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Secondary 3 Biology Evolution Diversity Quiz
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Questions
Secondary 3 Biology Quiz - Evolution Diversity
Name: _________________________ Class: _________________________ Date: _________________________ Score: _________ / 40
Duration: 45 minutes Total Marks: 40
Instructions:
- Answer ALL questions in the spaces provided.
- Write your answers clearly and legibly.
- The marks for each question or part-question are shown in brackets.
- Use appropriate biological terminology in your responses.
Section A: Multiple Choice (5 marks)
Choose the most appropriate answer for each question. Write the letter (A, B, C, or D) in the box provided.
1. Which of the following provides the strongest evidence that two different species share a recent common ancestor?
A) They live in the same habitat. B) They have similar body sizes. C) They have a high degree of similarity in their DNA sequences. D) They are both preyed upon by the same predator.
[ ] [1 mark]
2. The wings of a bat and the wings of an insect are considered analogous structures. What does this indicate about their evolutionary relationship?
A) They evolved from a common winged ancestor. B) They evolved independently as adaptations for flight. C) The bat wing is a more advanced version of the insect wing. D) They are homologous structures that have diverged over time.
[ ] [1 mark]
3. In a population of snails, shell colour varies from light to dark. Birds are the main predators and can spot light-coloured snails more easily on dark rocks. Over many generations, the population becomes mostly dark-shelled. This is an example of:
A) Artificial selection B) Genetic drift C) Natural selection D) Use and disuse
[ ] [1 mark]
4. Which statement best describes the theory of evolution by natural selection?
A) Organisms develop new traits because they need them to survive. B) Individuals with traits better suited to their environment are more likely to survive and reproduce. C) All individuals in a population are equally likely to survive and reproduce. D) Evolution always results in more complex organisms.
[ ] [1 mark]
5. The appendix in humans is a small, functionless remnant of a larger organ found in herbivorous ancestors. The appendix is an example of:
A) An analogous structure B) A homologous structure C) A vestigial structure D) An adaptive radiation
[ ] [1 mark]
Section B: Structured Questions (25 marks)
Answer all questions in the spaces provided.
6. The diagram below shows the forelimb bones of four different vertebrates: a human, a cat, a whale, and a bat.
[Diagram description: Four forelimb skeletons are shown. Each has a similar arrangement of bones: one upper bone (humerus), two lower bones (radius and ulna), a group of small wrist bones (carpals), and five digits (metacarpals and phalanges). The shapes and sizes of the bones differ among the organisms.]
(a) Identify the type of structures represented by the forelimbs of these four vertebrates. [1 mark]
(b) Explain how these structures provide evidence for evolution. [2 marks]
(c) State one reason why the forelimbs of these vertebrates have different shapes and sizes, despite having a similar basic bone arrangement. [1 mark]
7. The peppered moth (Biston betularia) exists in two main forms: a light-coloured (peppered) form and a dark-coloured (melanic) form. Before the Industrial Revolution in England, the light form was much more common. During the Industrial Revolution, tree trunks became darkened by soot, and the dark form became more common.
(a) Explain why the light-coloured form was more common before the Industrial Revolution. [2 marks]
(b) Explain how natural selection led to the increase in the dark-coloured form during the Industrial Revolution. [3 marks]
(c) State one source of the genetic variation that produced the dark form in the moth population. [1 mark]
8. The table below shows the percentage difference in the DNA sequence of a particular gene among four species (A, B, C, and D).
| Species Pair | Percentage Difference in DNA (%) |
|---|---|
| A and B | 2.5 |
| A and C | 8.1 |
| A and D | 15.3 |
| B and C | 7.9 |
| B and D | 14.8 |
| C and D | 12.6 |
(a) Based on the data, which two species are most closely related? Explain your answer. [2 marks]
(b) Construct a simple branching diagram (cladogram) to show the evolutionary relationships among species A, B, C, and D. Label each branch tip with the species letter. [3 marks]
[Draw your diagram in the space below]
(c) Explain why comparing DNA sequences is a more reliable method for determining evolutionary relationships than comparing physical characteristics alone. [2 marks]
9. Antibiotic resistance in bacteria is a growing global health concern. When antibiotics are used, most bacteria are killed, but some may survive due to existing genetic variations that confer resistance.
(a) Explain how a population of bacteria can become resistant to an antibiotic over time through natural selection. [3 marks]
(b) Suggest one reason why doctors advise patients to complete the full course of prescribed antibiotics, even if they feel better. [2 marks]
10. The Galapagos finches, studied by Charles Darwin, have beaks of different shapes and sizes adapted to different food sources on the islands.
(a) Explain how the different beak shapes among the finch species could have arisen from a common ancestral finch population. [3 marks]
Section C: Data-Based Question (10 marks)
Read the following information and answer the questions that follow.
11. The graph below shows the distribution of beak depths in a population of medium ground finches (Geospiza fortis) on Daphne Major Island in the Galapagos. The data were collected in 1976 (before a severe drought) and in 1978 (after the drought). During the drought, the only seeds available were large, hard seeds that required a deep beak to crack open.
[Graph description: Two histograms showing beak depth distribution. The 1976 graph shows a normal distribution centred around 9.5 mm, ranging from 7.5 mm to 11.5 mm. The 1978 graph shows a similar range but the distribution is shifted to the right, centred around 10.5 mm, with fewer birds having beak depths below 9.0 mm.]
(a) Describe the change in the distribution of beak depths from 1976 to 1978. [2 marks]
(b) Explain how the drought acted as a selection pressure on the finch population. [3 marks]
(c) Predict what might happen to the beak depth distribution if several years of heavy rainfall followed the drought, producing an abundance of small, soft seeds. Explain your prediction. [3 marks]
(d) The finch population did not become extinct during the drought. Suggest why the population was able to survive despite the drastic change in food availability. [2 marks]
Section D: Application and Analysis (10 marks)
Answer all questions in the spaces provided.
12. Define the term "natural selection" and state two conditions necessary for it to occur. [3 marks]
13. Explain how the fossil record provides evidence for the theory of evolution. [2 marks]
14. The cheetah population has very low genetic variation due to a severe population bottleneck in the past. Explain one potential disadvantage of low genetic variation for the long-term survival of the cheetah species. [2 marks]
15. A farmer repeatedly uses the same pesticide on a crop to control insect pests. Initially, the pesticide is very effective, but after several years, it becomes less effective. Using your knowledge of natural selection, explain how the insect population has evolved resistance to the pesticide. [3 marks]
16. Distinguish between homologous structures and analogous structures, providing one example of each. [2 marks]
17. Explain why the statement "Humans evolved from chimpanzees" is scientifically inaccurate. [2 marks]
18. Describe how geographic isolation can lead to the formation of new species (speciation). [3 marks]
19. The wings of a penguin and the wings of an eagle are homologous structures, yet they are used for different functions (swimming vs. flying). Explain how homologous structures can have different functions. [2 marks]
20. A scientist discovers a new species of lizard on a remote island. Suggest two types of evidence the scientist could collect to determine the evolutionary relationship between this new lizard species and lizards on the mainland. [2 marks]
Answers
Secondary 3 Biology Quiz - Evolution Diversity: ANSWER KEY
Total Marks: 40
Section A: Multiple Choice (5 marks)
1. C) They have a high degree of similarity in their DNA sequences. [1 mark] Marking note: DNA similarity is the most direct and reliable molecular evidence for common ancestry. Accept C only.
2. B) They evolved independently as adaptations for flight. [1 mark] Marking note: Analogous structures arise from convergent evolution, not common ancestry. Accept B only.
3. C) Natural selection [1 mark] Marking note: The scenario describes differential survival based on heritable variation in shell colour due to predation pressure. Accept C only.
4. B) Individuals with traits better suited to their environment are more likely to survive and reproduce. [1 mark] Marking note: This is the core definition of natural selection. Accept B only.
5. C) A vestigial structure [1 mark] Marking note: A vestigial structure is a remnant of an organ that had a function in an ancestor but is reduced or functionless in the current organism. Accept C only.
Section B: Structured Questions (25 marks)
6. (a) Homologous structures. [1 mark] Accept: Structures that share a common basic plan/ancestry.
(b) Award up to 2 marks for:
- The forelimbs have a similar basic bone arrangement/pentadactyl limb structure [1 mark]
- This suggests they evolved from a common ancestor that possessed this basic limb structure [1 mark] Accept: The similarity in structure indicates divergent evolution from a common ancestor; the differences are due to adaptation to different functions/environments.
(c) Award 1 mark for:
- They are adapted for different functions (e.g., grasping in humans, swimming in whales, flying in bats, running in cats) / They live in different environments and have different modes of locomotion. Accept any reasonable explanation linking different functions/environments to different shapes.
7. (a) Award up to 2 marks for:
- Tree trunks were light-coloured/covered with lichen before the Industrial Revolution [1 mark]
- Light-coloured moths were camouflaged against the light tree trunks, making them less visible to predators (birds) [1 mark] Accept: Light moths had higher survival rate because they were better camouflaged.
(b) Award up to 3 marks for:
- Variation existed in the moth population (light and dark forms) [1 mark]
- When tree trunks became darkened by soot, dark moths were better camouflaged and less likely to be eaten by birds / light moths were more visible and more likely to be eaten [1 mark]
- Dark moths survived to reproduce and pass on their alleles/genes for dark colour to offspring; over generations, the proportion of dark moths increased [1 mark] Accept any clear description of the natural selection process: variation → selection pressure → differential survival → reproduction → change in population.
(c) Award 1 mark for:
- Mutation / random change in DNA/gene. Accept: Genetic mutation in the gene controlling wing colour.
8. (a) Award up to 2 marks for:
- Species A and B are most closely related [1 mark]
- They have the lowest percentage difference in DNA (2.5%), indicating the most recent common ancestor [1 mark] Accept: The smaller the DNA difference, the more closely related the species.
(b) Award up to 3 marks for:
- Correct branching order showing A and B as sister groups (branching from the most recent common ancestor) [1 mark]
- C branching off next (sharing a more distant common ancestor with A and B) [1 mark]
- D branching off first (sharing the most distant common ancestor with the other three) [1 mark]
Example acceptable cladogram:
┌─── A
┌─┤
│ └─── B
──┤
│ ┌─── C
└─┤
└─── D
Marking note: The order of branching must reflect the DNA difference data. A and B must be closest; D must be the outgroup (most distant). Award marks for correct topology, not artistic quality.
(c) Award up to 2 marks for:
- DNA sequences provide a direct record of evolutionary changes/mutations over time [1 mark]
- Physical characteristics can be influenced by environmental factors/convergent evolution, which may lead to misleading similarities (analogous structures) / DNA is less subject to convergent evolution [1 mark] Accept: DNA analysis is more objective and quantifiable; physical traits can be similar due to similar environments rather than common ancestry.
9. (a) Award up to 3 marks for:
- Genetic variation exists in the bacterial population; some bacteria possess alleles/genes that confer resistance to the antibiotic [1 mark]
- When the antibiotic is applied, it acts as a selection pressure: non-resistant bacteria are killed, while resistant bacteria survive [1 mark]
- Resistant bacteria reproduce and pass on the resistance alleles to their offspring; over generations, the proportion of resistant bacteria in the population increases [1 mark] Accept any clear natural selection explanation applied to antibiotic resistance.
(b) Award up to 2 marks for:
- Stopping early may leave some bacteria alive (especially those with partial resistance) [1 mark]
- These surviving bacteria can reproduce and the infection may return, and the bacteria may be more resistant to the antibiotic in future [1 mark] Accept: Completing the course ensures all bacteria are killed, reducing the chance of resistance developing.
10. (a) Award up to 3 marks for:
- The ancestral finch population showed variation in beak size and shape [1 mark]
- On different islands, different food sources were available; finches with beak shapes best suited to the available food had higher survival and reproductive success [1 mark]
- Over many generations, natural selection led to the divergence of the population into different species with distinct beak shapes adapted to specific food sources (adaptive radiation) [1 mark] Accept: Geographic isolation of populations on different islands, followed by natural selection acting on beak variation in response to different food sources.
Section C: Data-Based Question (10 marks)
11. (a) Award up to 2 marks for:
- The distribution shifted to the right / towards deeper beaks [1 mark]
- The mean/peak beak depth increased from approximately 9.5 mm to 10.5 mm / fewer birds with shallow beaks (below 9.0 mm) survived [1 mark] Accept any accurate description of the shift in the histogram.
(b) Award up to 3 marks for:
- The drought caused a shortage of small seeds; only large, hard seeds were available [1 mark]
- Finches with deeper beaks could crack open the large, hard seeds and obtain food [1 mark]
- Finches with shallower beaks could not feed effectively and died; deeper-beaked finches survived and reproduced, passing on their alleles for deep beaks [1 mark] Accept: The drought changed the food availability, favouring finches with deep beaks (directional selection).
(c) Award up to 3 marks for:
- The beak depth distribution would likely shift back towards shallower beaks / the mean beak depth would decrease [1 mark]
- An abundance of small, soft seeds would favour finches with smaller/shallower beaks, as they may be more efficient at handling small seeds [1 mark]
- Finches with smaller beaks would have higher survival and reproductive success, increasing the frequency of alleles for smaller beaks in the population [1 mark] Accept any reasonable prediction with explanation based on natural selection principles. Award marks for linking the change in food availability to a change in selection pressure and predicted evolutionary response.
(d) Award up to 2 marks for:
- There was variation in beak depth in the population; some individuals had deep enough beaks to survive [1 mark]
- These survivors reproduced and maintained the population / the population had sufficient genetic diversity to allow some individuals to survive the changed conditions [1 mark] Accept: Not all finches died; the survivors passed on their genes for deeper beaks, allowing the population to recover.
Section D: Application and Analysis (10 marks)
12. Award up to 3 marks for:
- Natural selection is the process whereby organisms better adapted to their environment tend to survive and produce more offspring [1 mark]
- Condition 1: There must be variation in traits within a population [1 mark]
- Condition 2: The variation must be heritable / There must be differential survival and reproduction based on the traits / There must be a selection pressure [1 mark] Accept any two valid conditions. Award marks for accurate definition and conditions.
13. Award up to 2 marks for:
- The fossil record shows a chronological sequence of organisms, with simpler forms in older rocks and more complex forms in younger rocks [1 mark]
- It shows transitional forms/intermediate species that link different groups, indicating gradual change over time [1 mark] Accept: Fossils show that organisms have changed over time; extinct species are found that are different from modern species.
14. Award up to 2 marks for:
- Low genetic variation means the population has less ability to adapt to environmental changes/new diseases [1 mark]
- If a new disease or environmental change occurs, there may be few or no individuals with resistant/adaptive alleles, leading to possible extinction [1 mark] Accept: Reduced evolutionary potential; inbreeding depression; accumulation of harmful recessive alleles.
15. Award up to 3 marks for:
- Variation existed in the insect population; some insects possessed alleles/genes that conferred resistance to the pesticide [1 mark]
- When the pesticide was applied, it killed susceptible insects, but resistant insects survived (selection pressure) [1 mark]
- Resistant insects reproduced and passed on resistance alleles to offspring; over generations, the frequency of resistance alleles increased, making the pesticide less effective [1 mark] Accept any clear natural selection explanation applied to pesticide resistance.
16. Award up to 2 marks for:
- Homologous structures share a common ancestral origin but may have different functions (e.g., forelimbs of vertebrates) [1 mark]
- Analogous structures have similar functions but different ancestral origins/evolved independently (e.g., wings of birds and insects) [1 mark] Accept any valid examples. Award 1 mark for each correct distinction with example.
17. Award up to 2 marks for:
- Humans and chimpanzees share a common ancestor; they did not evolve directly from one another [1 mark]
- Both lineages evolved separately from that common ancestor millions of years ago [1 mark] Accept: The evolutionary relationship is like a branching tree, not a linear chain.
18. Award up to 3 marks for:
- A population becomes separated by a geographic barrier (e.g., mountain, river, ocean) [1 mark]
- The separated populations experience different environmental conditions/selection pressures and accumulate different mutations [1 mark]
- Over many generations, the populations diverge genetically to the point where they can no longer interbreed to produce fertile offspring, forming new species [1 mark] Accept any clear description of allopatric speciation.
19. Award up to 2 marks for:
- Homologous structures share a common ancestral origin but have evolved different shapes and functions due to adaptation to different environments/ways of life [1 mark]
- The penguin wing adapted for swimming in water, while the eagle wing adapted for flying in air; both evolved from the forelimb of a common ancestor [1 mark] Accept: Divergent evolution leads to homologous structures with different functions.
20. Award up to 2 marks for:
- Compare DNA sequences / genetic analysis of the island lizard and mainland lizards [1 mark]
- Compare physical characteristics/morphology / Compare anatomical structures / Look for homologous structures [1 mark] Accept: Any two valid types of evidence (molecular, morphological, fossil, embryological). Award 1 mark per suggestion.