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Science Concepts
Using Science Graphics
Writing Skills

2. 1. Which of the following sex chromosomes do human females have?
A. XY
B. XX
C. YY
D. XO

3. 1. Which of the following sex chromosomes do human females have?
A. XY
B. XX
C. YY
D. XO

4. 2. If the diploid chromosome number of a species is 24, then a cell with 12 chromosomes would be
F. a zygote.
G. a polyploid cell.
H. a haploid cell.
J. a diploid cell.

5. 2. If the diploid chromosome number of a species is 24, then a cell with 12 chromosomes would be
F. a zygote.
G. a polyploid cell.
H. a haploid cell.
J. a diploid cell.

6. 3. The random distribution of homologous chromosomes during meiosis is called
A. fission.
B. budding.
C. crossing-over.
D. independent assortment.

7. 3. The random distribution of homologous chromosomes during meiosis is called
A. fission.
B. budding.
C. crossing-over.
D. independent assortment.

8. 4. In addition to the genetic variability produced during meiosis, sexual reproduction generates genetic variability as a result of
F. mitosis.
G. spore formation.
H. random fertilization.
J. harsh environments.

9. 4. In addition to the genetic variability produced during meiosis, sexual reproduction generates genetic variability as a result of
F. mitosis.
G. spore formation.
H. random fertilization.
J. harsh environments.

10. 5. Sperm formation produces
A. four diploid cells.
B. four haploid cells.
C. four polar bodies.
D. two haploid cells.

11. 5. Sperm formation produces
A. four diploid cells.
B. four haploid cells.
C. four polar bodies.
D. two haploid cells.

12. 6. In a haploid sexual life cycle, meiosis occurs
F. at any stage in the life cycle.
G. in cells of multicellular individuals.
H. immediately after a zygote is formed.
J. at the time when an individual reaches its mature size.

13. 6. In a haploid sexual life cycle, meiosis occurs
F. at any stage in the life cycle.
G. in cells of multicellular individuals.
H. immediately after a zygote is formed.
J. at the time when an individual reaches its mature size.

14. The graph shows chromosome number for different animals
The graph shows chromosome number for different animals. Use the diagram to answer the following question(s). 7. How many chromosomes are in a frog gametes?
A. 13
B. 20
C. 26
D. 62

15. The graph shows chromosome number for different animals
The graph shows chromosome number for different animals. Use the diagram to answer the following question(s). 7. How many chromosomes are in a frog gametes?
A. 13
B. 20
C. 26
D. 62

16. F. dog G. frog H. corn J. human
The graph shows chromosome number for different animals. Use the diagram to answer the following question(s). 8. Which organism has 10 chromosomes in one of its gametes.
F. dog
G. frog
H. corn
J. human

17. F. dog G. frog H. corn J. human
The graph shows chromosome number for different animals. Use the diagram to answer the following question(s). 8. Which organism has 10 chromosomes in one of its gametes.
F. dog
G. frog
H. corn
J. human

18. D. ABcdE, ABcdE, aBCDE, aBCde
The diagram shows chrossing over of two chromatids. Use the diagram to answer the following question(s). 9. After crossing-over as shown, what would the sequence of genes be for each of the chromatids?
A. ABcdE, ABcde, aBCDE,
aBCDe
B. ABEcd, ABcde, aBCDE,
C. ABcdE, ABcde, aBCDE,
aBCdeE
D. ABcdE, ABcdE, aBCDE, aBCde

19. D. ABcdE, ABcdE, aBCDE, aBCde
The diagram shows chrossing over of two chromatids. Use the diagram to answer the following question(s). 9. After crossing-over as shown, what would the sequence of genes be for each of the chromatids?
A. ABcdE, ABcde, aBCDE,
aBCDe
B. ABEcd, ABcde, aBCDE,
C. ABcdE, ABcde, aBCDE,
aBCdeE
D. ABcdE, ABcdE, aBCDE, aBCde

20. 10. Write a one-page report explaining why meiosis is important in sexual reproduction.

21. 10. Write a one-page report explaining why meiosis is important in sexual reproduction.
Reports should include that meiosis increases genetic variation within a species, giving the population a better chance of surviving changing conditions.