because of the following reasons :
- A pea plant has many contrasting characters.
- Self-fertilization takes place in pea plants and so it is possible to get a pure line of traits.
- Flowers are bisexual and hermaphrodite. Therefore, cross-pollination is achieved easily.
उत्तर २
- The pea plant is self-pollinating and so it is very easy to raise pure breeding individuals.
- It has a short life span, as it is annual.
- It is easy to cross-pollinate.
- It has deeply defined contrasting characters.
- The flowers are bisexual.
संबंधित प्रश्न
The F2 progeny of a monohybrid cross showed phenotypic and genotypic ratio as 1:2:1 unlike that the Mendel’s monohybrid F2 ratio. With the help of a suitable example, work out a cross and explain how it is possible.
In a homozygous pea plant, axial flowers (A) are dominant over terminal flowers (a).
(i) What is the phenotype and genotype of the F1 generation if a plant bearing pure axial flowers is crossed with a plant bearing pure terminal flowers?
(ii) Draw a Punnett square board to show the gametes and offsprings when both the parent plants are heterozygous for axial flowers.
(iii) What is the phenotypic ratio and genotypic ratio of the above cross shown in (ii)?
(iv) State Mendel’s Law of Dominance.
(v) Name two genetic disorders commonly seen in human males.
The cross between two parents having one pair of contrasting characters
Mention the Phenotype and Genotype ratios of the offspring in F2 generation.
Give any four reasons for Mendel's success.
Select the most appropriate option
Which one of the following has the smallest number of chromosomes?
(a) Onion
(b) Mouse
(c) Monkey
(d) Ascaris
In Mendel’s experiments, tall pea plants (T) are dominant over dwarf pea plants (t).
What is the phenotype and genotype of the F1 generation if a homozygous tall plant is crossed with a homozygous dwarf plant?
In Mendel’s experiments, tall pea plants (T) are dominant over dwarf pea plants (t).
What is the phenotypic ratio and genotypic ratio of the above cross in (ii)?
Distinguish between monohybrid and dihybrid cross.
Predict the genotype and phenotype of the following cross in pea.
TTrr x ttRR
(Capital letters show dominance)
Choose the correct answer:
The contrasting characters used by Mendel are called _____
In heterozygous condition, both the alleles are expressed in ______
When two genetic loci produce identical phenotypes in cis and trans position, they are considered to be ______.
Mendel’s law of independent assortment does not hold true for the genes that are located closely on ______.
A heterozygous violet-flowered pea plant is crossed to another homozygous violet- flowered pea plant. What percent of the progeny plants will have the recessive trait, i.e., white flowers?
Read the following and answer from given below:
Prashant wanted to find the genotype of a pea plant bearing purple coloured flowers in his kitchen garden. For this, he crossed purple-flowered plants with white-flowered plants. As a result, all plants which were produced had purple flowers only. Upon selfing these plants, 75 purple flower plants and 25 white flowers plants were produced. Now, he can determine the genotype of a purple-flowered plant by crossing it with a white-flowered plant.
In white-flowered plants, the allele is expressed in ______
New species may be formed if
- DNA undergoes significant changes in germ cells
- chromosome number changes in the gamete
- there is no change in the genetic material
- mating does not take place
Two pea plants one with round green seeds (RRyy) and another with wrinkled yellow (rrYY) seeds produce F1 progeny that have round, yellow (RrYy) seeds. When F1 plants are selfed, the F2 progeny will have new combination of characters. Choose the new combination from the following
- Round, yellow
- Round, green
- Wrinkled, yellow
- Wrinkled, green
If a cross between two individuals produces offspring with 50% dominant character (A) and 50% recessive character (a) then the Genotypes of parents are:
Do you think Mendel’s laws of inheritance would have been different if the characters that he chose were located on the same chromosome.
