Biology

Genetics and Plant Breeding

1,177 Questions

Genetics and Plant Breeding explores the principles of heredity, chromosomal inheritance, and hybridization techniques. It includes key concepts like Mendelian genetics, gene linkage, and polygenic inheritance. This topic is essential for students tackling advanced biology or botany sections in competitive examinations.

Mendelian InheritanceChromosome TheoryGene LinkagePolygenic InheritancePlant HybridizationPopulation Genetics Equilibrium

Genetics and Plant Breeding Questions

Multiple choice

If a donor A sacrifices C offspring to help recipient B, its cousins to gain D offspring then the percentage relatedness of the donor to recipient is ______________.

  1. 50%

  2. 25%

  3. 30%

  4. 15%

  5. 100%
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

According to Hamilton's rule : The relatedness of an offspring to its parents is 0.5. So, with its cousins the relatedness will be (0.5×0.5) = 0.25. Instead of giving birth to its own offspring with relatedness of 0.5 helping other siblings to reproduce will increase the relatedness to 0.5× that number of offsprings.

Multiple choice

The phrase "like begets like" is best analysed in the context of which of the following?

  1. Forward genetics

  2. Classical genetics

  3. Reverse genetics

  4. Cytogenetics

  5. Both forward and classical genetics
Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

They deals with phenomenon of like begets like, e.g.,  human babies are like human beings in over all characteristics. As forward genetics is study on the basis of phenotype, study of DNA sequences comprising the gene for this phenotype and classical genetics is also known as transmission genetics, e.g.,: Mendelian genetics, Non-mendelian genetics.

Multiple choice

Which principle of Mendel is known as law of purity of gametes?

  1. Principle of Paired factor

  2. Principle of Dominance

  3. Principle of Segregation

  4. Principle of Independent assortment

  5. None of the above
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

It states that the two factors of a character segregate at the time of gamete formation and then reunite at the time of fertilisation. it is also known as law of purity of gamete.

Multiple choice

Which of the following is an example of incomplete dominance?

  1. Mirabilis jalapa

  2. Antirrhinum majus

  3. Pod colour in Andalusian fowl

  4. All of these

  5. None of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

In all of the above, the gene of allelomorphic pair are neither regarded as dominant nor recessive, but both of them express themselves partially in hybrid. Genotypic and Phenotypic ratio is the same.

Multiple choice

As per detailed investigation by S.Blixt on pea plant, on which of the chromosomes were the seven selected characters of Mendel were located?

  1. Chromosome number - 1, 3, 5 and 7

  2. Chromosome number - 1, 4, 5 and 7

  3. Chromosome number - 3, 4, 5 and 7

  4. Chromosome number - 1, 4, 5 and 11

  5. Chromosome number - 1, 3, 5 and 11
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

As per detailed investigation by S.Blixt on pea plant ,  7 selected characters were located on following chromosome -   stem height on chromosome number 4, flower colour on chromosome number 1, flower position on  chromosome number 4, pod shape on chromosome number 4, pod colour on chromosome number 5, seed shape on chromosome number 7 and seed colour on chromosome number 1.