1. CHAPTER 6 Meiosis is the basis of Sexual Reproduction

2. S ECTION 6.1 PAGE 170 Meiosis

3. SEXUAL REPRODUCTION Form of reproduction which requires two parents, egg and sperm Produces offspring that are genetically different from each other and any other member of the species Can occur in plants and animals

4. MEIOSIS The process that produces gametes `` sex cells `` – egg in female and sperm in male with half the number of chromosomes as body cells.

5. H APLOID VS. D IPLOID Haploid = half the genetic content (n) Diploid = genetic equal to the parent. Full genetic content (2n) HaploidDiploid

7. 46 H UMAN C HROMOSOMES

8. 8 S TAGES OF MEIOSIS P rophase I M etaphase I A naphase I T elophase I P rophase II M etaphase II A naphase II T elophase II MEIOSIS I MEIOSIS II

9. Meiosis

10. MEIOSIS I –R ESULTS IN 2 DAUGHTER CELLS + Telophase I

11. MEIOSIS II –R ESULTS IN 4 H APLOID C ELLS EACH WITH HALF THE NUMBER OF CHROMOSOMES + Telophase II

12. FORMATION OF EGG AND SPERM Only 1 egg survives www.cellsalive.com

13. Question?MitosisMeiosis Where does it take place? How many cells are produced? What happens to the number of Chromosomes? Type of Reproduction?

14. Question?MitosisMeiosis Where does it take place? In Body CellsIn Sex organs How many cells are produced? 2 daughter cells4 daughter cells What happens to the number of Chromosomes? Same Number of Chromosomes as Parent ½ the number of Chromosomes as Parent Type of Reproduction? Asexual Reproduction Sexual Reproduction

15. C ORE L AB A CTIVITY 6-1B PAGE 176-7 “Comparing Mitosis & Meiosis”

16. S ECTION 6.2 PAGE 180 Sexual Reproduction

17. F ERTILIZATION ( THE UNION OF E GG AND S PERM TO CREATE A ZYGOTE ) MAY OCCUR : Outside the bodies of the parents – External Fertilization OR Inside the mothers body where the developing embryo is nourished for a period of time – Internal Fertilization

18. S EXUAL R EPRODUCTION I N : 1. Mosses External fertilization Water allows the egg and sperm cells to meet Has both sexual and asexual stages in its life cycle

19. S EXUAL R EPRODUCTION IN A M OSS P LANT

20. S EXUAL R EPRODUCTION I N : 2. Flowering Plants External fertilization Pollination - Transfer of male gametes in structures called pollen Pollen adheres to the “sticky” female part of the plant and male gametes fertilize the eggs seeds contain the embryo and are usually protected in fruit or cone

21. S EXUAL R EPRODUCTION IN F LOWERING P LANTS Pollen Video Clip

22. S EXUAL R EPRODUCTION I N : 3. Insects In many insects, the male deposits a package of sperm inside the female. Insects often change a great deal between hatching and adulthood - METAMORPHOSIS

23. 2 T YPES OF METAMORPHOSIS METAMORPHOSIS Four 4 stages Egg - Larva-Pupa-Adult The adult and the larva look completely different Ex. Butterfly Three 3 stages Egg - Nymph - Adult The adult and the nymph resemble one another Ex. Grasshopper Complete Metamorphosis Incomplete Metamorphosis

24. C OMPLETE M ETAMORPHOSIS IN A B UTTERFLY Video Clip

25. I NCOMPLETE M ETAMORPHOSIS IN A G RASSHOPPER Video Clip

26. L ARVA AND P UPA STAGES OF A LADY BUG

27. L ARVA AND P UPA S TAGES OF A HOUSEFLY

28. Asexual 1 parent No gametes Lesser Variation in Offspring Less Energy Required Less Parental Care Sexual 2 parents 2 gametes unite to form a zygote Greater Variation in Offspring Greater Energy Required Greater Parental Care

29. S ECTION 6.3 PAGE 196 Human Reproductive System

30. M ALE R EPRODUCTIVE S YSTEM See Text page 196

31. F EMALE R EPRODUCTIVE S YSTEM See Text page 197

32. M AJOR S TAGES OF H UMAN D EVELOPMENT Fertilization First Trimester (weeks 1-12) Second Trimester (weeks 13-24) Third Trimester (weeks 25-38)

33. F ERTILIZATION Occurs in fallopian tube Egg and sperm unite to produce a zygote

34. F IRST T RIMESTER ( WEEKS 1-12) Movement from fallopian tube to uterus occurs Zygote now called an embryo, attaches to the uterine wall Placenta and amniotic sac form Embryo becomes a fetus at about 8 weeks By the end of this trimester all major organs have begun to develop

35. S ECOND T RIMESTER ( WEEKS 13-24) Skeleton forms Nervous system begins to function Mother begins to feel movement Organs continue to develop

36. T HIRD T RIMESTER ( WEEKS 25-38) Rapid increase in size Immune system develops Increased movement

37. V ISIBLE S IGNS OF P REGNANCY Cessation of Menstrual Flow Cravings Widening of the Hips Weight Gain Morning sickness Enlargement of the Breasts

38. S ECTION 6.4 PAGE 204 Studying Genetic Changes

39. I MPORTANT D EVELOPMENTS IN G ENETICS

40. G REGOR M ENDEL Mid-1800s, Austrian priest Experimented with pea plants Concluded traits were tiny units of inheritance received in pairs, one from each parent

41. T RAITS STUDIED BY G REGOR

42. F RANCIS W ATSON AND J AMES C RICK 1953 Described the “double helix” structure of DNA and how it replicates Won a Noble Prize

43. T HE H UMAN G ENOME P ROJECT 1986-2003 Genome : consists of the full set of genetic material that makes up an organism. Scientist around the world collaborated to make a map to identify genes Used to identify genetic diseases

44. A LLDERDICE S YNDROME Identified in an isolated community of Sandy Point where a high incidence of birth defects were noted, believed to be due to a lack of genetic diversity Symptoms included abnormalities resulting in mental and physical challenges Dr. Allderdice of Memorial University determined that it was caused by part of one chromosomes being reversed.

45. D OWN ’ S S YNDROME Frequently occurring chromosome Mutation Individual has an extra 21 st chromosome Generally results in shorter stature, characteristic facial features and may be prone to developing other diseases

46. C YSTIC F IBROSIS Caused by Gene Mutations Results in the build up of mucus on the Lungs

47. G ENETIC E NGINEERING CORE STSE

48. G ENETIC E NGINEERING Biotechnology that deals with manipulation of the genome