Worksheet Chapter 12: Variation

1. Describe nondisjunction during meiosis and state its effect on gamete chromosome numbers.

2. True or False: Sickle cell anemia is caused by a chromosomal structural mutation.

3. Fill in the blank: Variations that display distinct, non-measurable phenotypic categories without intermediate forms are classified as ________ variation.

4. Explain how crossing over during meiosis contributes to genetic variation among offspring.

5. Define gene mutation and give two examples of human disorders resulting from gene mutations.

6. Which disorder is an example of a chromosomal mutation caused by nondisjunction?

7. A study measured the height of 100 students in a school. Explain why height exhibits continuous variation by referencing genetic and environmental factors.

8. State two differences between continuous variation and discontinuous variation.

9. True or False: Phenotypic changes caused purely by environmental factors can be passed down genetically to offspring.

10. Compare Down syndrome and Turner syndrome in terms of cause, total chromosome number, and sex chromosome constitution.