1. The fingerprint that’s inside your body!!!!!!
DNA
The fingerprint that’s inside your body!!!!!!

2. DNA

3. DNA (Deoxyribonucleic Acid)
DNA is the genetic material of the cell.
Model of DNA built in 1953
by James Watson &
Francis Crick.
Twisted ladder: double helix
A chemical that contains information for an organism’s growth & functions.
Made of two strands of molecules joined in a structure that looks like a twisted ladder

4. Fun DNA Facts!
DNA is too small to see, but under a microscope it looks like a twisted up ladder!
DNA stands for: D: Deoxyribose N: Nucleic A: Acid
Every living thing has DNA. That means that you have something in common with a zebra, a tree, a mushroom and a beetle!!!!

6. Chromosomes Compact sections of DNA Found in the nucleus
Before cell division, the chromosomes compact more and become visible under a light microscope
Chromosomes duplicate and are seen as two identical structures called chromatids that are held together by a centromere.

7. ghr.nlm.nih.gov
macroevolution.net
biologycorner.com

8. Each species has a constant number of chromosomes
Humans have 46
Fruit flies have 8
Corn plants have 20

9. Cell Division is Involved in Growth, Development, & Repair/Replacement
Growth: a larger organism has more cells than a smaller organism, not larger cells
Development: cells specialize and take on specific functions; they have the same genetic material as all the other cells
Repair/Replacement: Organisms repair injuries by cell division; as cells age and die, cells are replaced

10. Your skin loses about 40000 cells ~every minute
Your skin loses about cells ~every minute. Skin cells take hours to be replaced.
Brain cells live a long time.
Nerve cells: never
Liver cells: a year or more
Bacteria: 20 minutes

12. Any activity or set of events that regularly repeats.
Examples:
The four seasons
Months of the year
Events that make your heart beat

13. All living things live, grow, reproduce, and die in a process called a life cycle.
Life cycle of a tree vs Life cycle of a butterfly?
Cells have a life cycle: the cell cycle.

14. The Cell Cycle
The normal sequence of development and division of a cell.
Two main phases: Interphase & Cell division

15. Interphase Longest part of the cell cycle Cell grows about 2x
Cell engages in normal life activities
G1 (Growth 1)
S (Synthesis) - DNA copies
G2 (Growth 2) - cell prepares for division

16. Cell Division Phase Include Mitosis & Cytokinesis
Mitosis: The part of cell cycle during which the nucleus divides
The function is to move the DNA and other material in parent cell into position for cell division.
Cytokinesis: division of the cytoplasm

17. Reproduction
Growth
Development
Repair/Replacement

18. Mitosis
Cell Division
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19. Cell division
All complex organisms originated from a single fertilized egg.
Every cell in your body started here; through cell division the numbers increased.
Cells then specialized and changed into their various roles.

20. Parent cell
Chromosomes are copied and double in number
Chromosomes now split
2 daughter cells identical to original

21. Mitosis
All daughter cells contain the same genetic information from the original parent cell from which it was copied.
Every different type of cell in your body contains the same genes, but only some act to make the cells specialized – e.g. into nerve or muscle tissue.

22. Mitosis – bone cell slides2 1
Cells split
Chromosomes copied
Parent cell 3 4 5
2 daughter cells
Copies separating

23. Plants

24. Rat – epithelial cells

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

28. Why do animals shed their skin?

29. Three reasons why cells reproduce: 1. Growth 2. Development 3
Three reasons why cells reproduce: Growth Development Repair/ Replacement
Skin cancer - the abnormal growth of skin cells - most often develops on skin exposed to the sun.
Cell that reproduce by asexual reproduction reproduce constantly.

30. Animated Mitosis Cycle
Interphase
Prophase
Metaphase
Anaphase
Telophase & Cytokinesis

31. The next slide is the beginning of the back side of your notes
The next slide is the beginning of the back side of your notes. Fill in the blanks as well as draw what the cell looks like at each phase. Label all the parts that the slide shows you.

32. Cell division occurs in a series of stages, or phases.

33. Interphase occurs before mitosis begins
Chromosomes are copied (# doubles)
Chromosomes appear as threadlike coils (chromatin) at the start, but each chromosome and its copy(sister chromosome) change to sister chromatids at end of this phase
CELL MEMBRANE
Nucleus
Cytoplasm

34. Sister chromatids attached with the centromere

35. Interphase Plant Cell Animal Cell
Photographs from:

36. Prophase 1st step in Mitosis
Mitosis begins (cell begins to divide)
Centrioles (or poles) appear and begin to move to opposite end of the cell.
Spindle fibers form between the poles.
Centrioles
Sister chromatids
Spindle fibers

37. Prophase Plant Cell Animal Cell Spindle fibers Centrioles
Photographs from:

38. Metaphase 2nd step in Mitosis
Chromatids (or pairs of chromosomes) attach to the spindle fibers and line up in the middle of the cell.
Centrioles
Spindle fibers

39. Metaphase Plant Cell Animal Cell
Photographs from:

40. Anaphase 3rd step in Mitosis
Chromatids (or pairs of chromosomes) separate and begin to move to opposite ends of the cell.
Centrioles
Spindle fibers

41. Anaphase Plant Cell Animal Cell
Photographs from:

42. Telophase 4th step in Mitosis
Two new nuclei form.
Chromosomes appear as chromatin (threads rather than rods).
Mitosis ends. (two new nuclei have formed)
Nuclei
Nuclei
Chromatin

43. Telophase Plant Cell Animal Cell
Photographs from:

44. Cytokinesis occurs after mitosis (cytoplasm divides)
Cell membrane moves inward to create two daughter cells – each with its own nucleus with identical chromosomes.

45. Cytokinesis In animal cells: the cell pinches inward.
In plants: a cell plate forms between the two new cells. This becomes the new cell wall.

46. Animal Mitosis -- Review
Interphase                                                             
Prophase                                                             
Metaphase                                                             
Anaphase                                                             
Telophase                                                             

47. Plant Mitosis -- Review
Interphase                                                             
Prophase                                                             
Metaphase                                                             
Anaphase                                                             
Telophase                                                             

48. Cell Cycle

49. - Cell Division
The Cell Cycle 50

50. Mitosis Animation

52. Why must organisms reproduce?? Reproduction: production of offspring
Sexual Reproduction vs Asexual Reproduction
Sexual reproduction requires two different cells (2 parents)
Simple organisms such as most bacteria and some protists reproduce asexually
Only one “parent” is needed