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 biology pollination, fertilization and development of endosperm and embryo types of pollination cross pollination pollination and its types

Advantage of cleistogamy is ..................

  1. More vigorous offspring

  2. Non-dependence on pollinators

  3. Vivipary

  4. Higher genetic variability
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Cleistogamy procedure do not depend on pollinators. It is because, cleistogamy is automatic self-pollination which describes the trait of certain plants to propagate by using non-opening, self-pollinating flowers. Especially well known in peanuts, peas and beans, this behaviour is most widespread in the grass family.

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

An advantage of cleistogamy is

  1. It leads to greater genetic diversity.

  2. Seed dispersal is more efficient and wide spread.

  3. Each visit of pollinator brings hundreds of pollen grains.

  4. Seed set is not dependent upon pollinators.
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
Cleistogamy is the phenomenon, where flowers never open and in such flowers, only self-pollination occurs within the bud (unopened flower). Bisexual flowers which do not open at all are called cleistogamous. In such flowers, anthers and stigma lie close to each other. When the anthers dehisce in the flower buds, pollen grains come in contact with the stigma and pollination occurs. Cleistogamous flowers are not dependent on external agencies for pollination. Hence, seed setting is not dependent on pollinators and will occur even in the absence of pollinators.
So, the correct answer is D.
Multiple choice botany adaptation plant adaptation adaptation in plants plant habitat importance and classification of angiosperms aquatic plant adaptations pollination through water life in water

Study of genetic composition of population in relation to habitat is called

  1. Genecology

  2. Genetics

  3. Eugenics

  4. Euthenics
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
a) Genecology is a branch of ecology which studies genetic variation of species compared to their population distribution in a particular environment.
b) Genetics is the branch of zoology which deals with the mechanism of heredity. It deals with transmission of hereditary characters from parents to offspring. 
c) Eugenics is the branch of science which deals with the selection of desired heritable characteristics in order to improve future generations.
d) Euthenics is the science of improving the internal well-being of the human by improving the external factor of their environment. 
So, the correct answer is 'Genecology'.
Multiple choice zoology immunity phagocytosis cells in immune system immune system, its cells, mediators and antigens

Clonal selection involves 

  1. Change in gene frequency

  2. Proliferation of T and B-cell

  3. Formation of dolly sheep

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

Clonal selection is a process to determine how B or T cell recognizes an antigen that enters the body is selected from the per-existing cell pool of differing antigen specificities and its proliferation to generate a clonal cell population that eliminates the antigen.
Thus, the correct answer is option B.

Multiple choice zoology living and non living characteristics of life attributes of living organisms signs of life biology : an introduction living world and classification

There are various types of reproduction. The type of reproduction adopted by an organism depends on

  1. The habitat and morphology of the organism

  2. Morphology of the organism

  3. Morphology and physiology of the organism

  4. The organisms habitat, physiology and genetic makeup
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
There are various types of reproduction, both asexual (fission, budding, etc.) and sexual (internal and external). The type of reproduction, an organism undergoes depends ultimately on its genetic makeup which influences its physiology. Habitat also influence the type of reproduction, that organism undergoes.
So, the correct answer is 'The organisms habitat, physiology and genetic makeup'.
Multiple choice zoology reproduction in organisms parthenocarpic fruits parthenogenesis the life cycle of plants

In apomictic/parthenogenetic development the individuals are

  1. Morphologically and genetically similar

  2. Morphologically and genetically different

  3. Morphologically similar but genetically different

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

Development of an embryo from an unfertilized egg cell is called as parthenogenesis. The offsprings produced through apomictic are similar in morphological and genetical characters.

So the correct answer is 'Morphologically and genetically similar.'

Multiple choice organization of commerce and management recruitment methods meaning, nature, methods and sources of recruitment meaning, sources and methods of recruitment meaning and definition of recruitment

Bone of contention, inbreeding are ________ .

  1. merits of recruitment

  2. demerits of recruiment

  3. source of recruitment

  4. methods of recruitment
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Bone of contention (conflict) and inbreeding (hiring from limited pools) are recognized demerits of recruitment practices that can harm organizational effectiveness. These issues create internal friction and reduce diversity. They are not merits, sources, or methods but rather negative consequences.

Multiple choice zoology biodiversity, classification and conservation levels of biodiversity environmental conservation and biodiversity biodiversity on earth and in india

Which of the following ways is most likely to decrease the genetic diversity in a population?

  1. Gene mutation

  2. Genetic recombination

  3. Stabilising natural selection

  4. Immigration of individuals
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
  • Genetic diversity is the total number of genetic characteristics in the genetic makeup of a species. For example, The genetic diversity shown by the medicinal plant Rauwolfia vomitoria growing in different Himalayan ranges might be in terms of the potency and concentration of the active chemical (reserpine) that the plant produces. 
  • Genetic variation is an important force in evolution as it allows natural selection to increase or decrease the frequency of alleles already in the population.
  • Stabilizing natural selection is most likely to decrease the genetic diversity in a population because the frequency of alleles remains constant in stabilized natural selection.
  • So, the correct answer is 'Stabilising natural selection'.
Multiple choice zoology biodiversity, classification and conservation levels of biodiversity environmental conservation and biodiversity biodiversity on earth and in india

Which of the following is incorrectly matched?

  1. Alpha diversity Number of species in a given habitat

  2. Genetic diversity Variation of genes within species

  3. Beta-diversity - Diversity of habitat in the whole region

  4. Species diversity - The product of species richness and evenness
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
Genetic diversity is the total number of genetic characteristics in the genetic makeup of a species. It is distinguished from genetic variability, which describes the tendency of genetic characteristics to vary. Genetic diversity serves as a way for populations to adapt to changing environments. With more variation, it is more likely that some individuals in a population will possess variations of alleles that are suited for the environment. Those individuals are more likely to survive to produce offspring bearing that allele. The population will continue for more generations because of the success of these individuals. The academic field of population genetics includes several hypotheses and theories regarding genetic diversity. The neutral theory of evolution proposes that diversity is the result of the accumulation of neutral substitutions. Diversifying selection is the hypothesis that two subpopulations of a species live in different environments that select for different alleles at a particular locus. This may occur, for instance, if a species has a large range relative to the mobility of individuals within it. Frequency-dependent selection is the hypothesis that as alleles become more common, they become more vulnerable. This occurs in host–pathogen interactions, where a high frequency of a defensive allele among the host means that it is more likely that a pathogen will spread if it is able to overcome that allele.
So the correct option is 'genetic diversity- variation of genes within species'.
Multiple choice zoology biodiversity, classification and conservation levels of biodiversity environmental conservation and biodiversity biodiversity on earth and in india

Which evolutionary force decreases the genetic diversity of a population by increasing the proportion of smaller individuals?

  1. Mutation

  2. Gene flow

  3. Bottle neck effect

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

The bottleneck effect occurs when a population's size is drastically reduced, leading to loss of genetic diversity as only certain individuals survive and reproduce. This reduces the gene pool. Mutation increases diversity, gene flow can increase diversity by introducing new alleles, and random mating maintains Hardy-Weinberg equilibrium.

Multiple choice zoology biodiversity, classification and conservation levels of biodiversity environmental conservation and biodiversity biodiversity on earth and in india

Genetic diversity will be more common in organisms with 

  1. Parthenogenesis

  2. Sexual reproduction

  3. Asexual reproduction

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

Genetic diversity refers to the variety of genes within a species. Each species is made up of individuals, that have their own particular genetic composition. Within a species there may also be discrete populations with distinctive genes. 

Asexual reproduction results in no new gene configurations, so the offspring is genetically identical to the parent. 
Sexual reproduction results in an offspring, that receives genes from two parents. The advantage of sexual reproduction occurs when the two parents come from different populations. This way the genetic info is the combination of two parents from two separate populations. This is why young male lions are kicked out of the pride and why it is illegal to marry your cousin, as this insures genetic diversity.

Multiple choice zoology biodiversity, classification and conservation levels of biodiversity environmental conservation and biodiversity biodiversity on earth and in india

How does the genetic diversity of a modern corn field compare to the genetic diversity of a population of the pre-domesticated corn plant?

  1. Less diversity

  2. More diversity

  3. More genetic diversity, but less phenotypic variation

  4. The same amount of diversity
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The genetic diversity of a modern corn field is more diverse as it may contain genes transferred from from bacteria, to naturally protect it from pests 

For example, Bt corn
However, a pre domesticated corn plant is the one that is most suitable to be grown in a certain environment, majorly by artificial selection that is cross breeding and deriving a gene pool from an existing one that can provide a better commercial value
Example - sweet corn, a recessive trait, but is abundantly available due to taste preference and comparatively soft kernels

Multiple choice zoology biodiversity, classification and conservation levels of biodiversity environmental conservation and biodiversity biodiversity on earth and in india

Write the correct sequence of genetic diversity.

  1. Kingdom $\rightarrow$ species $\rightarrow $chromosomes$ \rightarrow $genes $\rightarrow$ nucleotides
  2. Population $\rightarrow$species $\rightarrow$ chromosomes $\rightarrow$ genes $\rightarrow$ nucleotides.
  3. Species $\rightarrow$ genes $\rightarrow$population $\rightarrow $ chromosomes$ \rightarrow $ nucleotides
  4. Kingdom $ \rightarrow$ population $\rightarrow$ species $\rightarrow$ genes $\rightarrow$ chromosome $\rightarrow$ nucleotides
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Genetic diversity is the diversity in the number and types of genes as well as chromosomes present in different species and variations in the gene and their alleles in the same species.
Population $\rightarrow $Species $\rightarrow $Chromosomes $\rightarrow $Genes $\rightarrow $Nucleotide is the correct sequence of genetic diversity.

Multiple choice zoology biodiversity, classification and conservation levels of biodiversity environmental conservation and biodiversity biodiversity on earth and in india

A species spread over a large tract with varied environmental conditions will have

  1. Higher genetic diversity

  2. Uniform gene pool

  3. Little genetic diversity

  4. Either B or C
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The variety and variability of living organisms (both plants and animals) are known as biodiversity. The variation measured by biodiversity is at the genetic, species, and ecosystem level. Gene-based diversity is known as genetic diversity. It is a way for populations to adapt to changing environments. A species spread over a large tract with varied environmental conditions will have higher genetic diversity.

So, the correct answer is 'Higher genetic diversity'.

Multiple choice zoology biodiversity, classification and conservation levels of biodiversity environmental conservation and biodiversity biodiversity on earth and in india

In India, we find mangoes with different flavours, colours, fibre content, sugar content and shelf life. The large variation is due to 

  1. Genetic diversity

  2. Species diversity

  3. Induced mutations

  4. Hybridisation
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
Genetic diversity represents the total number of genetic characteristics in the genetic makeup of a species. Whereas, the genetic variability describes the tendency of genetic characteristics to vary. This diversity lets the population adapt to changing environments. For example, In India, we find mangoes with different flavors, colors, fiber content, sugar content and shelf life. The great variation is due to the genetic diversity.
So, the correct answer is 'Genetic diversity'.