Cell Growth and Division: The Cell Cycle, Mitosis, and Cancer

1. Unit 2: Cells Chapter 5: Cell Growth and Division

2. UNIT 2: Cells Chapter 4: Cell Growth and Division I. The Cell Cycle has four main stages (5.1) A. The _____ ______is a regular pattern of ______, _____________, and ___ ________ in ___________ cells

3. 1. Originally divided into two stages (observations were limited by microscopes at the time) a. __________- cell appeared to be at rest b. ________- cell dividing 2. Improved techniques and tools later allowed scientist to identify 4 distinct stages

4. a. Gap 1 (G1) - cell carries out normal functions 1). ______ increases in ______ 2). _________ increase in numbers

5. b. ___________ (S) - Cell makes copy of its nuclear ______. 1). __________ means “the combining of parts to make a whole. 2). By end of S stage, cell nucleus contains _____complete sets of ______

6. c. Gap 2 (G2) - Cells continue to carry out normal functions 1).Additional _______ occurs 2). Critical ________ (before cell goes through mitosis cell must be adequate size, undamaged DNA)

7. d. _________ (M) - Includes two processes 1). Mitosis - _________ of cell ________ and its contents 2). __________ - Process that ________ the cell __________. Two identical daughter cells produced

8. B. Cells divide at different rates 1. Rates of cell division vary widely a. ____________ cells typically divide much faster than____________cells b. Rate at which cells divide linked to body’s _______ for those cells.

9. 2. In human cells, S, G2, and M stages together usually take about ____________ a. Length of G1 stage differs most for different cell types b. Rate of cell division greater in _________ and _________

10. C. Cell size is limited 1. Cells have upper and lower size limits a. Must be ______ enough to “hold” everything b. Upper limit due to ratio of cell ___________to _________

11. 1).Oxygen, nutrients, and wastes move across the __________________(surface of cell) 2). As cell grows, its surface area (cell membrane) does not grow as fast as volume- too small for adequate ____________________

12. 2. To maintain suitable cell size, growth and cell division must be ____________.

13. II. Mitosis and Cytokinesis (5.2) A. Chromosomes condense at start of mitosis 1. _____________ - one long continuous thread of _______ a. Consists of numerous ________ b. You have ____ chromosomes

14. c. Must be ___________ to fit into cell nucleus 1). ____ wraps around proteins called _______ 2). When loosely condensed called _________

15. d. Chromosome looks like “___” (each half is identical DNA- called a __________) e. ______chromatids held together by _________

16. f. ________ - found at ends of DNA molecules and prevent DNA from coming apart

17. B. Mitosis and cytokinesis producetwo genetically ________ daughter cells 1. ________ - important role in preparing cell to divide (2 sets of _____ and are ______ enough) 2. Mitosis - divides cell’s ________ into two genetically ________ nuclei, each with its own single, full set of _______ Two genetically identical nuclei

18. 3. 4 main phases of Mitosis a. _________ - DNA condenses into tightly coiled _____________. Nuclear envelope breaks down. _________ move to poles and ________ fibers form Centrioles chromosomes Nuclear envelope Spindle fibers

19. b. ___________ - Spindle fibers attach to each __________. Chromosomes align along cell _______ (middle) centromere What is the name of this structure?

20. c. _________ - Chromatids ________ to opposite sides of cell chromotids

21. d. _________ - Nuclear _________ starts to form. Chromosomes begin to uncoil and spindle fibers fall apart

22. 4. ___________ - division of cytoplasm. Different in ______ and _______cells.

23. III. Regulation of Cell Cycle (5.3) A. ________ and _______ factors regulate cell division 1. External factors a. Include physical and chemical factors b. Once a cell touches another cell it ______ dividing c. Many cells release chemical signals (_____________) that trigger cell growth.

24. 2. Internal factors a. External factors triggerinternal factors that affect cell cycle b. Two of the most important internal factors are kinases and cyclins

26. 3. __________ - programmed cell ______ (signals activate genes producing self-destructive _______

27. B. Cell division is uncontrolled in _______. 1. Cancer - common name for class or diseases characterized by ____________ cell division a. Form from disorganized clumps called________

28. b. Two types of tumors 1). ________ - cancer cells typically remain __________ together.

29. 2). _________ - Some cell break away (or ____________) from the tumor and spread through body

30. 2. Cancer cells come from normal cells that have suffered damage to ________ that make ________ involved in _____________ Brain cancer cells

31. a. damage from _________,________, _________, _________ radiation b. _____________ - Substances know to causecancer

32. c. Cancer can be treated with both ____________ and ___________.(these typically kill both cancerous and healthy cells)

33. IV. Asexual Reproduction (5.4) A. _______________is similar in function to mitosis 1. Reproduction occurs in two ways (______ and ______ reproduction)

34. a. ______ reproduction - joining of two specialized cells (_________ - egg and sperm), one from each parent 1). Offspring are genetically _________ 2). Mixture of _______ from both parents

35. b. __________ reproduction - creation of offspring from a single parent. Offspring genetically ____________

36. 2. Binary fission - asexual reproduction of single-celled organism a. Occurs in _____________ b. binary fission and _________ have similar results

37. B. Advantages and Disadvantages of Asexual reproduction 1.In environments that don’t change, _________ may be better. If they are well suited to environment may be more efficient 2. In changing environments__________ reproduction produces genetic ______ which raises chances for survival

38. V. Multicellular Life (5.5) A. Multicellular organisms depend on _____________ among different cell types. 1. Cells ____________ and ______________ in groups that form increasingly large, more complex structures

39. a. CELLS → _______ → ________ → ________ __________

40. b. ________ - group or cells that _____ _______to perform a particular function c. ______ - group of _______ that work together to perform specific function or related functions

41. d. Organ system - _______ that carry out similar ___________ 1). Organ systems work together to maintain ________________ 2). Occurs in ______ and ________

43. B. Specialized cells perform specific functions 1. Cell _____________ - process by which unspecialized cells develop into their mature _____ and __________ a. Every cell in body has full set of ____ b. Cells only use certain ______ and become________(ie. bone cells, mucscle cells, nerver cells, etc.)

44. C. Stem cells can develop into different cell types 1. ___________- unique type of body cell a. Can divide and renew themselves for long periods of time b. Remain ___________ in form c. Develop into a variety of specialized cell types

45. 2. Stem cells can be catorgorized by their ability or potential to develop into differentiated cell types and different tissues.

46. 3. _______ Stem Cells - partially _____________ cells located among the specialized cells or many organs and tissues 4. _________ Stem Cells - come from donated embryos grown in a clinic

47. 5. Research and Treatment Hope a. Stem cells have long been used to treat ________ and _______ b. Might be used to repair damaged ______ c. Used to cure diseases (i.e. _______)