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

In which mode of inheritance do you expect more maternal influence among the offspring?

  1. Autosomal

  2. Cytoplasmic

  3. Y-linked

  4. X-linked
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Cytoplasmic inheritance shows stronger maternal influence because organelles like mitochondria and chloroplasts (which have their own DNA) are inherited primarily through the egg's cytoplasm. The sperm contributes mainly nuclear DNA with minimal cytoplasm. X-linked inheritance comes from both parents (mother's X and father's X or Y).

Multiple choice

Cross breeding is the crossing of two different pure breeds or populations, as a result of mixing the genetic contributions of its parents the offspring exhibit the characters of both the parents. What is this condition referred to as?

  1. Co-dominace

  2. Dominant epistasis

  3. Heterosis

  4. Duplicate Dominant Interaction
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Heterosis is the improved or increased function of any biological quality in a hybrid offspring. An offspring exhibits heterosis if its traits are enhanced as a result of mixing the genetic contributions of its parents.

Multiple choice

In maize, hybrid vigour is exploited by

  1. bombarding the protoplast with DNA

  2. crossing of two inbreed parental lines

  3. harvesting seeds from the most productive plants

  4. inducing mutations
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

In maize, hybrid vigour is exploited by crossing of two inbreed parental lines. 

Multiple choice

Which of the following shows codominance pattern of inheritance?

  1. Flower colour in garden pea

  2. Flower colour in snapdragon

  3. ABO blood group

  4. Both 2 and 3
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Snapdragon flower color: FRallele is for red flower colour and FWallele for white flower and in when both FRFW condition it will be pink due to codominance and in ABO blood group A and B alleles are codominant to each other. 

Multiple choice

Which of the following statements are FALSE?

  1. In Drosophila, the genotype of normal wings is Vg+.
  2. Multiple alleles of a gene always occupy the same locus on a chromosome.
  3. In pleiotropic inheritance, different traits are controlled by different genes.
  4. Skin colour is controlled by 2 pairs of genes.

  1. 1 and 2

  2. 1 and 4

  3. 2 and 3

  4. 2 and 4

  5. 3 and 4
Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

Both are false statements. In pleiotropic inheritance, different traits are controlled by a single gene. Skin colour is controlled by 3 pairs of genes. This is the correct answer.

Multiple choice

Identify the FALSE statements.

  1. Law of independent assortment is applicable for the traits which are located on different chromosomes.
  2. Interaction between two alleles which are present on the same gene locus of two homologous chromosomes is called intergenic interaction.
  3. Second law of inheritance proposed by Mendel deals with segregation.

  1. Only 1

  2. Only 2

  3. Only 3

  4. 1 and 2

  5. 1 and 3
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Correct answer. Interaction between two alleles which are present on the same gene locus of two homologous chromosomes is called intragenic interaction. Interaction between the alleles of different genes on the same or different chromosome is called intergenic interaction.  

Multiple choice

The golden 2 like (GLK) genes were discovered in maize in 2001. Which of the following functions do they perform?

  1. CA1P-phosphatase regulation

  2. Phosphoenol carboxylase regulation

  3. Chloroplast development

  4. NADP-malic enzyme regulation
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

GLK gene pairs regulate chloroplast development in diverse plant species. As GLK genes are not found in any algal or non-plant genomes, GLK transcription factors evolved to regulate chloroplast development as plants moved on to land.