Biology

Genetics and Evolutionary Biology

1,156 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 botany classical genetics variation and its type natural selection introduction to genetics

In introgressive hybridization, one species is completely replaced by another in nature.

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
he movement of a gene (gene flow) from one species into the gene pool of another by the repeated backcrossing of an interspecific hybrid with one of its parent species is called Introgressive hybridization.
So the given statement is true.
Multiple choice biology variation variation and its type natural selection introduction to genetics

There is an inbuilt tendency to variation during reproduction, because of errors in DNA copying and as a result of sexual reproduction.

  1. True

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

Sexual reproduction results in more variation than the asexual reproduction. During sexual reproduction, there are chances of errors occurring during DNA copying. Crossing over also takes place during sexual reproduction. All these ultimately result in the variation. This variation helps survival in species and also supports diversity in the course of evolution.

Thus, the correct answer is option A.

Multiple choice biology variation variation and its type natural selection introduction to genetics

To be evolutionary successful, the mutation must occur in 

  1. Somatoplasm

  2. Germplasm

  3. Karyolymph/zygote

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

Total of specialized protoplasm other than germplasm in individual body or protoplasm of somatic cells is termed as somatoplasm. Germplasm is protoplasm of germ cells (egg and sperm cells) or any living tissues with the capability of generating new organisms. The germplasm is inherited from parents to offspring along with gametes; thus any mutation in germplasm is passed to progeny which is a requisite for successful mutation; option B is correct. Since somatoplasm is not passed to offspring, any mutation in it affects that individual only and is not passed to offspring which makes option A incorrect. The liquid phase of cell nucleus which harbours the nucleolus and chromatin and other structures is called as karyolymph. Similarly, the mutation in zygote affects single individual that develops from that zygote. Option C is incorrect. The granular endoplasmic reticulum that has studded ribosomes on its surface is called as ergastoplasm which is not inherited to offspring and thus is not suitable for successful mutation; option D is incorrect. Correct option B is correct. 

Multiple choice biology water absorption and ascent of sap in plants transport of water across plants habit of plants plant classifications

Join properly Column-I and Column-II.

Column-I Column-II
(a) Henking $(1)$ Study of chromosomes in plants
(b) Bridges $(2)$ Environmental effect of sex determination
(c) Baltzer $(3)$ X-body
(d) Allen $(4)$ Law of genetic balance
  1. a-$4$, b-$3$, c-$2$, d-$1$
  2. a-$3$, b-$2$, c-$4$, d-$1$
  3. a-$3$, b-$4$, c-$2$, d-$1$
  4. a-$1$, b-$2$, c-$3$, d-$4$
Reveal answer Fill a bubble to check yourself
A Correct answer
Multiple choice zoology applications of biotechnology cloning process of cloning gene cloning

Individuals of a clone have the

  1. Same behavior.

  2. Same height.

  3. Same genome.

  4. Same number of leaves.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
The individual produced by the asexual reproduction are considered as a clone of their own parents and have same genome because of the following reasons:
1) Fusion of gametes does not takes place in asexual reproduction so there is no chance of recombination and variation.
2) The parent cell divides to form daughter cell by mitosis due to which the offspring is genetically identical to the parent.
3) The offspring produced are clones of their parent and have same number of chromosomes.
So, the correct answer is option C.
Multiple choice zoology molecular basis of inheritance the search for genetic material dna structure and replication molecular genetics

A molecule that acts as a genetic material must fulfill the traits given, except

  1. It should provide the scope for slow changes that are required for evolution

  2. It should be able to generate its replica

  3. It should be able to express itself in the form of Mendelian characters

  4. It should be unstable structurally and chemically
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Genetic material must be stable to store information accurately over generations. If it were unstable, it could not reliably pass on traits.

Multiple choice biology the life cycle of animals how do animals reproduce? excretory, nervous and reproductive system structure and functions of living organisms -ii

Choose the correct answers from the alternatives given. 
Reproduction

  1. is a universal feature of all living organisms

  2. produces genetic variation that is important in survival of a species

  3. enables a species to persist over long periods of time

  4. all of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Reproduction is a biological process by which new individual organism is produced from their parents. Reproduction is a fundamental feature of all life. Reproduction helps the species to live a long period of life. Sexual reproduction also links with a variation in species which help in them for survival. 

Hence, the correct answer is 'all of the above'

Multiple choice biology concept of life theories of the origin of life origin of life the origin of cells and cell division

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

Speciation often requires reproductive isolation to prevent gene flow between populations, while mutations provide the genetic variation necessary for natural selection to act upon.

Multiple choice biology habits and habitats of some important animals behavioural science ethology animal behaviour

Which of the following explains that structural differences prevent mating between individuals of different groups?

  1. Geographical isolation

  2. Mechanical isolation

  3. Temporal isolation

  4. Hybrid sterility

  5. Behavioral isolation
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The presence of populations of a species in distant localities preventing the gene flow between them leads to geographical isolation. Different periods of attainment of sexual maturity leads to temporal isolation. Abnormal distribution to the gametes of whole chromosomes, chromosome segments, or combinations of genes leading to infertile hybrid is one of the post-zygotic isolation. Incompatible premating behavior leading to no attraction between groups for mating is termed as behavioral isolation. Incompatible differences in reproductive structures leading to prevention of cross-fertilization refer to as mechanical isolation. 

Therefore, the correct answer is option B.

Multiple choice biology selection and evolution theory of natural selection natural selection evidence for evolution

What's the difference between genetic drift and change due to natural selection?

  1. Genetic drift does not require the presence of variation.

  2. Genetic drift does not involve competition between members of a species.

  3. Genetic drift never occurs in nature, natural selection does.

  4. There is no difference.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Genetic drift is a random process that changes allele frequencies in a population due to chance events, independent of the fitness of the individuals. Natural selection, conversely, is driven by the differential survival and reproduction of individuals based on their traits, which inherently involves competition.

Multiple choice biology selection and evolution theory of natural selection natural selection evidence for evolution

Choose the correct answers from the alternatives given.
............ sometimes occurs in situations where individuals of two previously isolated demes come back into sympatry.

  1. heterosis

  2. character displacement

  3. truncation selection

  4. frequency-dependent selection
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Character displacement is the term used to describe an evolutionary change that occurs when two similar species inhabit the same environment. This due to the geographical isolation.

So correct option is B, character displacement.

Multiple choice biology improvement in food resources crop variety improvement improvement if crop varieties improvement in crop variety

Which of the following is not applicable to biological species concept?

  1. Hybridisation

  2. Reproductive isolation

  3. Natural selection

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

Answer is option A i.e. "Hybridisation"
The biological species concept defines a species as members of populations that interbreed in nature. According to this concept, organisms belong to the same species if they can interbreed to produce viable, fertile offspring. Reproductive isolation, natural selection and gene pool are applicable to one species.
Hybridisation, on contrary, occurs due to process of combining two different species of organisms to create a hybrid.
Hence, "hybridisation" is not applicable to biological species concept.

Multiple choice zoology environmental factors environmental factors and their measurements climate factors marine life

Which of the following is an example of environmental variation?

  1. Apu is a tongue roller, but his brother Sanjay is not.

  2. Marge dyes her hair blue.

  3. Homer inherited baldness from his father's side of the family.

  4. Patti and Selma have hanging ear lobes.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Environmental variation refers to differences in traits caused by external factors rather than genetics. Dyeing hair is an acquired trait influenced by the environment, not inherited.