Biology

Genetics and Plant Breeding

1,240 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

Siamese twins mean

  1. that twins are formed from the single zygote and are not separated

  2. that twins are produced from two zygotes

  3. that twins are produced from three zygotes

  4. that twins are borne in Siamese countries
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

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Multiple choice

A married couple adopted a male child. A few years later, twin boys were born to them. The blood group of the couple is AB positive and O negative. The blood group of the three sons is A positive, B positive, and O positive. The blood group of the adopted son is

  1. O positive

  2. A positive

  3. B positive

  4. Cannot be determined on the basis of the given data.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

AB positive partner forms two type of gametes; A positive and B positive.  O negative partner forms only single type of gamete O negative.  Two type of zygote formation occur A+O- (A positive) and B+O- (B positive). The blood group of the adopted son will be O positive. 

Multiple choice

Which of the following terms were coined by Wilhelm Johansen?

  1. Gene, Allele, Genetics

  2. Gene, Genotype, Phenotype

  3. Factor, Genotyepe, Phenotype

  4. Allele, Genotype, Genetics

  5. Â Phenotype, factor, Allele
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Danish botanist Wilhelm Johannsen coined the word gene in 1909 to describe these fundamental physical and functional units of heredity. Wilhelm Johannsen coined the terms genotype and phenotype in 1911.

Multiple choice

Choose the incorrect pair.

  1. Diabetesis-Hexokinase

  2. Albinism-Tyrosinase

  3. Tyrosinosis-Tyrosine hydroxylase

  4. PKU-Phenylalanine hydroxylase
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Deficiency or absence of both fumarylacetoacetate hydroxylase and melanylacetoacetate isomerase enzymes causes Tyrosinosis.

Multiple choice

A genetic experiment was performed to map the gene (s) for eye colour in a newly-discovered moth species. Sex determination in this moth species: XY — male and XX — female. When blue-eyed males were mated to green-eyed females, all of both male and female progeny had green eyes. When these progeny were mated among themselves, about half of the males of the resulting second generation had blue eyes; however, all females were green-eyed. Which one of the following is consistent with the above data?

  1. Multiple genes control eye colour in this moth species.

  2. Gene(s) for eye colour is located on the X chromosome.

  3. Gene(s) for eye colour is located on the Y chromosome.

  4. Gene(s) for eye colour may not be sex-linked.
Reveal answer Fill a bubble to check yourself
A Correct answer
Multiple choice biology food production uses of animals agro-complimentary occupations improvement of crop production

Hybridisation refers to crossing between genetically ______ plants.

  1. Similar

  2. Dissimilar

  3. Both A or B

  4. None of the above
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

One way of incorporating desirable characters into crop varieties is by hybridisation. Hybridisation refers to crossing between genetically dissimilar plants.

Thus, the correct answer is option B.