Questions & Answers/Latest Updated
Module 1: Evolution and Biodiversity
1. Which of the following is the ultimate source of all genetic variation?
• A) Sexual reproduction
• B) Natural selection
• C) Mutations
• D) Genetic drift
Correct Answer: C) Mutations
Rationale: Mutations are changes in DNA sequences that create new alleles. They
are the original source of all genetic variation upon which natural selection and
other evolutionary forces act. Sexual reproduction reshuffles existing variation but
does not create new alleles.
2. The biological species concept defines a species as:
• A) Organisms that look similar in structure
• B) Organisms that share similar DNA sequences
• C) Populations that interbreed in nature to produce fertile offspring
• D) Organisms that occupy the same ecological niche
,Correct Answer: C) Populations that interbreed in nature to produce fertile
offspring
Rationale: The biological species concept emphasizes reproductive isolation.
Populations are considered separate species if they do not interbreed in nature or
cannot produce fertile offspring. This concept focuses on gene flow between
populations.
3. Which type of phylogenetic group includes an ancestral species and ALL of its
descendants?
• A) Polyphyletic group
• B) Paraphyletic group
• C) Monophyletic group (clade)
• D) Analogous group
Correct Answer: C) Monophyletic group (clade)
Rationale: A monophyletic group (clade) consists of an ancestral species and all of
its evolutionary descendants. This is the only grouping that accurately reflects
evolutionary relationships and common ancestry. Polyphyletic groups include
organisms from different evolutionary lineages.
4. Which of the following is NOT a requirement for Hardy-Weinberg equilibrium?
• A) Large population size
, • B) No mutations
• C) Random mating
• D) Natural selection occurring
Correct Answer: D) Natural selection occurring
Rationale: Hardy-Weinberg equilibrium requires NO evolutionary forces acting on
the population: no natural selection, no mutations, no genetic drift, no gene flow,
and random mating. If natural selection is occurring, allele frequencies will change
over generations, violating equilibrium.
5. What is the correct order of Linnaean taxonomic ranks from broadest to most
specific?
• A) Domain, Kingdom, Phylum, Class, Order, Family, Genus, Species
• B) Species, Genus, Family, Order, Class, Phylum, Kingdom, Domain
• C) Kingdom, Domain, Phylum, Class, Order, Family, Genus, Species
• D) Domain, Phylum, Kingdom, Class, Order, Family, Genus, Species
Correct Answer: A) Domain, Kingdom, Phylum, Class, Order, Family, Genus,
Species
Rationale: The Linnaean classification system organizes organisms into a hierarchy
of increasingly specific groups. The mnemonic "Dear King Philip Came Over For
Good Soup" helps remember the order: Domain, Kingdom, Phylum, Class, Order,
Family, Genus, Species.
, 6. Which type of structure indicates common ancestry between different
species?
• A) Analogous structures
• B) Homologous structures
• C) Vestigial structures
• D) Convergent structures
Correct Answer: B) Homologous structures
Rationale: Homologous structures are anatomically similar structures that evolved
from a common ancestor, though they may serve different functions. Examples
include the forelimbs of mammals (human arm, whale flipper, bat wing).
Analogous structures result from convergent evolution and do not indicate
common ancestry.
7. The Cambrian Explosion refers to:
• A) The first appearance of life on Earth
• B) The sudden appearance of diverse animal fossils with hard parts
• C) The evolution of flowering plants
• D) The extinction of the dinosaurs
Correct Answer: B) The sudden appearance of diverse animal fossils with hard
parts