1. Pick up a white index card from the stool in the front of the room as well as ABCD cards Also grab your notebooks

2. On your index card How do you think you grow and repair yourself after you cut your finger? (Hint: think about the three parts of cell theory)

3. Cell Reproduction Cell Cycle, Binary Fission, Mitosis & Meiosis

4. The Cell Cycle and How Cells Divide

5. Functions of Cell Division 20 µm 100 µm 200 µm (a)Reproduction. An amoeba, a single-celled eukaryote, is dividing into two cells. Each new cell will be an individual organism (b) Growth and development. This micrograph shows a sand dollar embryo shortly after the fertilized egg divided, forming two cells (c) Tissue renewal. These dividing bone marrow cells (arrow) will give rise to new blood cells (LM).

6. Cell Division An integral part of the cell cycle Results in genetically identical daughter cells Cells duplicate their genetic material –Before they divide, ensuring that each daughter cell receives an exact copy of the genetic material, DNA

7. Which one of these is NOT a reason for cell division that we talked about? A.Reproduction B.Photosynthesis C.Growth and development D.Tissue repair

8. DNA Genetic information - genome Packaged into chromosomes 50 µm Figure 12.3

9. DNA And Chromosomes An average eukaryotic cell has about 1,000 times more DNA then an average prokaryotic cell. The DNA in a eukaryotic cell is organized into several linear chromosomes, whose organization is much more complex than the single, circular DNA molecule in a prokaryotic cell

10. Chromosomes All eukaryotic cells store genetic information in chromosomes. –Most eukaryotes have between 10 and 50 chromosomes in their body cells. –Human cells have 46 chromosomes. –23 nearly-identical pairs

11. Think about the following… Turn to your should partner and talk about these points. Press Pause, Think, & Share 1)What are the functions of cell division? (Hint there are three main functions) 2)Which structures in the nucleus stores genetic information? 3)How many chromosomes does a human have in their normal body cells?

12. What did you discuss? 1)What are the functions of cell division? (Hint there are three main functions) –Reproduction in some organisms (unicellular) –Growth –Repair 2)Which structures in the nucleus stores genetic information? –Chromosomes 3)How many chromosomes does a human have in their normal body cells? –46 (23 pairs) What are the reactants and products for

13. Time to Write On top of the Cell Cycle Diagram write in the function of cell division Fill in the number or chromosome as well

14. Phases of the Cell Cycle The cell cycle consists of –Interphase – normal cell activity –The mitotic phase – cell division –Cytokinesis INTERPHASE Growth G 1 (DNA synthesis) Growth G 2 Cell Divsion

15. Phases of the Cell Cycle Interphase –G 1 - primary growth –S - genome replicated –G 2 - secondary growth M - mitosis C - cytokinesis

16. Interphase G 1 - Cells undergo majority of growth S - Each chromosome replicates (Synthesizes) to produce sister chromatids –Attached at centromere –Contains attachment site (kinetochore) G 2 - Chromosomes condense - Assemble machinery for division such as centrioles

17. Which represents the correct sequence of stages in the cell cycle? A)G1, G2, S, M B)G1, G2, M, S C)G1, M, G2, S D)G1, S, G2, M E)G1, M, S, G2

18. Chromosomes are duplicated during ____ of the cell cycle. A. G1 phase B. G2 phase C. S phase D. metaphase

19. Mitosis  Eukaryotic cells divide by mitosis  Each new cell receives one copy of every chromosome that was present in the original cell.  Produces 2 new cells that are both genetically identical to the original cell. DNA duplication during interphase Mitosis Diploid Cell

20. Cytokinesis occurs within the nucleus Cleavage of cell into two halves Final Stage of Cell Cycle – within the nucleus

21. The method by which a cell's cytoplasm divides is called ____. A.DNA replication B.interphase C.mitosis D.cytokinesis

22. Think about the following… Turn to your shoulder partner and talk about these points. Press Pause, Think, & Share 1)What are the steps of the cell cycle? (Hint: there are three) 2)Describe the major event that happens in each step.

23. What did you discuss? 1)What are the steps of the cell cycle? (Hint: there are three) –Interphase –Mitosis –Cytokinesis 2)Describe the major even that happens in each step. –Interphase= DNA replicates during the S phase of interphase –Mitosis= Nucleus divides –Cytokinesis= cleavage of cell into two halves What are the reactants and products for

24. Time to Write Using the graphic note guide fill in the information about the stages of the cell cycle and the major events that happen in each stage. When you are finished compare yours to your partners. Made any necessary changes.

25. Binary Fission Most cells reproduce through some sort of Cell DivisionMost cells reproduce through some sort of Cell Division Prokaryotic cells divide through a simple form of division called Binary FissionProkaryotic cells divide through a simple form of division called Binary Fission 3 step process3 step process Single “naked” strand splits and forms a duplicate of itself.Single “naked” strand splits and forms a duplicate of itself. The two copies move to opposite sides of the cellThe two copies move to opposite sides of the cell Cell “pinches” into two new and identical cells called "daughter cells". (Cell wall then forms if applicable)Cell “pinches” into two new and identical cells called "daughter cells". (Cell wall then forms if applicable)

26. You need ABCD cards and your notes packet Make sure your notebook’s cell cycle chart is labeled Make sure your cell cycle questions from yesterday’s reading have been completed BTW: Quiz Tomorrow!

27. Mitosis The process by which eukaryotic cells reproduce themselves, resulting in daughter cells that contain the same amount of genetic material as the parent cell. Occur in body cells (somatic cells)

28. Cell Division Occurs in a series of stages of phases

29. Animated Mitosis Cycle http://www.cellsalive.com/mitosis.htm Prophase Metaphase Anaphase Telophase

30. Interphase occurs before mitosis begins Chromosomes are copied (# doubles) Chromosomes appear as threadlike coils (chromatin) at the start, but each chromosome and its copy(sister chromosome) change to sister chromatids at end of this phase CELL MEMBRANE Nucleus Cytoplasm

31. Why is it necessary for DNA to replicate prior to cell division? A.So that each daughter cell will have 23 chromosomes B.So that each daughter cell will have a complete copy of the genetic material C.So that each daughter cell will have 46 homologous (pairs) of chromosomes D.So that each daughter cell will have 2 sister chromatids

32. The term used for DNA in a nucleus BEFORE it becomes condensed in preparation for mitosis is A) chromosome. B) chromatin. C) cytokinesis. D) centromere.

33. Interphase Animal Cell Plant Cell Photographs from: http://www.bioweb.uncc.edu/biol1110/Stages.htm

34. Prophase 1 st step in Mitosis Nuclear envelope disappears Centrioles appear and begin to move to opposite end of the cell. Spindle fibers form between the poles. Centrioles Sister chromatids Spindle fibers

35. Why do chromosomes have a X-shape? A.Because they are made of two sister chromatins B.Because they are made of sister centromeres C.Because they are made of two sister chromosomes D.Because they are made of two sister chromatids

36. Prophase Animal Cell Plant Cell Photographs from: http://www.bioweb.uncc.edu/biol1110/Stages.htm Spindle fibers Centrioles

37. Metaphase 2 nd step in Mitosis Chromatids (or pairs of chromosomes) attach to the spindle fibers. Line up in the middle of the cell Centrioles Spindle fibers

38. Metaphase Animal Cell Plant Cell Photographs from: http://www.bioweb.uncc.edu/biol1110/Stages.htm

39. Turn to your partner and answer: Partner with the longest hair: –What are the first two stages of mitosis Partner with the shortest hair: –What happens during these two stages

40. Anaphase 3 rd step in Mitosis Chromatids (or pairs of chromosomes) separate and begin to move to opposite ends of the cell. Centrioles Spindle fibers

41. Anaphase Animal Cell Plant Cell Photographs from: http://www.bioweb.uncc.edu/biol1110/Stages.htm

42. Telophase 4th s tep in Mitosis Two new nuclei form. Chromosomes appear as chromatin (threads rather than rods). Mitosis ends. Nuclei Chromatin

43. Telophase Animal Cell Plant Cell Photographs from: http://www.bioweb.uncc.edu/biol1110/Stages.htm

44. Cytokinesis occurs after mitosis Cell membrane moves inward to create two daughter cells – each with its own nucleus with identical chromosomes.

45. 45 Cell Cycle

46. REMEMBER! I Interphase P Prophase M Metaphase A Anaphase T Telophase C Cytokinesis IPMATC I Pray M ore At T he Church

47. Think about the following… Turn to your should partner and talk about these points. Press Pause, Think, & Share 1)What are the phases of mitosis (hint: there are 4) 2)Describe the major even that happens in each phase.

48. What did you discuss? 1)What are the phases of mitosis? (Hint: there are four) –Prophase –Metaphase –Anaphase –Telophase 2)Describe the major even that happens in each step. –Prophase= spindle fibers form, nuclear envelope disappears –Metaphase= chromatide line up at center of cell –Anaphase= chromatide are pulled to opposite ends of the cell –Telophase= nuclei appear, mitosis ends What are the reactants and products for

49. Time to Write Use the guided notes to fill in the information that was just discussed. Once you are finished share your paper with a partner. Make any necessary changes.

50. You need ABCD cards! You need your notes out

51. Meiosis Similar in many ways to mitosisSimilar in many ways to mitosis Several differencesSeveral differences Involves 2 cell divisionsInvolves 2 cell divisions Results in 4 cells with 1/2 the normal genetic informationResults in 4 cells with 1/2 the normal genetic information

52. Vocabulary Diploid (2N) - Normal amount of genetic materialDiploid (2N) - Normal amount of genetic material Haploid (N) - 1/2 the genetic material.Haploid (N) - 1/2 the genetic material. Meiosis results in the formation of haploid cells.Meiosis results in the formation of haploid cells. In Humans, these are the Ova (egg) and sperm.In Humans, these are the Ova (egg) and sperm. Ova are produced in the ovaries in femalesOva are produced in the ovaries in females Process is called oogenesisProcess is called oogenesis Sperm are produced in the testes of males.Sperm are produced in the testes of males. Process is called spermatogenesisProcess is called spermatogenesis

53. Meiosis Phases Meiosis occurs in 2 phases; Meiosis I, & Meiosis II. Meiosis I. –Prior to division, amount of DNA doubles

54. Crossing Over During metaphase 1 homologous chromosomes line-up along the metaphase plateDuring metaphase 1 homologous chromosomes line-up along the metaphase plate Areas of homologous chromosomes connect at areas called chiasmataAreas of homologous chromosomes connect at areas called chiasmata

55. Crossing over contd. Crossing Over of genes occurs nowCrossing Over of genes occurs now –Segments of homologous chromosomes break and reform at similar locations. –Results in new genetic combinations of offspring. –This is the main advantage of sexual reproduction

56. What process does this show? A.protein synthesis B.replication of DNA C.chromosomal segment exchange D.mitosis

57. Chromosome reduction During anaphase 1, each homologous chromosome is pulled to opposite sides of the cell. Unlike mitosis, THE CENTROMERES DO NOT BREAK.During anaphase 1, each homologous chromosome is pulled to opposite sides of the cell. Unlike mitosis, THE CENTROMERES DO NOT BREAK.

58. Think-pair-share Discuss with your table partner: –What does meiosis produce? –What is crossing over? –How is this an advantage?

59. Meiosis I continued Nuclei may or may not reform following division.Nuclei may or may not reform following division. Cytokenesis may or may not occurCytokenesis may or may not occur

60. Meiosis II DNA does not double Chromosomes randomly line-up along metaphase plate like regular mitosis. During anaphase 2, CENTROMERES BREAK and each chromosome is pulled to opposite sides of the cell. Nuclei reform and cytokenesis usually occurs (although it is often unequal).

61. Overview of Meiosis

62. Comparison of Mitosis & Meiosis

63. Meiosis produces ____ in gametes. A.enzymes B.identical daughter cells C.forty-six chromosomes D.genetic variation

64. Try the fluency builder again Don’t forget to keep score AND DON’T LOSE THE PIECES!!!!