Mitosis and meiosis are two types of cell division. Mitosis is the process where one cell divides into two identical daughter cells, maintaining the original chromosome number. It is used for growth, tissue repair, and asexual reproduction. Meiosis involves two cell divisions that result in four haploid cells, each with half the number of chromosomes as the original parent cell. Meiosis occurs in the formation of gametes and allows for genetic diversity through independent assortment and recombination of parental chromosomes.

1. MITOSIS & MEIOSIS + terms exercise

2. Role of Mitosis Formation of a multicellular organism. Asexual reproduction e.g. Amoeba, yeast and vegetative reproduction of plant. Cell replacement and regeneration. Gamete formation in the flowering plant. Faithful copying of genes and their transfer to the next generation of nuclei or cells. Maintains the correct chromosome number of somatic cells.

4. http://highered.mcgraw-hill.com/sites/0073031216/student_view0/exercise13/mitosis_movie.html Movie from mc graw hill about mitosis

5. Can u identify each phase? http://buenconsejoicod.com/wordpress/?p=60 Real microscopic images:

6. PRO MET ANA TELO http://buenconsejoicod.com/wordpress/?p=60 Real microscopic images:

7. ? phase chromatin condenses forming chromosomes each chromosome composed of two identical sister chromatids connected at the centromere spindle fibres forming nuclear membrane breaks down towards the end of prophase Draw the phase Texts from: http://www.skoool.ie/skoool/examcentre_sc.asp?id=2848

8. ? phase chromosomes placed individually along the equatorial plane of the cell each chromosome is connected to both sides of the cell by spindle fibres attached to the centromeres Draw the phase Texts from: http://www.skoool.ie/skoool/examcentre_sc.asp?id=2848

9. ? phase separation of sister chromatids, now termed chromosomes the centromeres spit when the spindle fibres shorten continued shortening results in two identical sets of chromosomes at opposite sides of the cell Draw the phase Texts from: http://www.skoool.ie/skoool/examcentre_sc.asp?id=2848

10. Draw the phase ? phase each chromosome group becomes a nucleus when a membrane is formed around it the chromosomes uncoil to chromatin Texts from: http://www.skoool.ie/skoool/examcentre_sc.asp?id=2848

11. Idnetify the phases Images from http://www.microscope-microscope.org/activities/school/mitosis.htm

12. Chromosome

13. Types of chromosomes

14. Cell Division Mitosis is the process of cell division in which one cell becomes two identical daughter cells. It is required for development renewal regeneration

17. MEIOSIS

18. Meiosis Specialized form of cell division with two successive rounds (MEIOSIS I + MEIOSIS II) of cell division without DNA replication in between . Produces haploid cells (n)

19. Meiosis Start with 46 double stranded chromosomes (2n) After 1st division - 23 double stranded chromosomes (n) After 2nd division - 23 single stranded chromosomes (n) Occurs in our germ cells cells that produce our gametes egg and sperm

20. MEIOSIS = MEIOSIS I + MEIOSIS II Meiosis I : the reduction division Meiosis II : the equational division

21. Meiosis I : the reduction division crossing over . Chromosomes splitting apart (not chromatids)r . Prophase I (early) (diploid) Prophase I (late) (diploid) Metaphase I (diploid) Anaphase I (diploid) Telophase I (diploid) Nucleus Spindle fibers Nuclear envelope

22. Meiosis II : the equational division Prophase II (haploid) Metaphase II (haploid) Anaphase II (haploid) Telophase II (haploid) Four nonidentical haploid daughter cells

23. Results of meiosis Gametes Four haploid cells One copy of each chromosome One allele of each gene Different combinations of alleles for different genes along the chromosome

24. Why do we have meiosis? To generate haploid gametes! To make new combinations of genes. How? Random (independent) assortment Recombination

25. Why do we need meiosis? - to bring two haploid gametes together to form a diploid zygote. n (mom) + n (dad) = 2n (offspring) It is the fundamental basis of sex. What is the purpose of sex ?

26. MEIOSIS Difference between mitosis and meiosis I

27. Why form gametes? Goal: Reduce genetic material by half from mom from dad child meiosis reduces genetic content too much!

30. Make a table with the differences Meioisis vs. Mitosis http:// dobsomnimedia.blogspot.com /

31. Meioisis vs . Mitosis Mitosis Meiosis Number of divisions 1 2 Number of daughter cells 2 4 Genetically identical? Yes No Chromosome # Same as parent Half of parent Where Somatic cells Germline cells When Throughout life At sexual maturity Role Growth and repair Sexual reproduction

32. Class-room exercise GUESS THE 10 WORDS

33. The cell genetically identical to another. 1

34. A network of filaments that collectively form a mitotic spindle (in mitosis ) and meiotic spindle (in meiosis ). It is chiefly involved in moving and segregating the chromosomes during nuclear division. 2

35. The constricted region joining the two sister chromatids that make up an X-shaped chromosome . 3

36. A structure within the cell that bears the genetic material as a threadlike linear strand of DNA bonded to various proteins in the nucleus of eukaryotic cells . 4

37. They are the products of the division of the parent cell. 5

38. A form of cell division happening in sexually reproducing organisms by which two consecutive nuclear divisions occur without the chromosomal replication in between, leading to the production of four haploid gametes ( sex cells ) 6

39. The stage of the cell or nucleus when it is not in mitosis , hence comprising most of the cell cycle . 7

40. The final stage of mitosis, when chromosome separation is completed. 8

41. Body cells are called ................ ............... 9

42. It is the process that our body uses to grow and replace cells. 10

43. ANSWERS

44. Clone The cell genetically identical to another. 1

45. Spindle fibres A network of filaments that collectively form a mitotic spindle (in mitosis ) and meiotic spindle (in meiosis ). It is chiefly involved in moving and segregating the chromosomes during nuclear division. 2

46. Centromere The constricted region joining the two sister chromatids that make up an X-shaped chromosome . 3

47. Chromosome A structure within the cell that bears the genetic material as a threadlike linear strand of DNA bonded to various proteins in the nucleus of eukaryotic cells . 4

48. Daughter cells They are the products of the division of the parent cell. 5

49. Meiosis A form of cell division happening in sexually reproducing organisms by which two consecutive nuclear divisions occur without the chromosomal replication in between, leading to the production of four haploid gametes ( sex cells ) 6

50. Interphase The stage of the cell or nucleus when it is not in mitosis , hence comprising most of the cell cycle . 7

51. Telophase The final stage of mitosis, when chromosome separation is completed. 8

52. Somatic cells Body cells are called ................ ............... 9

53. Mitosis It is the process that our body uses to grow and replace cells. 10

54. http :// www.biology - online.org / dictionary / Some definitions were taken from http://www.goboxy.com/vector_stock/vector-cool-design/

55. http://www.webdesignhot.com/free-vector-graphics/free-vector-colorful-dots-background/ Some graphics were taken from

56. Thanks for your attention http://www.designbyhumans.com