MCQ Bank
What was one major characteristic of Earth’s early atmosphere?
- A) It was covered with forests
- B) It was rich in oxygen
- C) It supported complex life
- D) It lacked oxygen
What did the Miller-Urey experiment demonstrate?
- A) Oxygen is needed to create amino acids
- B) DNA can be created from rocks
- C) Organic compounds can form under early Earth conditions
- D) Hydrothermal vents were unimportant
Fossils show that:
- A) Life on Earth was different in the past
- B) Life has always existed in its present form
- C) Evolution only affects plants
- D) Extinct organisms had no relation to modern ones
Which method is considered the gold standard for determining allele frequency?
- A) Genotyping approach
- B) Phenotypic observation
- C) DNA fingerprinting
- D) PCR only
How does natural selection affect allele frequencies in a population?
- A) It only increases harmful alleles
- B) It removes all alleles
- C) It increases the frequency of beneficial alleles
- D) It ensures all alleles are equally common
What does a phylogenetic tree represent?
- A) Ecosystem structure
- B) A food chain
- C) Geographical distribution
- D) Evolutionary relationships
What is convergent evolution?
- A) Independent evolution of similar traits in unrelated species
- B) Similar evolution in genetically identical species
- C) Evolution of dissimilar traits in similar environments
- D) Evolution from a common ancestor
In a heterozygous genotype (2pq), which allele dominates the phenotype if p is dominant and q is recessive?
- A) Both alleles
- B) Neither allele
- C) q allele
- D) p allele
Why can chromosomal mutations affect two chromosomes in translocation?
- A) They separate completely
- B) Mutation is neutral
- C) One loses and one gains a segment
- D) One becomes smaller
The forelimbs of a human, bird, whale, and dog are examples of:
- A) Homologous structures
- B) Degenerate organs
- C) Convergent features
- D) Homoplastic structures
Which process can create new alleles in a population?
- A) Photosynthesis
- B) Digestion
- C) Mutation
- D) Breathing
Where are fossils mostly preserved?
- A) Sedimentary rocks
- B) Igneous rocks
- C) Metamorphic rocks
- D) Volcanic layers
What does the Modern Synthetic Theory of Evolution primarily explain?
- A) Evolution only by environmental influence
- B) Evolution through use and disuse
- C) Evolution through genetic variations and natural selection
- D) Evolution of planets
The bottleneck effect occurs when:
- A) A mutation arises in a single allele
- B) A species migrates to a new habitat
- C) A large population is genetically modified
- D) Population size is drastically reduced for at least one generation
Which molecule is referred to as a universal code among organisms?
- A) ATP
- B) Enzyme
- C) RNA
- D) DNA
What are fossils?
- A) Remains or imprints of dead organisms
- B) Living organisms in deep oceans
- C) Crystals formed in rocks
- D) Artificial models of ancient animals
What do fossils primarily provide evidence for?
- A) Biodiversity in current ecosystems
- B) Evolutionary changes over time
- C) Photosynthesis in plants
- D) Earth's atmospheric composition
What does the green dot represent in the frog population example?
- A) Frogs with green skin color
- B) Frogs with multiple alleles
- C) Frogs with dominant traits
- D) Frogs that are extinct
In a population, what is indicated when the Hardy-Weinberg equilibrium is not maintained?
- A) The population is stable
- B) There is no gene flow
- C) Evolution is occurring
- D) The population is shrinking
What is the main difference between microevolution and macroevolution?
- A) Size of organism
- B) Environment
- C) Time scale over which it occurs
- D) Location of evolution