Biology

Genetics and Evolutionary Biology

1,123 Questions

Genetics and evolutionary biology explain how traits are passed from parents to offspring and how species change over time. Key concepts include genetic drift, inbreeding, and heredity. This topic is fundamental for the biology section of many competitive tests.

Heredity and traitsGenetic variations and driftInbreeding conceptsEvolutionary mechanisms

Genetics and Evolutionary Biology Questions

Multiple choice

Which type of mutation does not result in the absence of mutagens?

  1. Point mutation

  2. Frameshift mutation

  3. Induced mutation

  4. Spontaneous mutation

  5. Nonsense mutation
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

It occurs when an organism is exposed to a physical or chemical agent known as mutagen that interacts with DNA to cause a mutation. Induced mutations typically occur at a much higher frequency than spontaneous mutations. The first induced mutations were created by treating Drosophila with X-rays.

Multiple choice

Which of the following statements regarding mutation is not correct?

  1. It is a change in the hereditary material of life.

  2. It is the raw material of genetic variation.

  3. In the absence of mutation, evolution cannot occur.

  4. Some mutations result in an incomplete protein.

  5. External influences cannot create mutation.
Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

Mutation is affected by external influences. Mutations can be caused by exposure to specific chemicals or radiation. These agents cause the DNA to break down. This is not necessarily unnatural even in the most isolated and pristine environments DNA breaks down.

Multiple choice

Which of the following factors are involved in the formation of new species?

  1. Isolation and mutation

  2. Competition and variation

  3. Isolation and competition

  4. Competition and mutation
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

New species formation requires both isolation (geographic, reproductive, or temporal) to prevent gene flow and mutations to create genetic divergence. While competition and variation influence evolution, isolation and mutation are the primary drivers of speciation.

Multiple choice

The ultimate source of organic variation is

  1. natural selection

  2. sexual reproduction

  3. hormonal action

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

Mutation is the ultimate source of all genetic variation in organisms. Mutations are random changes in DNA that create new alleles. Natural selection acts on existing variation, sexual reproduction reshuffles it, and hormones don't create genetic variation. Without mutation, there would be no new genetic material for evolution to work on.

Multiple choice

Random amplified polymorphic DNA is a technique for

  1. cross linkage of antigens by antibodies

  2. revealing intra-specific variation and diversity between species

  3. selection of somaclones that are resistant to herbicides

  4. reduction or elimination of the expression of individual genes

  5. transferring geometric shapes on a mask to the surface of a silicon wafer
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Random amplified polymorphic DNA (RAPD) is a method that reveals intra-specific variation and diversity between species.

Multiple choice

Which of the following is associated with robust populations that can survive bouts of intense selection?

  1. Proteome

  2. Proteomics

  3. Functional genomics

  4. Genome

  5. Gene pool
Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

Gene pool is associated with robust populations that can survive bouts of intense selection. Meanwhile, low genetic diversity (see inbreeding and population bottlenecks) can cause reduced biological fitness and an increased chance of extinction, although as explained by genetic drift, new genetic variants, which may cause an increase in the fitness of organisms, are more likely to fix in the population if it is rather small.

Multiple choice

Consider the following statements:

  1. Selective breeding is the process of insertion of genes in plants and animals for desirable traits.
  2. DNA fingerprinting was started in USA.

Which of the given statements is/are incorrect?

  1. Only 1

  2. Only 2

  3. Both 1 and 2

  4. Neither 1 nor 2
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Statement (1) is correct. Selective breeding (also called artificial selection and unnatural selection) is the process of is the process of insertion of genes in plants and animals for desirable traits. Statement 2 is incorrect. DNA fingerprinting was started by Alec Jeffrey in UK.

Multiple choice

Consider the following statements: (1) The chemicals, which can cause the genetic variation are called mutagens. (2) Ionising radiations (X-rays, gamma rays, cosmic rays, etc.) can cause genetic variation.

Which of the given statements is/are correct?

  1. Only 1

  2. Only 2

  3. Both 1 and 2

  4. Neither 1 nor 2
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Statement (1) is correct. Mutagens are the chemicals, which can cause the genetic variation. For example, nitrous acid, alkylating agents,etc. Statement (2) is also correct. The ionising radiations (X-rays, gamma rays, cosmic rays, etc.) can cause the genetic variation.

Multiple choice

Consider the following statements:

  1. Heredity is not responsible for the development of new species.
  2. The human traits are influenced by DNA of both mother and father.

Which of the given statements is/are correct?

  1. Only 1

  2. Only 2

  3. Both 1 and 2

  4. Neither 1 nor 2
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Statement (1) is correct. Heredity is not responsible for the development of new species. Statement (2) is also correct. The human traits are influenced from the DNA of both mother and father.

Multiple choice

Which of the following is responsible for allopatric speciation?

  1. It occurs when genetically related populations inhabit a widely separated geographical area.

  2. It occurs when genetically unrelated populations inhabit a widely separated geographical area.

  3. It occurs when genetically related populations inhabit the same geographical area.

  4. It occurs when genetically mixed populations inhabit the geographical area.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

During the course of allopatric speciation, a part of the population become geographically isolated from the main population.

Multiple choice

Match the following and choose the correct option given below ||| |---|---| |A. Cline|i. It is an assemblage of closely related interbreeding individuals of a species.| |B. Biotype|ii. Transient population between species having the same genotypes and species having different genotypes.| |C. Ecotype|iii. Group of individuals of a species having the same genotype.| |D. Deme|iv. Genetically different populations of a species colonizing different specific habitat.|

  1. A – iv, B – iii, C – ii, D – i

  2. A – ii, B – iii, C – iv, D – i

  3. A – iii, B – ii, C – iv, D – i

  4. A – iii, B – iv, C – i, D – ii
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Cline – Transient population between species having same genotypes and species having different genotypes.  Biotype - Group of individuals of a species having same type of genotype.  Ecotype - Genetically different populations of a species colonizing different specific habitat. Deme - It is an assemblage of closely related interbreeding individuals of a species.