The Cell Cycle & Cellular Division

1. The Cell Cycle & Cellular Division

2. I. Cell Division: • All _______ are derived from preexisting cells (Cell Theory). • _______________ is the process by which cells produce new cells. cells Cell division

3. I. Cell Division: • Cells grow in number, NOT in size. • Smaller cells more efficient (cellular transport, cellular communication) • Easier to take in nutrients and get rid of wastes.

4. How Often Do Cells Divide? • Some cells must be repaired often such as cells lining the ____________, ____________________, and ____________ with a short lifespan. • Other cells DO NOT divide at all after birth such as ________, nerve cells, _____________, and __________________. intestines white blood cells skin cells muscle brain cells female egg cells

5. II. Reasons for Cell Division: • Cell ________ • ________ and _____________ of damaged cell parts • Growth and development of an ________ growth Repair replacement embryo

6. IV. Chromosomes & their Structure: • The plans for making cells are coded in _____. • DNA, deoxyribose nucleic acid, is a long, thin molecule that stores ___________________. • DNA is organized into giant molecules called ______________. DNA genetic information chromosomes

7. IV. Chromosomes & Their Structure: Chromosomes • ________________ are made of protein and a long, single, tightly-coiled DNA molecule visible only when the cell divides. • When a cell is NOT dividing the chromosome (DNA) is less visible and is called ___________. chromatin

8. IV. Chromosomes & Their Structure: Centromeres • _____________ hold duplicated chromoses together before they are separated in mitosis. • When DNA makes copies of itself before cell division, each half of the chromosome is called a __________________ • Each sister chromatid contains ____________ genetic information. sister chromatid identical

9. VI. Cell Cycle & Cell Division: • Eukaryotes (nucleus and membrane-bound organelles) must be copied exactly so the two new cells formed division will be _______________ • The original parent cell and two new ________________ must have IDENTICAL chromosomes. • Ex: Humans have 46 chromosomes in our _____________ (body cells). After one of these somatic cells goes through mitosis, two daughter cells are produced each having 46 chromosomes (genetically identical). exactly alike daughter cells somatic cells

10. VI. Cell Cycle & Cell Division: • Both the nucleus (_________) and the cytoplasm (_____________) must be divided during cell division in eukaryotes. mitosis cytokinesis

11. VI. Cell Cycle & Cell Division: • Cells go through phases or a cell cycle during their life before they divide to form new cells. • Cell cycle is about _______ hours for most animal cells. • Cell cycle is controlled by proteins and _________. 12-24 enzymes

12. VI. Cell Cycle & Cell Division: • The cell cycle includes 3 main parts - - - ____________, _________, and _____________. • _________ = nuclear division • _____________ = division of cytoplasm interphase mitosis cytokinesis mitosis cytokinesis

13. A. Interphase: • Interphase is the _________ part of a cell’s life cycle and is called the “resting stage” because the cell isn’t dividing. Animal Cell Plant Cell nucleus longest

14. A. Interphase: • Divided into 3 stages: • ____ (Gap 1) = cell is growing, carrying out normal cell functions, preparing to replicate DNA. - Cells mature and increase in size by making more ___________ & ____________ G1 cytoplasm organelles

15. A. Interphase: 2) ___ (synthesis) = DNA is copied or ___________ - DNA is in the form of ___________ (uncoiled DNA) and is NOT _________ S replicated chromatin visible

16. A. Interphase: G2 3) ____ (Gap 2) = cell prepares for nuclear division (mitosis) - cell makes all the structures needed to ________ divide

18. B. 4 Stages of Mitosis: • Division of the nucleus or _________ occurs first. • Mitosis is an _________ method of reproduction • Only _____ parent cell • Daughter cells have SAME number of _____________ (genetic info) • Mitosis consists of 4 stages - - - prophase, metaphase, anaphase and telophase. replicated asexual one chromosomes

19. 1. Prophase: • _________ phase of MITOSIS • Chromatin (______________) condenses and coils into the form of chromosomes • Chromosomes are visible (shaped like a “X”) • ___________________ (half of a “X”) attach to each other by the ____________ Longest uncoiled DNA Sister chromatids centromere

20. 1. Prophase: • Centrioles in animals cells move to opposite ends of cell. • Spindle forms from each centriole (ONLY in ________ cells) • _______ cells ________ have centrioles (spindle forms from a microtubule) • __________________ dissolves (disappears) • ___________ disintegrates animal Plant DO NOT Nuclear membrane Nucleolus

21. 1. Prophase:

23. 2. Metaphase: • __________ phase of MITOSIS • Chromosomes line up in center or _________ of the cell • The centromere of each chromosome attaches to spindle fibers. Shortest equator

24. 2. Metaphase:

26. 3. Anaphase: • Spindle fibers attached to the centriole pull the ___________________ apart at their centromere. • Separated chromosomes travel along the ________________ to the poles (ends) of the cell. sister chromatid spindle fibers

27. 3. Anaphase:

29. 4. Telophase: • __________________ forms at each end of the cell around the chromosomes. • ___________ reforms • Spindle fibers begin to break down • Chromosomes become less tightly coiled and appear as ___________ again • Cytokinesis begins Nuclear membrane Nucleolus chromatin

30. 4. Telophase:

32. Mitosis Animation • http://www.sumanasinc.com/webcontent/animations/content/mitosis.html

33. C. Cytokinesis: • _____________ = division of the cytoplasm of the cell and its organelles separate into 2 new daughter cells. Cytokinesis

34. C. Cytokinesis: • In _________, a groove called the _________________ forms pinching the parent cell in two. animals cleavage furrow

35. C. Cytokinesis: • In ________, a ____________ forms down the middle of the cell where the new __________ will be plants cell plate cell wall

36. C. Cytokinesis:

37. VI. Cancer: • Cell division must be controlled, otherwise cell growth will occur without limit (cancer) • _____ mutations lead to changes in the proteins/enzymes that regulate the cell cycle DNA Cancerous Kidney Cells

38. VI. Cancer: • ________ = a cell or group of cells that grown out of control and create a tumor. • Crowds out normal cells and results in the loss of tissue function. Cancer Cancerous Kidney Cells

39. VI. Cancer: • _______ = mass of growing, unregulated cells • 2 types of tumors: • ________ - tumor that does not spread • ___________ - tumor that spreads and destroys healthy tissue Tumor Benign Malignant

40. Causes of Cancer: • __________ (family history) • _________ • _____________ (cancer causing chemicals) • _________: • HPV can lead to cancer of reproductive organs • ___________: • Sunlight (UV) – skin cancer Genetics Smoking Carcinogens Viruses Radiation

41. What phase of the cell cycle would this be?

42. What phase of the cellcycle would this be?

43. What phase of the cellcycle would this be?

44. What phase of the cellcycle would this be?

45. Can you identify 5 stages?

46. Mitosis occurring in ANIMAL CELLS

47. Mitosis occurring in PLANT CELLS