Question
A central idea in the theory of evolution is that species may evolve gradually over time from a common ancestor.
Which statement(s) explain(s) the pattern of evolution seen in the diagram?
I. Beak shape shows genetic variability in the common ancestor.
II. Changes in beak shape that occur during the lifetime of an individual bird are passed on to the next generation.
III. Changes in beak shape are heritable and make each species better adapted to its environment.
A. II only
B. I and II only
C. I and III only
D. I, II and III
▶️Answer/Explanation
Ans. C
Question
The cladogram shows the evolutionary relationships between a number of animal groups.
What can be concluded from this cladogram?
A. Tuna evolved from sharks.
B. Crocodiles are more closely related to birds than to whales.
C. Frogs, humans and whales do not share a common ancestor.
D. Shark and tuna evolved later than humans
▶️Answer/Explanation
Ans. B
Darwin described evolution as “descent with modification”. What would make evolution less probable?
A. Stable environment
B. Migration
C. Variation in offspring
D. Random mutation
Answer/Explanation
Markscheme
A
What causes heritable variation in a species?
I. Muscle development through exercise
II. Increased rainfall in the ecosystem
III. Changes in the genome of the species
A. I and III only
B. II only
C. III only
D. I, II and III
Answer/Explanation
Markscheme
C
The long-term exposure of bacteria to antibiotics has led to the spread of resistant strains (for example, of Clostridium difficile). What is this an example of?
A. Convergent evolution
B. Immunity
C. Natural selection
D. Dominance
Answer/Explanation
Markscheme
C
Question
What is an outcome of natural selection?
A. Evolution
B. Mutations
C. Reproductive isolation
▶️Answer/Explanation
D. Variation
Question
What is required for natural selection to occur?
I. Acquired characteristics
II. Advantageous characteristics
III. Genetic variation
A. I only
B. I and III only
C. II and III only
D. I, II and III
▶️Answer/Explanation
C