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MCQs on Genetics

MCQs on Genetics : In this article we are going to discuss about the MCQs of Genetics and many more.

Genetics is the study of genes and heredity, or how specific attributes or traits are passed down through generations as a result of changes in DNA sequence. A gene is a piece of DNA that includes instructions for constructing one or more molecules that aid the body’s function. The double helix is fashioned like a corkscrew-twisted ladder. 

The backbones are the two ladder rails, and the rungs are pairs of four building bricks known as bases. The sequences of these bases serve as blueprints for constructing molecules, the majority of which are proteins. Humans are thought to have around 20,000 genes, according to researchers.

The genome contains all of an organism’s genetic material, including its genes and other elements that regulate gene function.

Question 1.

The tendency of an offspring to resemble its parent is known as

  1. Variation
  2. Resemblance
  3. Heredity
  4. Inheritance

Answer: The Correct Answer is Heredity. Heredity is the natural predisposition of kids to resemble their parents.

Question 2.

Who is known as the “Father of Genetics”?

  1. Mendel
  2. Morgan
  3. Bateson
  4. Watson

Answer: The correct answer is Mendel. Mendel, Gregor The study of Gregor Mendel on peas led to our knowledge of inheritance’s fundamental principles. Genetics’ Forefather. Gregor Mendel’s work, like that of many great artists, was not appreciated until after his death.

Question 3.

The alternate form of a gene is

  1. Recessive character
  2. Alternate type
  3. Allele
  4. Dominant character

Answer: The Correct answer is Allele. Alleles are different versions of the same gene that might be dominant or recessive. Alleles for a characteristic are found in the same place on homologous chromosomes and so rule the same trait.

Question 4.

The genotypic ratio of a monohybrid cross is

  1. 3:1
  2. 1:2:1
  3. 9:3:3:1
  4. 2:1:1

Solution: The Correct answer is 1:2:1. A monohybrid cross produces a 3:1 (dominant to recessive) phenotypic ratio and a 1:2:1 genotypic ratio (homozygous dominant to heterozygous to homozygous recessive).

Question 5.

The crossing of F1 to either of the parents is known as

  1. Test cross
  2. F1 cross
  3. Back cross
  4. All of the above

Solution: The Correct answer is Black Cross. Backcrossing is the process of crossing a hybrid with one of its parents or a genetically related individual in order to produce offspring with a genetic identity comparable to that of the parent.

Question 6.

Which of the following statements is true regarding the “law of segregation”?

  1. Segregation of factors is due to the segregation of chromosomes during meiosis
  2. Law of segregation is the law of purity of genes
  3. Alleles separate from each other during gametogenesis
  4. All of the above

Solution: The correct answer is all of the above. After his pea studies, Gregor Mendel established the law of segregation. During episodes of separation, such as gametogenesis, the paired alleles split and migrate independently.

Question 7.

Homozygosity and heterozygosity of an individual can be determined by

  1. Test cross
  2. Back cross
  3. Self-fertilization
  4. All of the above

Solution: The Correct option is Test Cross. Test crosses are created by crossing F1 individuals with homozygous recessive progeny. It’s used to see if F1 offspring are homozygous or heterozygous.

Question 8.

An exception to Mendel’s law is

  1. Linkage
  2. Independent assortment
  3. Purity of gametes
  4. Dominance

Solution: The Correct answer is Linkage. Genetic linkage refers to the likelihood for alleles on the same chromosome to be inherited together during meiosis. Genes with closer loci are less likely to be divided onto different chromatids during the chromosomal crossover, and thus are said to be genetically connected.

Complete dominance is a type of intermediate inheritance in which one allele for a trait is not fully expressed over its paired allele. As a result, a third phenotype emerges, in which the expressed physical attribute is a mix of dominant and recessive traits.

Question 9.

Pea plants were used in Mendel’s experiments because

  1. They were cheap
  2. They were available easily
  3. They had contrasting characters
  4. All of the above

Solution: The Correct answer is they had contrasting characters. Pea plants were chosen by Mendel because they had easily observable qualities and each character had two opposing observable traits. Mendel observed and employed (manipulated) seven pairs of such opposing features in his tests. As a result, the correct answer is ‘They had seven pairs of contrasting characteristics.’

Question 10.

The smallest unit of genetic material which produces a phenotypic effect on mutation is

  1. Gene
  2. Muton
  3. Nucleic acid
  4. Recon

Solution: The Correct answer is Muton. A gene has many cistrons, which are functional units that pass the cis-trans test. Recon is the smallest unit capable of undergoing recombination. One to multiple mutons make up a recon, which is the smallest unit of mutation. 

The inducer is a molecule that attaches to the repressor and causes it to change conformation, preventing it from binding to the operator. The protein products of the regulator gene, which are usually transcription factors, regulate the expression of structural genes. These transcription factors attach to the operator region, which is immediately upstream of the RNA polymerase binding site, and so block RNA polymerase binding and transcription.

Question 11.

Mendel’s findings were rediscovered by

  1. Correns
  2. Tschermark
  3. De Vries
  4. All

Answer: The Correct answer is All. 

Question 12.

Alleles are

  1. Linked genes
  2. Alternate forms of genes
  3. Homologous chromosomes
  4. Chromosomes that have crossed over

Answer: The Correct answer is Alternate forms of genes. A variable form of a gene is known as an allele. Some genes exist in several distinct versions, all of which are found at the same genetic locus on a chromosome. Humans are referred to as diploid organisms because they have two alleles at each genetic locus, one from each parent.

Question 13. 

 Cystic fibrosis is

  1. Autosomal dominant disorder
  2. Sex-linked recessive disorder
  3. Sex-linked dominant disorder
  4. Autosomal recessive disorder

Solution: The Correct answer is Autosomal recessive Disorder. Cystic fibrosis (CF) is a genetic disease that affects the lungs, digestive system, and other organs in the body. The cells that create mucus, perspiration, and digestive fluids are affected by cystic fibrosis. Normally, these produced fluids are thin and slick.