Q.1 Who is considered the father of evolutionary theory?
Gregor Mendel
Charles Darwin
Alfred Wallace
Thomas Hunt Morgan
Explanation - Darwin proposed natural selection as the main driving force of evolution, making him the father of evolutionary theory.
Correct answer is: Charles Darwin
Q.2 Which process introduces new genetic variation into a population?
Mutation
Selection
Drift
Migration
Explanation - Mutations are random changes in DNA sequences and are the ultimate source of new genetic variation.
Correct answer is: Mutation
Q.3 What does gene flow refer to?
Transfer of genes between populations
Random loss of alleles
Formation of new species
Mutation within DNA
Explanation - Gene flow occurs when individuals migrate and reproduce in a new population, transferring alleles.
Correct answer is: Transfer of genes between populations
Q.4 Genetic drift is most significant in:
Large populations
Small populations
Stable populations
Populations with high mutation rates
Explanation - Genetic drift is random fluctuation in allele frequencies, which has stronger effects in small populations.
Correct answer is: Small populations
Q.5 The modern synthesis combines Darwin’s theory of natural selection with:
Mendelian genetics
Lamarck’s inheritance
Cell theory
Chromosomal theory
Explanation - The modern synthesis unified Darwin’s ideas with Mendel’s genetic principles, explaining evolution in genetic terms.
Correct answer is: Mendelian genetics
Q.6 Which term describes the ability of an organism to survive and reproduce?
Adaptation
Fitness
Variation
Speciation
Explanation - In evolutionary genetics, fitness refers to reproductive success relative to others in the population.
Correct answer is: Fitness
Q.7 The Hardy-Weinberg equilibrium assumes all except:
Random mating
No mutation
No natural selection
Rapid environmental change
Explanation - Hardy-Weinberg assumes no mutation, migration, selection, and random mating in a large population. Environmental change is not part of the model.
Correct answer is: Rapid environmental change
Q.8 Which evolutionary force reduces genetic differences between populations?
Natural selection
Mutation
Genetic drift
Gene flow
Explanation - Gene flow homogenizes populations by introducing alleles from one group into another.
Correct answer is: Gene flow
Q.9 Balancing selection maintains:
Neutral mutations
Genetic diversity
Population size
Mutation rate
Explanation - Balancing selection maintains multiple alleles in a population, preserving diversity.
Correct answer is: Genetic diversity
Q.10 Which of the following is an example of a prezygotic isolation mechanism?
Hybrid sterility
Temporal isolation
Hybrid inviability
Reduced fertility
Explanation - Prezygotic isolation prevents mating or fertilization; temporal isolation occurs when species breed at different times.
Correct answer is: Temporal isolation
Q.11 Founder effect is a type of:
Mutation
Natural selection
Genetic drift
Gene flow
Explanation - Founder effect is genetic drift occurring when a new population is started by a few individuals.
Correct answer is: Genetic drift
Q.12 What is adaptive radiation?
Random genetic drift
Formation of identical traits
Diversification of a lineage into new niches
Gene flow between species
Explanation - Adaptive radiation occurs when species diversify rapidly into different ecological niches.
Correct answer is: Diversification of a lineage into new niches
Q.13 Which type of selection favors intermediate traits?
Directional
Disruptive
Stabilizing
Balancing
Explanation - Stabilizing selection favors average traits and reduces extremes.
Correct answer is: Stabilizing
Q.14 Synonymous mutations are:
Always harmful
Neutral
Beneficial
Lethal
Explanation - Synonymous mutations do not change amino acids, so they usually have no effect on fitness.
Correct answer is: Neutral
Q.15 Molecular clock hypothesis is based on:
Constant mutation rates
Natural selection
Adaptive radiation
Genetic drift
Explanation - The molecular clock assumes mutations occur at a relatively constant rate, useful for dating divergence.
Correct answer is: Constant mutation rates
Q.16 Heterozygote advantage is a form of:
Disruptive selection
Directional selection
Balancing selection
Stabilizing selection
Explanation - Heterozygote advantage maintains diversity by giving heterozygotes higher fitness (e.g., sickle-cell trait).
Correct answer is: Balancing selection
Q.17 Which scientist proposed the neutral theory of molecular evolution?
Charles Darwin
Motoo Kimura
Richard Dawkins
Ernst Mayr
Explanation - Motoo Kimura proposed that most molecular evolution is driven by neutral mutations fixed by drift.
Correct answer is: Motoo Kimura
Q.18 Speciation that occurs due to geographic separation is called:
Allopatric speciation
Sympatric speciation
Parapatric speciation
Peripatric speciation
Explanation - Allopatric speciation occurs when populations are geographically isolated and diverge genetically.
Correct answer is: Allopatric speciation
Q.19 Which evolutionary concept explains the sudden appearance of new species in the fossil record?
Gradualism
Punctuated equilibrium
Adaptive radiation
Neutral theory
Explanation - Punctuated equilibrium suggests species remain stable for long periods, with short bursts of rapid change.
Correct answer is: Punctuated equilibrium
Q.20 The bottleneck effect reduces:
Gene flow
Mutation rate
Genetic variation
Speciation rate
Explanation - Population bottlenecks drastically reduce genetic diversity due to a sharp decline in numbers.
Correct answer is: Genetic variation
Q.21 Horizontal gene transfer is most common in:
Plants
Animals
Bacteria
Fungi
Explanation - Bacteria frequently exchange genetic material via horizontal transfer, accelerating evolution.
Correct answer is: Bacteria
Q.22 Which type of selection results in two distinct phenotypes?
Directional
Stabilizing
Disruptive
Balancing
Explanation - Disruptive selection favors extreme traits, leading to two distinct phenotypic groups.
Correct answer is: Disruptive
Q.23 What is the unit of natural selection?
Population
Species
Individual
Gene
Explanation - Natural selection acts on individuals, but its consequences are seen at the population level.
Correct answer is: Individual
Q.24 Which genetic marker is often used to trace maternal lineage?
Nuclear DNA
Y chromosome
Mitochondrial DNA
Ribosomal RNA
Explanation - Mitochondrial DNA is inherited maternally and is widely used in evolutionary studies.
Correct answer is: Mitochondrial DNA
Q.25 Which evolutionary mechanism explains antibiotic resistance in bacteria?
Mutation and natural selection
Genetic drift
Stabilizing selection
Bottleneck effect
Explanation - Antibiotic resistance arises from mutations that confer survival advantage under drug pressure.
Correct answer is: Mutation and natural selection