1. A SEXUAL & S EXUAL R EPRODUCTION

2. A SSESS Y OUR L EARNING Due Monday, November 3, 2014 #s 1-8

3. R EPRODUCTION PRODUCES NEW INDIVIDUALS OF A SPECIES. The way a species reproduces determines how much variation the new individuals will have.

4. R EPRODUCTION … Can produce new individuals that are identical to or very different from one another.

5. Which produces greater variation in individual organisms… Asexual or Sexual Reproduction?

6. A SEXUAL R EPRODUCTION Involves only one parent. All offspring that result from asexual reproduction are identical to that parent. In other words, the adult makes an exact copy of itself. There are several different forms of asexual reproduction.

7. 1. B INARY F ISSION

8. B INARY F ISSION Only 1 cell organisms, and some protists, such as amoebas and some algae, reproduce by binary fission. During binary fission, a cell splits exactly in two, producing two identical individuals. Binary = two Fission = splitting or dividing (cleavage)

10. R EMEMBER … The Protista Kingdom consists of unicellular lifeforms (lifeforms with only one cell) who have a nucleus. The primary difference between protists and monera (bacteria) is that protists are more complex, having a nucleus.

11. 2. B UDDING

12. O RGANISMS … Such as hydra and yeast reproduce asexually by budding. During budding, the parent produces a small “bud”, or a smaller version of itself. In most animals (like the hydra) and unicellular fungus (yeast), the bud detaches and becomes a new individual identical to its parent. In some (such as coral) the offspring remains attached to the parent, forming a large structure composed of many identical individuals.

14. S PORE P RODUCTION

15. S PORES Similar to seeds, but are produced by the division of cells of the parent, not by the union of two cells.

16. O NE INDIVIDUAL Will produce many spores, and each spore can develop into a new individual identical to the parent. Most fungi, green algae, some molds, and non- flowering plants, such as ferns, reproduce by producing spores.

17. 4. V EGETATIVE R EPRODUCTION

18. T HERE ARE DIFFERENT FORMS OF V EGETATIVE R EPRODUCTION Vegetative reproduction is the reproduction of a plant that does not involve the formation of a seed. Most plants can reproduce this way.

19. I F YOU TAKE A “ CUTTING ” FROM A PLANT … And place it in water, the cutting will grow roots and eventually develop into a whole new plant.

20. Many plants, such as strawberries or spider plants, grow runners that produce new plants.

21. T UBERS … Such as potatoes on a potato plant, and bulbs, from which tulips develop, are also forms of vegetative reproduction.

22. T HE ROOTS OF AN ASPEN TREE … Form a shoot called a “sucker”; if the sucker becomes separated from the original tree, it will grow into a new aspen tree.

23. I N ALL OF THESE FORMS OF VEGETATIVE REPRODUCTION … The individual new plants that are produced will be genetically identical to their parent plant and to one another.

24. D IAGRAM IT !!! Make a labeled diagram illustrating the kinds of asexual to show how an organism reproduces by that form. Compare your diagrams. Describe any similarities and differences between them. Hand in your work

25. P ARTHENOGENESIS : “Virgin Birth” in Greek. Describes the process that transforms unfertilized eggs into mature organisms. In bees, unfertilized eggs become the male drones, and fertilized eggs become female workers and queens. Has been observed in snakes and plants (figs)

26. S EXUAL R EPRODUCTION

27. S EXUAL R EPRODUCTION … Usually involves 2 individuals. Most animals and flowering plants reproduce sexually.

28. O FFSPRING … Will have a mix of characteristics of both individuals.

29. D OES SEXUAL REPRODUCTION ALWAYS INVOLVE A MALE AND A FEMALE ?

31. S EXUAL R EPRODUCTION IN PLANTS & ANIMALS … Relies on the union of specialized cells known as gametes.

32. M ALE G AMETES : Sperm cells.

33. F EMALE G AMETES : Egg cells (ova)

34. T HE UNION OF THE SPERM AND EGG Happens during mating and is called fertilization.

35. T HE CELL CREATED BY THE JOINING OF … 2 gametes (egg & sperm) is known as a zygote.

36. T HE ZYGOTE Is the first cell of a new individual. The zygote then divides into two cells. The same divisions are repeated during a process called cleavage.

37. C ONTINUED C ELL D IVISION : Results in a new multicellular life form known as an embryo.

38. D EPENDING ON THE SPECIES Development of the embryo may occur inside the female parent, or outside, inside the egg.

39. S EXUAL R EPRODUCTION IN PLANTS Most plants produce both male (sperm) and female (egg) gametes. Some produce only female and only male. Pollen: contains the male gametes; found in the stamen (male part of plant). Ovules: contain the female gametes; found in the pistil (female part of the plant).

40. P OLLINATION OCCURS WHEN POLLEN IS TRANSFERRED FROM THE ANTHER TO THE STIGMA.

41. C ROSS - POLLINATION … Occurs when the pollen of one plant is carried to the stigma of another by wind, water, or animals.

42. C ROSS -F ERTILIZATION Occurs when a grain of this pollen produces a long tube that eventually grows down the style into the ovary that contains the ovules. In most plants, the embryo is produced inside a seed.

43. T HE SEED … Protects the embryo and stores food the the embryo for when it starts to grow into a new individual. Unlike animals, the new embryo may not begin to grow for some time (remain dormant) until it has suitable growing conditions.

44. A SEXUAL R EPRODUCTION Produces lots of individuals very quickly-less energy E.G. Bacteria- every 20 minutes; 12 hrs, 10 million copies of itself Great advantage in environments that don’t change much- warm/moist If conditions change/become unfavourable, the entire population may be wiped out. E.G. Every single one of the 10 million could be wiped out by an anti-biotic. AdvantagesDisadvantages

45. SEXUAL R EPRODUCTION Provides lots of variation which helps a species survive environmental change. Takes a lot of energy and time. Can only produce a limited number of offspring. AdvantagesDisadvantages

46. O RGANISM THAT REPRODUCE SEXUALLY & ASEXUALLY Most plants can. Seeds (sexually) or Cuttings/Bulbs/Runners (asexually) When plants reproduce by asexually, the offspring is genetically identical to the parent.

47. S OME ANIMALS CAN REPRODUCE SEXUALLY & A SEXUALLY : Aphids (small insects); throughout the growing season, females produce live female young without fertilization (asexual reproduction).

48. S OME ANIMALS CAN REPRODUCE SEXUALLY & A SEXUALLY : In the fall, when the temperature drops, the female produces males & females who then reproduce sexually, and lay eggs that will hatch in the spring.

49. S OME ANIMALS CAN REPRODUCE SEXUALLY & A SEXUALLY : Sponges can also reproduce sexually and asexually.

50. S OME ANIMALS CAN REPRODUCE SEXUALLY & A SEXUALLY : Jellyfish alternate between sexual and asexual reproduction.

51. H ERMAPHRODITES Can produce both male and female gametes (common garden worms & slugs). Prefer to mate with other individuals, but in times of environmental stress, can fertilize themselves. In humans, hermaphroditism is an extremely rare sex anomaly. A true hermaphrodite is an individual who has both ovarian and testicular tissue (both reproductive organs).