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

In a dihybrid cross, the F1 generation shows a phenotypic ratio of 1:1:1:2. What is the genotype ratio of the F2 generation?

  1. 9:3:3:1

  2. 1:2:1:2

  3. 3:1:1:3

  4. 1:1:1:1
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The F2 generation in a dihybrid cross will have a phenotypic ratio of 9:3:3:1, and a genotype ratio of 1:1:1:1.

Multiple choice

In a dihybrid cross, the F1 generation shows a phenotypic ratio of 1:1:2:4. What is the genotype ratio of the F2 generation?

  1. 9:3:3:1

  2. 1:2:1:2

  3. 3:1:1:3

  4. 1:1:1:1
Reveal answer Fill a bubble to check yourself
Correct answer
Explanation

The F2 generation in a dihybrid cross will have a phenotypic ratio of 9:3:3:1, and a genotype ratio of 1:1:2:4.

Multiple choice

In a dihybrid cross, the F1 generation shows a phenotypic ratio of 1:2:3:4. What is the genotype ratio of the F2 generation?

  1. 9:3:3:1

  2. 1:2:1:2

  3. 3:1:1:3

  4. 1:1:1:1
Reveal answer Fill a bubble to check yourself
Correct answer
Explanation

The F2 generation in a dihybrid cross will have a phenotypic ratio of 9:3:3:1, and a genotype ratio of 1:2:3:4.

Multiple choice

In a dihybrid cross, the F1 generation shows a phenotypic ratio of 1:2:3:6. What is the genotype ratio of the F2 generation?

  1. 9:3:3:1

  2. 1:2:1:2

  3. 3:1:1:3

  4. 1:1:1:1
Reveal answer Fill a bubble to check yourself
Correct answer
Explanation

The F2 generation in a dihybrid cross will have a phenotypic ratio of 9:3:3:1, and a genotype ratio of 1:2:3:6.

Multiple choice

What is the term used to describe an individual who has two identical alleles for a particular gene?

  1. Homozygous

  2. Heterozygous

  3. Dominant

  4. Recessive
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Homozygous individuals have two identical alleles for a particular gene, meaning they will express the same trait for that gene.

Multiple choice

What is the term used to describe an individual who has two different alleles for a particular gene?

  1. Homozygous

  2. Heterozygous

  3. Dominant

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

Heterozygous individuals have two different alleles for a particular gene, meaning they may express different traits for that gene.

Multiple choice

In a heterozygous individual, which allele is expressed?

  1. Dominant allele

  2. Recessive allele

  3. Both alleles

  4. Neither allele
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

In a heterozygous individual, the dominant allele is expressed, while the recessive allele is masked.

Multiple choice

In a homozygous individual, which allele is expressed?

  1. Dominant allele

  2. Recessive allele

  3. Both alleles

  4. Neither allele
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

In a homozygous individual, both alleles are identical, so both alleles are expressed.

Multiple choice

What is the probability of a homozygous dominant offspring from a cross between two heterozygous parents?

  1. 25%

  2. 50%

  3. 75%

  4. 100%
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

In a cross between two heterozygous parents, the probability of a homozygous dominant offspring is 25%.

Multiple choice

What is the probability of a homozygous recessive offspring from a cross between two heterozygous parents?

  1. 25%

  2. 50%

  3. 75%

  4. 100%
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

In a cross between two heterozygous parents, the probability of a homozygous recessive offspring is 25%.

Multiple choice

What is the probability of a heterozygous offspring from a cross between two heterozygous parents?

  1. 25%

  2. 50%

  3. 75%

  4. 100%
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

In a cross between two heterozygous parents, the probability of a heterozygous offspring is 50%.

Multiple choice

What is the term used to describe the alleles that are responsible for the same trait?

  1. Homozygous alleles

  2. Heterozygous alleles

  3. Dominant alleles

  4. Recessive alleles
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Homozygous alleles are alleles that are responsible for the same trait.

Multiple choice

What is the term used to describe the alleles that are responsible for different traits?

  1. Homozygous alleles

  2. Heterozygous alleles

  3. Dominant alleles

  4. Recessive alleles
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Heterozygous alleles are alleles that are responsible for different traits.

Multiple choice

What is the term used to describe the allele that is expressed in a heterozygous individual?

  1. Dominant allele

  2. Recessive allele

  3. Both alleles

  4. Neither allele
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

In a heterozygous individual, the dominant allele is expressed.

Multiple choice

What is the term used to describe the allele that is masked in a heterozygous individual?

  1. Dominant allele

  2. Recessive allele

  3. Both alleles

  4. Neither allele
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

In a heterozygous individual, the recessive allele is masked.