1. Cell Division Mitosis and Meiosis

2. Types of Cell Division 1) Mitosis  occurs in all body cells (somatic cells) in animals, plants, and humans production of 2 identical daughter cells that are diploid production of 2 identical daughter cells that are diploid growth or replacement of body cells. growth or replacement of body cells. asexual reproduction. (offspring and parents are identical) asexual reproduction. (offspring and parents are identical)

3. Types of Cell Division 2) Meiosis  occurs only is sex cells (sperm and egg) production of the 4 non-identical gametes (sex cells) that are haploid production of the 4 non-identical gametes (sex cells) that are haploid Sperm and eggs have half the genetic information Sperm and eggs have half the genetic information sexual reproduction sexual reproduction Discovered looking at dividing germ-line cells Discovered looking at dividing germ-line cells

5. The Cell Cycle 10% time dividing (mitotic phase/meiotic phase) 10% time dividing (mitotic phase/meiotic phase) 90% time interphase (G1, S, G2 phases) 90% time interphase (G1, S, G2 phases)

6. Interphase 1) G1 (gap phase) -manufactures proteins and amino acids needed for both cell processes and cell division, carries out metabolic duties Cell grows Cell grows 2) S phase (synthesis phase) – DNA replicates. -longest stage of the cell cycle

7. 3) G2 (gap phase) increases the rate of protein synthesis and prepares to divide. increases the rate of protein synthesis and prepares to divide. grows larger grows larger Cyclins Cyclins are proteins that help control the cell cycle: Two main types of cyclins: 1) G1 cyclins: 1) G1 cyclins: tell the cell to switch from G1 phase to S-phase 2) MPF- mitosis promoting factors made from cyclins create proteins at this point to initiate/promote cells that are in G2 to move into mitosis. Once mitosis is complete MPF degrades and the cell goes back into G1 phase.

8. Division Mitosis or Meiosis Mitosis or Meiosis cell can divide only about 50 times on average. cell can divide only about 50 times on average. To ensure that the cells in a tissue are healthy, cells will undergo a form of cell suicide called apoptosis. To ensure that the cells in a tissue are healthy, cells will undergo a form of cell suicide called apoptosis. Cell Death Cell Death Cell Death Cell Death

9. Terms Chromatin – complex long threads made of DNA and protein that makes up chromosomes Chromatin – complex long threads made of DNA and protein that makes up chromosomes Uncondensed chromosome – long, thin strands not visible with light microscope Uncondensed chromosome – long, thin strands not visible with light microscope Condensed chromosome – short and visible Condensed chromosome – short and visible To help chromosomes condense, histone protein complexs will help DNA windup into spools of nucleosomes first and then chromosomes next. Topoisomerase II will help prevent DNA to tangle up while winding. To help chromosomes condense, histone protein complexs will help DNA windup into spools of nucleosomes first and then chromosomes next. Topoisomerase II will help prevent DNA to tangle up while winding.

11. Chromosome vs. Chromatid Chromosomes replicate before division to form 2 matched sister chromatids Chromosomes replicate before division to form 2 matched sister chromatids

12. Ploidy Humans have 46 chromosomes (diploid or 2N) Humans have 46 chromosomes (diploid or 2N) Sex gametes have 23 chromosomes (haploid or N Sex gametes have 23 chromosomes (haploid or N Some organisms have polyploidy Some organisms have polyploidy Ex) corn – 4n (tetraploidy) Ex) corn – 4n (tetraploidy)

13. Homologous chromosomes – same size and shape and carry the genes for the same traits, but have different details Humans have 23 homologous chromosomes for a total of 46

14. Gene basic unit of heredity basic unit of heredity sequence of nucleotide bases in DNA. sequence of nucleotide bases in DNA. codes for a specific proteins codes for a specific proteins

15. Autosomes – chromosomes that do not influence biological sex (humans have 22 pairs of these) Autosomes – chromosomes that do not influence biological sex (humans have 22 pairs of these) Sex Chromosomes – X and Y chromosomes that determine biological sex in humans (humans have 1 pair of these, the 23 rd chromosome pair) Sex Chromosomes – X and Y chromosomes that determine biological sex in humans (humans have 1 pair of these, the 23 rd chromosome pair)

16. Mitosis

17. Prophase (longest phase) Early: chromatin condenses to form chromosomes, centrioles move to poles and attach to spindle fibres Early: chromatin condenses to form chromosomes, centrioles move to poles and attach to spindle fibres Late: spindle fibres attach to centromere, nuclear membrane dissolves Late: spindle fibres attach to centromere, nuclear membrane dissolves

18. Metaphase chromosomes line up on the equatorial plate (center of the nucleus) chromosomes line up on the equatorial plate (center of the nucleus)

19. Anaphase Spindle fibres contract from the centrioles and sister chromatids begin to separate apart, immediately chromosomes being to unravel Spindle fibres contract from the centrioles and sister chromatids begin to separate apart, immediately chromosomes being to unravel

20. Telophase nucleolus re-appears, nuclear membrane reforms, the chromosomes unravel to form a loose mass of chromatin nucleolus re-appears, nuclear membrane reforms, the chromosomes unravel to form a loose mass of chromatin cells undergo cytokinesis (divide cytoplasm) cells undergo cytokinesis (divide cytoplasm)

21. Plant vs Animal Cells a cell plate forms between the new daughter cells a cell plate forms between the new daughter cells the cell membrane pinches in between the two daughter cells

22. Mitosis Overall http://www.loci.wisc.edu/outreach/bioclips/CDBio.html http://www.loci.wisc.edu/outreach/bioclips/CDBio.html http://www.loci.wisc.edu/outreach/bioclips/CDBio.html

23. Some Methods of Asexual Reproduction 1. Binary fission - equal division of both the organism cytoplasm and nucleus to form two identical organisms ex: Protist, amoeba ex: Protist, amoeba

24. Budding - one parent dividing its nucleus (genetic material) equally, but cytoplasm unequally ex: Fungi- yeast 2) Budding - one parent dividing its nucleus (genetic material) equally, but cytoplasm unequally ex: Fungi- yeast -This is also known as sporulation in yeast

26. Meiosis – Sexual Cell Division Occurs in sexual reproduction The end result is 4 gamates that are genetically different Spermatagonium  4 sperms Oogonium  4 eggs

27. Meiosis I – Reduction Division Prophase I – homologous chromosomes undergo synapsis (pair up) and crossing over occurs. -also, as in mitosis prophase: Chromos condense Nuclear membrane disappears Centrioles move to opposite poles-tetrad

28. Metaphase I – homologous pairs line up along the equatorial plate, spindles insert into the centromeres. Metaphase I – homologous pairs line up along the equatorial plate, spindles insert into the centromeres.

29. Anaphase I – homologous chromosomes separate and are pulled to opposite poles Anaphase I – homologous chromosomes separate and are pulled to opposite poles = segregation

30. Chromosomes undergo independent assortment in during Anaphase I Chromosomes undergo independent assortment in during Anaphase I -increases genetic diversity

31. Telophase I – daughter cells separate, each has one chromosome from each homologous pair. Telophase I – daughter cells separate, each has one chromosome from each homologous pair. -reduction has occurred so that the new cells will be haploid (n) -cytokinesis occurs -cytokinesis occurs

32. Meiosis II – like mitosis but no initial replication of DNA -very brief, not as long as meiosis I Prophase II –spindles form Prophase II –spindles form

33. Metaphase II –chromosomes align at the equatorial plate Metaphase II –chromosomes align at the equatorial plate

34. Anaphase II – the daughter chromatids separate and move towards separate poles Anaphase II – the daughter chromatids separate and move towards separate poles

35. Telophase II – spindle fibres disappear, nuclei reform and cytokinesis takes place. (All 4 daughter cells are haploid.) Telophase II – spindle fibres disappear, nuclei reform and cytokinesis takes place. (All 4 daughter cells are haploid.)

36. How many genetic combinations of gamates? The number of possible chromosome combination in a gamate is 2^n The number of possible chromosome combination in a gamate is 2^n Where ‘n’ is the haploid number Where ‘n’ is the haploid number Ex. Humans n=23, thus 2^23 =8, 388, 608 different combinations!! Ex. Humans n=23, thus 2^23 =8, 388, 608 different combinations!! Now THAT’S diversity!! Now THAT’S diversity!!

37. NOVA Online | 18 Ways to Make a Baby | How Cells Divide: Mitosis vs. Meiosis (Flash) NOVA Online | 18 Ways to Make a Baby | How Cells Divide: Mitosis vs. Meiosis (Flash) NOVA Online | 18 Ways to Make a Baby | How Cells Divide: Mitosis vs. Meiosis (Flash) NOVA Online | 18 Ways to Make a Baby | How Cells Divide: Mitosis vs. Meiosis (Flash)

38. Human Life Cycle

39. Fern Life Cycle

40. Oogenesis

41. Spermatogenesis

42. Oogenesis vs Spermatogenesis Oogenesis (female) Oogenesis (female) meiosis II completes only if egg is fertilized meiosis II completes only if egg is fertilized Secondary oocyte receives most of the cytoplasm and becomes the egg Secondary oocyte receives most of the cytoplasm and becomes the egg polar bodies have less cytoplasm and degenerate polar bodies have less cytoplasm and degenerate one egg cell is produced one egg cell is produced Spermatogenesis (male) meiosis I and II are both completed before fertilization each sperm cell produced receives an equal share of cytoplasm flagellum forms from one of the centrioles four spermatids are produced

43. Human Karyotype Chart Karyogram: A diagram or photograph of the chromosomes of a cell, arranged in homologous pairs and in a numbered sequence. Karyotype: The characterization of the chromosomal complement of an individual or a species, including number, form, and size of the chromosomes.

44. Biological Sex Female is XX Female is XX Male is XY Male is XY XX XY

46. Chromosomal abnormalities can be detected by doing a karyotype chart. Chromosomal abnormalities can be detected by doing a karyotype chart. Fetal cells are collected through amniocentesis or chorionic villi sampling Fetal cells are collected through amniocentesis or chorionic villi sampling

47. Successful cell division relies on 2 things: 1. accurate replication of the chromosomes (during S-phase of interphase) 2. exact separation / distribution of the chromosomes (usualy during anaphase I of meiosis)

48. Trisomy –three chromosomes replace a normal pair (47 chromosomes in humans) Trisomy –three chromosomes replace a normal pair (47 chromosomes in humans)

49. Abnormal Meiosis Non-disjunction – occurs during meiosis when two homologous chromosomes move to the same pole. Chromosomes do not separate properly Non-disjunction – occurs during meiosis when two homologous chromosomes move to the same pole. Chromosomes do not separate properly Normal DivisionNon-disjunction

50. Some Common Genetic Disorders **Research shows a higher incidence of these disorder in parents over 40 that have children Down’s syndrome – trisomy 21 Extra 21 chromosome Extra 21 chromosome more common in children born to women over 40 more common in children born to women over 40 characterized by short stature, folds to the eyelids, stubby fingers, wide gap between 1st and 3rd toes, large fissured tongue, round head, palm creases, mild to severe mental retardation. characterized by short stature, folds to the eyelids, stubby fingers, wide gap between 1st and 3rd toes, large fissured tongue, round head, palm creases, mild to severe mental retardation.

52. Edward’s syndrome – trisomy 18 results in severe overall defects with a life expectance of only 10 weeks results in severe overall defects with a life expectance of only 10 weeks Patau’s syndrome – trisomy 13 results in non-functioning eyes, severe deficits and limited life expectancy. results in non-functioning eyes, severe deficits and limited life expectancy.

53. Klinefelter’s syndrome – XXY male sterile males with underdeveloped testes, overdeveloped breast tissue and sub-normal intelligence sterile males with underdeveloped testes, overdeveloped breast tissue and sub-normal intelligence

54. Metafemale – XXX female no obvious deficits however menstrual irregularities and early menopause are common, some have increase aggression no obvious deficits however menstrual irregularities and early menopause are common, some have increase aggression XYY male taller than normal, recurrent acne taller than normal, recurrent acne

55. Monosomy –one chromosome replaces a normal pair (45 chromosomes in humans) Monosomy –one chromosome replaces a normal pair (45 chromosomes in humans)

56. Turner’s syndrome – XO female females with short stature, broad chest, heart defects, lack of breasts and absence of sexual maturation and menstruation females with short stature, broad chest, heart defects, lack of breasts and absence of sexual maturation and menstruation Cri du Chat syndrome deletion of a portion of one copy of chromosome number 5, malformed face and head, short life deletion of a portion of one copy of chromosome number 5, malformed face and head, short life

57. Societal Issues of Cell Division Cloning identical offspring are formed from a single cell or tissue of the parent. (similar to mitosis) identical offspring are formed from a single cell or tissue of the parent. (similar to mitosis) when plants send out runners, when bacteria divide and in identical twins. when plants send out runners, when bacteria divide and in identical twins.

59. How to Clone: (the quick and easy, yet not so successful way to carry out somatic-cell nuclear transfer) Take an egg cell from an adult female and remove the nucleus (enucleation). Take an egg cell from an adult female and remove the nucleus (enucleation). Replace the nucleus with the nucleus from a body cell of the individual to be cloned. Replace the nucleus with the nucleus from a body cell of the individual to be cloned. (the cell must be toti-potent, or have its identity genes turned off) (you can use stem cells here)

60. Zap it!!! (a little magic is required here) Zap it!!! (a little magic is required here) Implant the zygote or blastula into the mother’s uterus. Implant the zygote or blastula into the mother’s uterus. Wait until the gestational period is up and voila! Wait until the gestational period is up and voila! Click and Clone Click and Clone Click and Clone Click and Clone

62. Dolly 1997-2003 1997-2003 nucleus from udder cell put into egg cell nucleus from udder cell put into egg cell

63. Problems with cloning: some think it is wrong!!! (ethical issue) some think it is wrong!!! (ethical issue) artificially cloned organisms seem to age faster artificially cloned organisms seem to age faster it is very time and resource consuming and is not guaranteed to work it is very time and resource consuming and is not guaranteed to work

64. Societal Issues Ethical Issues: Issues that deal with right or wrong, beliefs….not always religion vs science Ethical Issues: Issues that deal with right or wrong, beliefs….not always religion vs science Economical: Issues that deal with money, expenses, cost, cost vs benefit/time Economical: Issues that deal with money, expenses, cost, cost vs benefit/time Socio-economical: issues dealing with class differences Socio-economical: issues dealing with class differences Environmental: Issues dealing with changes to the abiotic or biotic aspects of an ecosystem Environmental: Issues dealing with changes to the abiotic or biotic aspects of an ecosystem Government: Issues dealing with bylaws, rules, control Government: Issues dealing with bylaws, rules, control

65. Cell Ageing the ends of the chromosomes, called telomeres, shorten each time a cell divides, and when they become critically short, the cell dies. the ends of the chromosomes, called telomeres, shorten each time a cell divides, and when they become critically short, the cell dies. Totipotent: when cells reach a certain number of divisions, or age, DNA begins to altered

66. Cancer abnormal, uncontrolled cell division. abnormal, uncontrolled cell division. May be caused due to mutation of genes May be caused due to mutation of genes Tumour suppressor genes – suppress cell division. (mutation turns these off) Tumour suppressor genes – suppress cell division. (mutation turns these off) Proto-oncogenes – stimulate cell division. (mutation turns these on) Proto-oncogenes – stimulate cell division. (mutation turns these on) Telomeres do not shrink in cancerous cells Telomeres do not shrink in cancerous cells

67. Cancer cells do not participate in helping the body to function. Cancer cells do not participate in helping the body to function. Cancer cells require and take away nutrients Cancer cells require and take away nutrients Cancer cells can break away (metastasis) from the tumour mass and spread to other parts of the body. Cancer cells can break away (metastasis) from the tumour mass and spread to other parts of the body. NOVA Online | Cancer Warrior | How Cancer Grows NOVA Online | Cancer Warrior | How Cancer Grows NOVA Online | Cancer Warrior | How Cancer Grows NOVA Online | Cancer Warrior | How Cancer Grows Why is cancer bad

68. Pandos + Dolly = Pure Bio Magic #dreamcometrue