1. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu To View the presentation as a slideshow with effects select “View” on the menu bar and click on “Slide Show.” To advance through the presentation, click the right-arrow key or the space bar. From the resources slide, click on any resource to see a presentation for that resource. From the Chapter menu screen click on any lesson to go directly to that lesson’s presentation. You may exit the slide show at any time by pressing the Esc key. How to Use This Presentation

2. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter Presentation Transparencies Standardized Test Prep Visual Concepts Resources

3. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Cell Reproduction Chapter 8 Table of Contents Section 1 Chromosomes Section 2 Cell Division Section 3 Meiosis

4. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Chromosomes Chapter 8 Objectives Describe the structure of a chromosome. Identify the differences in structure between prokaryotic chromosomes and eukaryotic chromosomes. Compare the numbers of chromosomes in different species. Explain the differences between sex chromosomes and autosomes. Distinguish between diploid and haploid cells.

5. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Chromosomes Chapter 8 Chromosome Structure Chromosomes are rod-shaped structures made of DNA and protein. In eukaryotes, DNA wraps around proteins called histones to help maintain the compact structure of chromosomes.

6. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 8 Chromosome Structure Section 1 Chromosomes

7. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 8 Click below to watch the Visual Concept. Visual Concept Parts of a Chromosome Section 1 Chromosomes

8. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Chromosomes Chapter 8 Chromosome Structure, continued Chromosomes in prokaryotes are simpler in structure than chromosomes in eukaryotes.

9. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 8 Comparing Cell Division in Prokaryotes and Eukaryotes Section 1 Chromosomes

10. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Chromosomes Chapter 8 Chromosome Numbers Each species has a characteristic number of chromosomes in each cell.

11. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 8 Chromosome Numbers of Various Organisms Section 1 Chromosomes

12. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Chromosomes Chapter 8 Chromosome Numbers, continued Sex Chromosomes and Autosomes –Sex chromosomes are chromosomes that determine the sex of an organism. –All of the other chromosomes in an organism are autosomes.

13. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 8 Click below to watch the Visual Concept. Visual Concept Sex Chromosomes and Autosomes Section 1 Chromosomes

14. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Chromosomes Chapter 8 Chromosome Numbers, continued Diploid and Haploid Cells –Cells having two sets of chromosomes are diploid (2n). –Haploid cells (1n) have only one set of chromosomes.

15. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 8 Click below to watch the Visual Concept. Visual Concept Karyotype Section 1 Chromosomes

16. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Cell Division Chapter 8 Objectives Describe the events of cell division in prokaryotes. Name the two parts of the cell that are equally divided during cell division in eukaryotes. Summarize the events of interphase. Describe the stages of mitosis. Compare cytokinesis in animal cells with cytokinesis in plant cells. Explain how cell division is controlled.

17. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Cell Division Chapter 8 Cell Division in Prokaryotes Cell division is the process by which cells reproduce themselves.

18. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Cell Division Chapter 8 Cell Division in Prokaryotes, continued Binary fission is the process of cell division in prokaryotes.

19. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Cell Division Chapter 8 Cell Division in Eukaryotes Cell Cycle –The cell cycle is the repeating set of events in the life of a cell. –The cell cycle consists of cell division and interphase. –Cell division in eukaryotes includes nuclear division, called mitosis, and the division of cytoplasm, called cytokinesis.

20. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 8 Cell Cycle Introduction Section 2 Cell Division

21. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Cell Division Chapter 8 Cell Division in Eukaryotes, continued Interphase –Interphase consists of growth (G 1 ), DNA replication, and preparation for cell division (G 2 ).

22. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Cell Division Chapter 8 Stages of Mitosis Mitosis is divided into stages: prophase, metaphase, anaphase, and telophase. Mitosis results in two offspring cells that are genetically identical to the original cell.

23. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 8 Stages of Mitosis Section 2 Cell Division

24. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 8 Mitosis Section 2 Cell Division

25. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Cell Division Chapter 8 Cytokinesis During cytokinesis in animal cells, a cleavage furrow pinches in and eventually separates the dividing cell into two cells. In plant cells, a cell plate separates the dividing cell into two cells.

26. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 8 Click below to watch the Visual Concept. Visual Concept Comparing Cell Division in Plants and Animals Section 2 Cell Division

27. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Cell Division Chapter 8 Control of Cell Division Cell division in eukaryotes is controlled by many proteins. Control occurs at three main checkpoints.

28. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 8 Click below to watch the Visual Concept. Visual Concept Control of the Cell Cycle Section 2 Cell Division

29. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Cell Division Chapter 8 Control of Cell Division, continued When Control is Lost: Cancer –Cancer may result if cells do not respond to control mechanisms.

30. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 3 Meiosis Chapter 8 Objectives Compare the end products of meiosis with those of mitosis. Summarize the events of meiosis I. Explain crossing-over and how it contributes to the production of unique individuals. Summarize the events of meiosis II. Compare spermatogenesis and oogenesis. Define sexual reproduction.

31. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 3 Meiosis Chapter 8 Formation of Haploid Cells Meiosis is a process of nuclear division that reduces the number of chromosomes in new cells to half the number in the original cell. Meiosis produces haploid gametes.

32. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 3 Meiosis Chapter 8 Formation of Haploid Cells, continued Meiosis is a process of nuclear division that reduces the number of chromosomes in new cells to half the number in the original cell. Meiosis leads to four haploid cells (gametes) rather than two diploid cells as in mitosis.

33. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 3 Meiosis Chapter 8 Meiosis I Meiosis I includes prophase I, metaphase I, anaphase I, and telophase I. Crossing-over, which is when portions of homologous chromosomes exchange genetics material, occurs during prophase I and results in genetic recombination.

34. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 8 Click below to watch the Visual Concept. Visual Concept Tetrads and Crossing-over of Genetic Material Section 3 Meiosis

35. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 3 Meiosis Chapter 8 Meiosis II Meiosis II includes prophase II, metaphase II, anaphase II, and telophase II. Four new haploid cells result.

36. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 8 Section 3 Meiosis Stages of Meiosis

37. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 8 Stages of Meiosis, continued Section 3 Meiosis

38. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 8 Click below to watch the Visual Concept. Visual Concept Comparing Meiosis and Mitosis Section 3 Meiosis

39. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 3 Meiosis Chapter 8 Development of Gametes Spermatogenesis is the process by which sperm cells are produced. Oogenesis is the process that produces mature egg cells.

40. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 8 Meiosis in Male and Female Animals Section 3 Meiosis

41. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 3 Meiosis Chapter 8 Sexual Reproduction Sexual reproduction is the formation of offspring through meiosis and the union of a sperm and an egg. Offspring produced by sexual reproduction are genetically different from the parents.

42. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 8 Click below to watch the Visual Concept. Visual Concept Sexual Reproduction Section 3 Meiosis

43. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Multiple Choice 1. Which of the following statements about prokaryotic chromosomes is true? A. Prokaryotes have at least two chromosomes. B. Prokaryotic chromosomes consist of a circular DNA molecule. C. Prokaryotic chromosomes include histone and nonhistone proteins. D. Prokaryotic chromosomes are made of DNA wrapped tightly around histone proteins. Standardized Test Prep Chapter 8

44. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Multiple Choice, continued 1. Which of the following statements about prokaryotic chromosomes is true? A. Prokaryotes have at least two chromosomes. B. Prokaryotic chromosomes consist of a circular DNA molecule. C. Prokaryotic chromosomes include histone and nonhistone proteins. D. Prokaryotic chromosomes are made of DNA wrapped tightly around histone proteins. Standardized Test Prep Chapter 8

45. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Multiple Choice, continued 2. Crossing-over occurs during which process? F. mitosis G. meiosis I H. meiosis II J. interphase Standardized Test Prep Chapter 8

46. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Multiple Choice, continued 2. Crossing-over occurs during which process? F. mitosis G. meiosis I H. meiosis II J. interphase Standardized Test Prep Chapter 8

47. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Multiple Choice, continued 3. In which phase of mitosis do chromatids separate and become individual chromosomes? A. prophase B. metaphase C. anaphase D. telophase/cytokinesis Chapter 8 Standardized Test Prep The graph below shows the relative mass of DNA and chromosome number for a cell undergoing mitosis. Use the graph to answer the questions that follow.

48. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Multiple Choice, continued 3. In which phase of mitosis do chromatids separate and become individual chromosomes? A. prophase B. metaphase C. anaphase D. telophase/cytokinesis Chapter 8 Standardized Test Prep The graph below shows the relative mass of DNA and chromosome number for a cell undergoing mitosis. Use the graph to answer the questions that follow.

49. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Multiple Choice, continued 4. What process occurs that leads to the decrease in the cell’s DNA mass? F. prophase G. metaphase H. anaphase J. telophase/cytokinesis Chapter 8 Standardized Test Prep The graph below shows the relative mass of DNA and chromosome number for a cell undergoing mitosis. Use the graph to answer the questions that follow.

50. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Multiple Choice, continued 4. What process occurs that leads to the decrease in the cell’s DNA mass? F. prophase G. metaphase H. anaphase J. telophase/cytokinesis Chapter 8 Standardized Test Prep The graph below shows the relative mass of DNA and chromosome number for a cell undergoing mitosis. Use the graph to answer the questions that follow.

51. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Multiple Choice, continued 5. prokaryote : binary fission :: eukaryote : A. mitosis B. cytokinesis C. crossing-over D. genetic recombination Chapter 8 Standardized Test Prep

52. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Multiple Choice, continued 5. prokaryote : binary fission :: eukaryote : A. mitosis B. cytokinesis C. crossing-over D. genetic recombination Chapter 8 Standardized Test Prep

53. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Multiple Choice, continued 6. Which type of cell division is shown in the diagram? F. mitosis G. meiosis H. binary fission J. sexual reproduction Chapter 8 Standardized Test Prep The diagram below shows a model of cell division. Use the diagram to answer the question that follows.

54. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Multiple Choice, continued 6. Which type of cell division is shown in the diagram? F. mitosis G. meiosis H. binary fission J. sexual reproduction Chapter 8 Standardized Test Prep The diagram below shows a model of cell division. Use the diagram to answer the question that follows.

55. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Short Response Human cells are either diploid or haploid. All human cells with 46 chromosomes are diploid. Would a human cell with any 23 chromosomes be haploid? Explain your answer. Chapter 8 Standardized Test Prep

56. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Short Response, continued Human cells are either diploid or haploid. All human cells with 46 chromosomes are diploid. Would a human cell with any 23 chromosomes be haploid? Explain your answer. Answer: No, a haploid cell has one complete set of chromosomes, which in the case of humans is 23. Randomly having 23 chromosomes would not be considered haploid. Chapter 8 Standardized Test Prep

57. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Extended Response For a cell to function efficiently, its surface area must exceed that of its volume. Part A Explain how cell division maintains the relationship between surface area and volume. Part B How does a stable ratio between surface area and volume help maintain proper cell functioning? Chapter 8 Standardized Test Prep

58. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Extended Response, continued Answer: Part A The smaller the cell, the greater is the ratio of surface area to volume. Cell division makes one larger cell into two smaller cells. Part B By having a stable ratio between surface area and volume, cells are able to maintain homeostasis by taking in and getting rid of substances efficiently through osmosis and diffusion. Chapter 8 Standardized Test Prep

59. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Cell Division Chapter 8 Cell Division in Prokaryotes