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 zoology environmental factors soil-nature climate factors abiotic components organisms and environment

Ecotype is a type of species in which environmentally induced variations are

  1. Temporary

  2. Genetically fixed

  3. Genetically not related

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

An ecotype is a distinct population within a species that has adapted to specific local environmental conditions. These adaptations are genetically fixed, meaning they are inherited and persist even if the organism is moved to a different environment.

Multiple choice population and how it changes human population ecology and environment zoology

The transient population between two adjacent ecotypes is called as

  1. Deme

  2. Polytypic

  3. Cline

  4. Hybrid
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The diverse climate and the seasonal variations lead to the formation of several zones having flora and fauna with the phenotypic difference. An ecocline or simply cline describes an ecotone in which a series of biocommunities display a continuous gradient. The term was coined by the Huxley in 1938. Clines are the source of genetic and phenotypic variations. It consists of different forms of species, that exhibit gradual phenotypic and / or genetic differences over a geographical area, typically as a result of  diverse environmental condition. 

Multiple choice population and how it changes human population ecology and environment zoology

Two populations of a species of pine tree are located on opposite sides of a mountain range. The two populations are genetically similar to each other.
An invasive beetle infestation kills 80% of the trees on the west side of the range. The beetle population does not spread to the eastern side of the range, and the east tree population does not experience any beetle related loss. After the infestation, the western tree population increases in size again.
What is the expected outcome of genetic testing comparing the two populations?

  1. The genetic diversity of the west population is higher than the east population.

  2. The phenotypic variation of the west population is higher than the east population.

  3. The two populations are less genetically similar than they were prior to the beetle infestation.

  4. The two populations remain genetically similar.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Due to beetle infestation, 80% of the trees on the west side of the range were killed. This will result in the alteration of allele frequencies. Certain alleles are lost during infestation. In the small population of the west side, genetic diversity is less compared to that of a large population in the east. Due to less genetic diversity, phenotypic variations will also be lower on the west side. Hence, the two side of populations will be less genetically similar than the earlier. 

Thus, the correct answer is 'The two populations are less genetically similar than they were prior to the beetle infestation.'

Multiple choice population and how it changes human population ecology and environment zoology

For natural selection to occur, which of the following must be true for a population of organisms?

  1. Phenotypic variations must be based on genetic variations rather than on varying environmental conditions.

  2. The population must be occupying the same niche as another local population.

  3. Organisms in the population must be capable of sexual reproduction.

  4. Food resources must be limited.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Evolution takes place due to various reasons like natural selection, mutation, genetic drift. Phenotypic variations must be based on genetic variations rather than on varying environmental conditions. Sexual reproduction results in the genetic variation but does not affect the natural selection. Also, limited food resources may drive natural selection but is not the reason for natural selection to occur.

Thus, the correct answer is 'Phenotypic variations must be based on genetic variations rather than on varying environmental conditions.'

Multiple choice zoology plant reproduction different modes of reproduction sexual and asexual reproduction lifespan, reproduction and variation

Offspring formed by sexual reproduction exhibit more variation than those formed by asexual reproduction because

  1. Sexual reproduction is a lengthy process

  2. Gametes of parents have qualitatively different genetic composition

  3. Genetic material comes from parents of two different species

  4. Greater amount of DNA is involved in sexual reproduction
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Asexual reproduction is a type of reproduction by which offspring arise from a single organism, and inherit the genes of that single parent only. During sexual reproduction, fertilization creates a single-celled zygote which includes genetic material from both gametes. Therefore, the complex mixture of genetic material causes a great variation in the offspring. 
So, the correct option is 'Gametes of parents have qualitatively different genetic composition'.



Multiple choice zoology plant reproduction different modes of reproduction sexual and asexual reproduction lifespan, reproduction and variation

________ is the disadvantage of asexual reproduction

  1. Repid reproduction

  2. Lack of genetic variation

  3. Both a and b

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

In asexual reproduction only one parent is involved so there is no fusion of two cells, the daughter cells produced by asexual reproduction are genetically identical to the parent cells variations enable organisms to adopt and survive in changing environment and it helps to prevent the complete extinction of specters. so lack of genetic variation is the disadvantage.
 Whereas rapid reproduction is the advantage of asexual reproduction.

So, the correct answer is ' Both a and b'.

Multiple choice zoology plant reproduction different modes of reproduction sexual and asexual reproduction lifespan, reproduction and variation

One advantage of sexual reproduction is that it allows for genetic sameness.

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

  • In sexual reproduction, two individuals are involved and there is the genetic exchange between the male and female. 
  • As there is an exchange of genetic material, the offspring, won't have exactly the same material as either of his parents. 
  • There will be a different genetic content of each offspring, every time. As a result, there is no genetic sameness instead, sexual reproduction leads to variation.

Multiple choice zoology plant reproduction different modes of reproduction sexual and asexual reproduction lifespan, reproduction and variation

......................... reproduction causes greater diversity.

  1. Sexual

  2. Asexual

  3. Both A and B

  4. None of the above
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
Sexual reproduction causes greater genetic diversity because the sperm and egg with a different set of genes fuse to form new individual and further mixes the genes to produce more genetic diversity. 
Asexual reproduction is the process where one organism divides into two without shuffling its genes, so the offspring has the same version of genes as the parent. Thus, the correct answer is option A.
Multiple choice biology life processes: reproduction, growth and development different types of reproduction reproductive health of humans need of family planning

Why asexual reproduction is sometimes disadvantageous?

  1. It allows animals that do not move around to produce offspring without finding mates

  2. It allows an animal to produce many offspring quickly

  3. It saves the time and energy of gamete production

  4. It produces genetically uniform populations
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Asexual reproduction is a type of reproduction by which offspring arise from a single organism, and inherit the genes of that parent only; it does not involve the fusion of gametes, and almost never changes the number of chromosomes. It produces genetically uniform populations.

So, the correct option is 'Option D'.

Multiple choice evs animal- the base of our life diversity in the living world environmental conservation and biodiversity biodiversity on earth and in india

Assertion : Alpha diversity is said to be higher if the dissimilarity between local pool species.

Reason : Alpha diversity is a measure of diversity between the communities in a local area.

  1. Both the Assertion and the Reason are true and the Reason is a correct explanation of the Assertion

  2. Both the Assertion and the Reason are true but the Reason is not a correct explanation of the Assertion.

  3. The Assertion is true but the Reason is false.

  4. Both the Assertion and Reason are true.

  5. The Assertion is false but Reason is true.
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

A local pool species includes all the available species in a given area. The species diversity in a local community is called alpha diversity. It is said to be higher if there is a dissimilarity between local pool species. This diversity is influenced by the interaction between the biotic and abiotic factors. It also depends on immigration. Thus the correct answer is option D.

Multiple choice evs animal- the base of our life diversity in the living world environmental conservation and biodiversity biodiversity on earth and in india

Which of the following will not affect the frequency of the gene in a large population?

  1. A) Environmental selective pressure

  2. B) selective immigration

  3. C) Random mating

  4. D) Non random mating
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
  • Selective pressures drive natural selection.
  •  Some members of the population will not survive and reproduce and, thus, will not pass on their genes into the next generation. This change in the genetic makeup of a population is called evolution. 
  • Hence, Environmental selective pressure will not affect the frequency of the gene in a large population. 
  • So, the correct answer is 'Environmental selective pressure'.
Multiple choice botany plant breeding method of plant breeding for crop improvement plant breeding for food production biotechnology

Which is not applicable to the biological species concept?

  1. Hybridization

  2. Natural population

  3. Reproductive isolation

  4. Gene Pool
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
The biological species concept defines a species as a members of populations that potentially interbreed in nature. The biological species concept explains species resemblance and how some differ from other species. Offspring has fusion of parent's genes. As the generation increases, the genes of different organisms are constantly shuffled around the species gene pool. The shared gene pool gives the species its identity. Genes are not transferred to other species and different species thus, take on a different phenotype. Interbreeding between species is prevented by isolating mechanisms. The biological species concept centers on this inability to successfully hybridize
 So, the correct answer is 'Hybridization'
Multiple choice botany plant breeding method of plant breeding for crop improvement plant breeding for food production biotechnology

Collection of genetic variability is required in plant breeding programme because

  1. It leads to inbreeding depression in hybrids

  2. It is the root of any breeding programme

  3. Diverse alleles in germplasm helps you to choose desirable charters

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

Genetic variability is the cornerstone of breeding with the advent of molecular biology, traditional interspecific, intergenetic and plant type barriers to gene transfer have been removed. By isolating the gene for a particular trait and inserting it into a new host by a range of techniques the gene becomes a part of the host.DNA.

So, the correct option is 'Both (2) and (3)'.

Multiple choice botany pollination, fertilization and development of endosperm and embryo types of pollination cross pollination pollination and its types

Allogamy is very useful because it results in ...............

  1. Formation of male off-springs

  2. Weaker progeny

  3. Superior progeny

  4. formation of seeds
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Allogamy is also called as cross pollination. In the case of allogamy, the pollen from a flower falls on the flower of a different plant. This causes the genetic recombinations to take place. This is not possible in any other type of pollinations. Thus it produces the superior progeny.