2. CHAPTER 10 CELL GROWTH AND REGULATION AND ASEXUAL REPRODUCTION

3. KEY CONCEPT QUESTIONS: What are the main events of the cell cycle? What happens during the four phases of mitosis? What factor can stop cells from growing? How is the cell cycle regulated? How are cancer cells different from other cells What are the methods of asexual reproduction?

5. Biology is the only subject in which multiplication is the same thing as division…

6. How do little elephants grow up to be BIG elephants?

7. Why do animals shed their skin?

8. Where it all began… You started as a cell smaller than a period at the end of a sentence…

9. And now look at you… How did you get from there to here?

10. In animals the process of ________ reproduction (mitosis) begins after a sperm fertilizes an egg.

11. Getting from there to here… Function of cell division –making new _____ –continuity of life asexual reproduction –________ organisms growth repair & renew _____ ______ –life of a cell from origin to division into 2 new daughter cells

12. The process by which a cell divides into _____ new daughter cells Before it becomes too ______, a growing cell divides into two daughter cells. CELL DIVISION aka ________ aka ASEXUAL REPRODUCTION

13. Getting the right stuff What is passed on to daughter cells? –exact copy of genetic material = ____ Every living organism has ____, which make up _________________. Each living organism has a certain number of chromosomes –fruit fly = 8 –carrot cells = 18 –human cells = 46 chromosomes (stained orange) in kangaroo rat epithelial cell  notice cytoskeleton fibers

14. ONE CHROMOSOME ONE COPIED CHROMOSOME ________ Chromatid – each side of a replicated chromosome

15. Chromosome Duplicated chromosome consists of 2 ________ _____________ –narrow at their centromeres –contain identical copies of the chromosome’s DNA

16. BIOLOGY JOKE Q: How do you tell the sex of a chromosome? A: Pull down its genes.

17. SAME DNA - JUST LOOKS DIFFERENT CHROMATIN –___________ chromosomes; not visible CHROMOSOMES –_________ up DNA; visible

18. CELL CYCLE ______ of cell life cycle cell doing its “everyday job”

19. Chromosomes are ________ (# doubles) Chromosomes appear as threadlike coils (__________) at the start, but each chromosome and its copy (________ chromosome) change to sister chromatids at end of this phase CELL MEMBRANE NUCLEUS CYTOPLASM INTERPHASE OCCURS BEFORE MITOSIS BEGINS

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

21. INTERPHASE Divided into 3 phases: –G 1 = 1 st Gap cell doing its “everyday job” cell _______ –S = DNA Synthesis ____________ chromosomes –G 2 = 2 nd Gap _________ for division cell grows produces organelles, proteins, membranes

23. MITOSIS Dividing cell’s DNA between 2 daughter nuclei –“dance of the chromosomes” 4 phases –__________ http://www.cellsalive.com/mitosis.htm

24. PROPHASE chromosomes ________ __________ separate –plant cells do not have centrioles __________ disappears ________ ___________ breaks down chromosomes become attached to fibers called _______ ________ at their _______________ CENTRIOLES

25. –Two tiny structures located in the cytoplasm near the ________ ____________, separate and take up positions on ___________ sides of the ___________. –_________ ________ form from them. SPINDLE –A fanlike ___________ structure that helps separate the chromosomes. –Attach from __________ to _____________.

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

27. Metaphase Chromosomes align along _________ of cell –metaphase _______ meta = middle –spindle fibers coordinate movement –helps to ensure chromosomes separate properly so each new nucleus receives only __ copy of each chromosome

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

29. ANAPHASE ___________ separate and _____________ are pulled apart. Spindle reels in the daughter chromosomes to either end of the cell.

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

31. TELOPHASE Chromosomes arrive at opposite poles –___________ ________ form –nucleoli form –chromosomes _________ no longer visible under light microscope Spindle fibers disperse ______________ begins –cell division

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

34. CYTOKINESIS The division of the ___________ In animal cells – cell membrane ________ in until two cells are formed In plant cells – _____ _______ forms midway between the two nuclei – the cell wall gradually appears

36. ONION ROOT TIP

37. MITOSIS IN ANIMAL CELLS

38. REMEMBER! I Interphase P Prophase M Metaphase A Anaphase T Telophase C Cytokinesis IPMATC

39. Coordination of cell division A multicellular organism needs to coordinate cell division across different tissues & organs –critical for normal ________, development & maintenance coordinate timing of cell division coordinate rates of cell division not all cells can have the same _____ _______

40. G2G2 S G1G1 M metaphase prophase anaphase telophase interphase (G 1, S, G 2 phases) mitosis (M) cytokinesis (C) C Frequency of cell division varies by cell type –embryo cell cycle < 20 minute –skin cells divide frequently throughout life 12-24 hours cycle –liver cells retain ability to divide, but keep it in reserve divide once every year or two –mature nerve cells & muscle cells do not divide at all after maturity permanently in G 0 Frequency of cell division

41. How do cells know when to divide? –cell communication _______ chemical signals in cytoplasm give cue signals usually mean _________ –activators –inhibitors Activation of cell division

42. “Go-ahead” signals Protein signals that promote cell growth & division –internal signals “_________ factors” –external signals “_________ factors”

43. How is the cell cycle regulated? –________ regulate the timing of the cell cycle CYCLINS –A protein that seems to __________ the timing of the cell cycle

44. Cancer & Cell Growth Cancer is essentially a failure of cell division _________ –unrestrained, uncontrolled cell growth

45. Mutations in cells can be triggered by –____________ –chemical exposure –radiation exposure –heat –____________ ______ –pollution –age –_________

46. TUMORS Mass of abnormal cells –_______ tumor abnormal cells remain at original site as a lump most do not cause serious problems & can be removed by surgery –____________ tumors cells leave original site –start more tumors = _____________ impair functions of organs throughout body

47. Traditional treatments for cancers Treatments target rapidly dividing cells –high-energy _____________ kills rapidly dividing cells –______________________ stop DNA replication stop mitosis & cytokinesis stop blood vessel growth _________ removal of the tumor –remove the mass and some of the surrounding tissue

48. Methods of Asexual Reproduction ________ ________: equal division of the cytoplasm and nucleus of an organism resulting in two mew organisms –exs. ameba, paramecium, euglena ___________: nucleus of an organism's cell divides equally but the cytoplasm divides unequally –the new cells formed may live as individuals or as colonies exs. yeast, hydra YEAST BUDDING

49. ___________: the production of spores –ex. molds –spores: single, specialized cells which are released from the parent –they are enclosed in a protective case and develop when environmental conditions are favorable

50. _____________: the development of an entire new organism from part of an original organism –ex. starfish -- one ray and part of central body –may also involve the restoration of lost body parts

51. _________ ____________: regeneration in plants –Complete new plants develop from part of the original plant.

52. KEY CONCEPT QUESTIONS: What are the main events of the cell cycle? –____________________________ ____________________________ What happens during the four phases of mitosis? –____________ ___________________________

53. KEY CONCEPT QUESTIONS –_____________ __________________________ –_____________ __________________________ –_____________ __________________________

54. KEY CONCEPT QUESTIONS How is the cell cycle regulated? –________________________ How are cancer cells different from other cells? –________________________ ________________________

55. KEY CONCEPT QUESTIONS What are some methods of asexual reproduction? –____________________