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Weekly Format

DNA, genes, traits, Punnett squares and variation

Part A — 15 Multiple Choice

Part B — 15 Fill in the Blank

Part C — 15 Scientific Reasoning / Open Response

Part D — 5 Challenge Problems

Answers and How to Solve are separated at the end.

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Part A — Multiple Choice

Questions 1–5

1. A segment of DNA that influences a trait is a? A) gene B) an unrelated process C) none of these D) a different scientific idea

2. Different forms of a gene are called? A) alleles B) an unrelated process C) none of these D) a different scientific idea

3. An organism with two identical alleles is? A) homozygous B) an unrelated process C) none of these D) a different scientific idea

4. A Punnett square predicts? A) possible offspring genotypes B) an unrelated process C) none of these D) a different scientific idea

5. Variation in a population is important because it can? A) help populations adapt B) an unrelated process C) none of these D) a different scientific idea

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Part A — Multiple Choice

Questions 6–10

6. A segment of DNA that influences a trait is a? A) gene B) an unrelated process C) none of these D) a different scientific idea

7. Different forms of a gene are called? A) alleles B) an unrelated process C) none of these D) a different scientific idea

8. An organism with two identical alleles is? A) homozygous B) an unrelated process C) none of these D) a different scientific idea

9. A Punnett square predicts? A) possible offspring genotypes B) an unrelated process C) none of these D) a different scientific idea

10. Variation in a population is important because it can? A) help populations adapt B) an unrelated process C) none of these D) a different scientific idea

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Part A — Multiple Choice

Questions 11–15

11. A segment of DNA that influences a trait is a? A) gene B) an unrelated process C) none of these D) a different scientific idea

12. Different forms of a gene are called? A) alleles B) an unrelated process C) none of these D) a different scientific idea

13. An organism with two identical alleles is? A) homozygous B) an unrelated process C) none of these D) a different scientific idea

14. A Punnett square predicts? A) possible offspring genotypes B) an unrelated process C) none of these D) a different scientific idea

15. Variation in a population is important because it can? A) help populations adapt B) an unrelated process C) none of these D) a different scientific idea

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Part B — Fill in the Blank

Questions 16–20

16. Complete the statement: An organism with two identical alleles is ______.

17. Complete the statement: A Punnett square predicts ______.

18. Complete the statement: Variation in a population is important because it can ______.

19. Complete the statement: A segment of DNA that influences a trait is a ______.

20. Complete the statement: Different forms of a gene are called ______.

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Part B — Fill in the Blank

Questions 21–25

21. Complete the statement: An organism with two identical alleles is ______.

22. Complete the statement: A Punnett square predicts ______.

23. Complete the statement: Variation in a population is important because it can ______.

24. Complete the statement: A segment of DNA that influences a trait is a ______.

25. Complete the statement: Different forms of a gene are called ______.

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Part B — Fill in the Blank

Questions 26–30

26. Complete the statement: An organism with two identical alleles is ______.

27. Complete the statement: A Punnett square predicts ______.

28. Complete the statement: Variation in a population is important because it can ______.

29. Complete the statement: A segment of DNA that influences a trait is a ______.

30. Complete the statement: Different forms of a gene are called ______.

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Part C — Scientific Reasoning

Questions 31–35

31. A student compares two conditions and records results over five trials. Explain how the idea “alleles” is relevant. Use 2–3 complete sentences.

32. A class observes a model and explains how its parts work together. Explain how the idea “homozygous” is relevant. Use 2–3 complete sentences.

33. Students examine a data table and notice a consistent pattern. Explain how the idea “possible offspring genotypes” is relevant. Use 2–3 complete sentences.

34. A team changes one factor and measures the response. Explain how the idea “help populations adapt” is relevant. Use 2–3 complete sentences.

35. A scientist compares evidence from two possible explanations. Explain how the idea “gene” is relevant. Use 2–3 complete sentences.

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Part C — Scientific Reasoning

Questions 36–40

36. A student compares two conditions and records results over five trials. Explain how the idea “alleles” is relevant. Use 2–3 complete sentences.

37. A class observes a model and explains how its parts work together. Explain how the idea “homozygous” is relevant. Use 2–3 complete sentences.

38. Students examine a data table and notice a consistent pattern. Explain how the idea “possible offspring genotypes” is relevant. Use 2–3 complete sentences.

39. A team changes one factor and measures the response. Explain how the idea “help populations adapt” is relevant. Use 2–3 complete sentences.

40. A scientist compares evidence from two possible explanations. Explain how the idea “gene” is relevant. Use 2–3 complete sentences.

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Part C — Scientific Reasoning

Questions 41–45

41. A student compares two conditions and records results over five trials. Explain how the idea “alleles” is relevant. Use 2–3 complete sentences.

42. A class observes a model and explains how its parts work together. Explain how the idea “homozygous” is relevant. Use 2–3 complete sentences.

43. Students examine a data table and notice a consistent pattern. Explain how the idea “possible offspring genotypes” is relevant. Use 2–3 complete sentences.

44. A team changes one factor and measures the response. Explain how the idea “help populations adapt” is relevant. Use 2–3 complete sentences.

45. A scientist compares evidence from two possible explanations. Explain how the idea “gene” is relevant. Use 2–3 complete sentences.

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Part D — Challenge

Questions 46–50

46. Challenge: Design or describe a short investigation that could demonstrate the concept “gene.” Identify what you would observe or measure.

47. Challenge: Design or describe a short investigation that could demonstrate the concept “alleles.” Identify what you would observe or measure.

48. Challenge: Design or describe a short investigation that could demonstrate the concept “homozygous.” Identify what you would observe or measure.

49. Challenge: Design or describe a short investigation that could demonstrate the concept “possible offspring genotypes.” Identify what you would observe or measure.

50. Challenge: Design or describe a short investigation that could demonstrate the concept “help populations adapt.” Identify what you would observe or measure.

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Answer Key — Questions 1–5

Answer + How to Solve

1. Answer: A

How to solve: Genes are DNA sequences that contribute to traits.

2. Answer: A

How to solve: Alleles are alternative versions of a gene.

3. Answer: A

How to solve: Homozygous means the two alleles are the same.

4. Answer: A

How to solve: It models allele combinations from parents.

5. Answer: A

How to solve: Variation gives natural selection different traits to act on.

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Answer Key — Questions 6–10

Answer + How to Solve

6. Answer: A

How to solve: Genes are DNA sequences that contribute to traits.

7. Answer: A

How to solve: Alleles are alternative versions of a gene.

8. Answer: A

How to solve: Homozygous means the two alleles are the same.

9. Answer: A

How to solve: It models allele combinations from parents.

10. Answer: A

How to solve: Variation gives natural selection different traits to act on.

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Answer Key — Questions 11–15

Answer + How to Solve

11. Answer: A

How to solve: Genes are DNA sequences that contribute to traits.

12. Answer: A

How to solve: Alleles are alternative versions of a gene.

13. Answer: A

How to solve: Homozygous means the two alleles are the same.

14. Answer: A

How to solve: It models allele combinations from parents.

15. Answer: A

How to solve: Variation gives natural selection different traits to act on.

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Answer Key — Questions 16–20

Answer + How to Solve

16. Answer: homozygous

How to solve: Homozygous means the two alleles are the same.

17. Answer: possible offspring genotypes

How to solve: It models allele combinations from parents.

18. Answer: help populations adapt

How to solve: Variation gives natural selection different traits to act on.

19. Answer: gene

How to solve: Genes are DNA sequences that contribute to traits.

20. Answer: alleles

How to solve: Alleles are alternative versions of a gene.

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Answer Key — Questions 21–25

Answer + How to Solve

21. Answer: homozygous

How to solve: Homozygous means the two alleles are the same.

22. Answer: possible offspring genotypes

How to solve: It models allele combinations from parents.

23. Answer: help populations adapt

How to solve: Variation gives natural selection different traits to act on.

24. Answer: gene

How to solve: Genes are DNA sequences that contribute to traits.

25. Answer: alleles

How to solve: Alleles are alternative versions of a gene.

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Answer Key — Questions 26–30

Answer + How to Solve

26. Answer: homozygous

How to solve: Homozygous means the two alleles are the same.

27. Answer: possible offspring genotypes

How to solve: It models allele combinations from parents.

28. Answer: help populations adapt

How to solve: Variation gives natural selection different traits to act on.

29. Answer: gene

How to solve: Genes are DNA sequences that contribute to traits.

30. Answer: alleles

How to solve: Alleles are alternative versions of a gene.

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Answer Key — Questions 31–35

Answer + How to Solve

31. Answer: Response should correctly apply: alleles.

How to solve: Define the concept, connect it to the scenario, and cite the observation or measurement that supports the connection. Alleles are alternative versions of a gene.

32. Answer: Response should correctly apply: homozygous.

How to solve: Define the concept, connect it to the scenario, and cite the observation or measurement that supports the connection. Homozygous means the two alleles are the same.

33. Answer: Response should correctly apply: possible offspring genotypes.

How to solve: Define the concept, connect it to the scenario, and cite the observation or measurement that supports the connection. It models allele combinations from parents.

34. Answer: Response should correctly apply: help populations adapt.

How to solve: Define the concept, connect it to the scenario, and cite the observation or measurement that supports the connection. Variation gives natural selection different traits to act on.

35. Answer: Response should correctly apply: gene.

How to solve: Define the concept, connect it to the scenario, and cite the observation or measurement that supports the connection. Genes are DNA sequences that contribute to traits.

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Answer Key — Questions 36–40

Answer + How to Solve

36. Answer: Response should correctly apply: alleles.

How to solve: Define the concept, connect it to the scenario, and cite the observation or measurement that supports the connection. Alleles are alternative versions of a gene.

37. Answer: Response should correctly apply: homozygous.

How to solve: Define the concept, connect it to the scenario, and cite the observation or measurement that supports the connection. Homozygous means the two alleles are the same.

38. Answer: Response should correctly apply: possible offspring genotypes.

How to solve: Define the concept, connect it to the scenario, and cite the observation or measurement that supports the connection. It models allele combinations from parents.

39. Answer: Response should correctly apply: help populations adapt.

How to solve: Define the concept, connect it to the scenario, and cite the observation or measurement that supports the connection. Variation gives natural selection different traits to act on.

40. Answer: Response should correctly apply: gene.

How to solve: Define the concept, connect it to the scenario, and cite the observation or measurement that supports the connection. Genes are DNA sequences that contribute to traits.

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Answer Key — Questions 41–45

Answer + How to Solve

41. Answer: Response should correctly apply: alleles.

How to solve: Define the concept, connect it to the scenario, and cite the observation or measurement that supports the connection. Alleles are alternative versions of a gene.

42. Answer: Response should correctly apply: homozygous.

How to solve: Define the concept, connect it to the scenario, and cite the observation or measurement that supports the connection. Homozygous means the two alleles are the same.

43. Answer: Response should correctly apply: possible offspring genotypes.

How to solve: Define the concept, connect it to the scenario, and cite the observation or measurement that supports the connection. It models allele combinations from parents.

44. Answer: Response should correctly apply: help populations adapt.

How to solve: Define the concept, connect it to the scenario, and cite the observation or measurement that supports the connection. Variation gives natural selection different traits to act on.

45. Answer: Response should correctly apply: gene.

How to solve: Define the concept, connect it to the scenario, and cite the observation or measurement that supports the connection. Genes are DNA sequences that contribute to traits.

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Answer Key — Questions 46–50

Answer + How to Solve

46. Answer: Answers vary; investigation must correctly demonstrate gene.

How to solve: State a testable setup, identify the variable/measurement, predict an observable result, and explain why that result demonstrates the concept.

47. Answer: Answers vary; investigation must correctly demonstrate alleles.

How to solve: State a testable setup, identify the variable/measurement, predict an observable result, and explain why that result demonstrates the concept.

48. Answer: Answers vary; investigation must correctly demonstrate homozygous.

How to solve: State a testable setup, identify the variable/measurement, predict an observable result, and explain why that result demonstrates the concept.

49. Answer: Answers vary; investigation must correctly demonstrate possible offspring genotypes.

How to solve: State a testable setup, identify the variable/measurement, predict an observable result, and explain why that result demonstrates the concept.

50. Answer: Answers vary; investigation must correctly demonstrate help populations adapt.

How to solve: State a testable setup, identify the variable/measurement, predict an observable result, and explain why that result demonstrates the concept.