1 / 46

Mitosis/Meiosis

Mitosis/Meiosis. How do your cells divide?. A few words before we start…. Haploid : ( n ) 1 set of unpaired chromosomes Diploid : (2n) 2 haploid sets of chromosomes (1 pair). Interphase. A Cell’s Life.

vinnie
Télécharger la présentation

Mitosis/Meiosis

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Mitosis/Meiosis How do your cells divide?

  2. A few words before we start….. • Haploid: (n) 1 set of unpaired chromosomes • Diploid: (2n) 2 haploid sets of chromosomes (1 pair)

  3. Interphase A Cell’s Life G1 is a growth phase. S phase is the synthesis phase or when DNA is replicated. During the G2 phase, organelles and molecules required for cell division are produced

  4. Why Do Cells Divide? Surface area to volume ratio Damaged cells Sex cells

  5. CellReproduction is either sexual or asexual

  6. Asexual Reproduction(one parent) • Binary Fission- • Budding • Vegetative Propagation • Regeneration

  7. DNA Structure Ch. 9 • Made up of nucleotides • There are 3 parts to each nucleotide • Deoxyribose sugar • Phosphate group • One of 4 Nitrogen bases

  8. T A C G C G Phosphate group Nitrogen Base Nucleotide Deoxyribose Sugar

  9. T A C G Nitrogen Bases There are four possible nitrogen bases: Adenine (A) Thymine (T) Cytosine (C) Guanine (G)

  10. T A C G Nitrogen Base Pairing These bases always pair together in DNA: Adenine (A) Thymine (T) Cytosine (C) Guanine (G)

  11. DNA Replication • Before a cell can divide the DNA must replicate (make a copy of itself)

  12. DNA Replication • Making a new strand of DNA is actually quite easy. • Replication occurs in 3 easy steps…

  13. 1. DNA Unzips • An enzyme unzips the molecule • The enzymes breaks the hydrogen bonds that hold the nitrogen bases together.

  14. T A C G C G DNA Replication DNA Unzips

  15. T A C G C G DNA Replication DNA Unzips

  16. T A C G C G DNA Replication DNA Unzips

  17. T A C G C G DNA Replication DNA Unzips

  18. T A C G C G DNA Replication DNA Unzips

  19. T A C G C G DNA Replication DNA Unzips Left Strand of Original DNA Right Strand of Original DNA

  20. 2. Base Pairing • Complementary bases match with each DNA strand in the open helix

  21. DNA Replication Base Pairing T A C G G C Left Strand Original DNA Right Strand Original DNA

  22. DNA Replication Base Pairing T T A C G G C Left Strand Original DNA Right Strand Original DNA New Right DNA Strand

  23. DNA Replication Base Pairing T T A C C G G C Left Strand Original DNA Right Strand Original DNA New Right DNA Strand

  24. DNA Replication Base Pairing T T A C C G G C C Left Strand Original DNA Right Strand Original DNA New Right DNA Strand

  25. DNA Replication Base Pairing T T A A C C C C G G Left Strand Original DNA Right Strand Original DNA New Right DNA Strand New Left DNA Strand

  26. DNA Replication Base Pairing T T A C C G G C C A G Left Strand Original DNA Right Strand Original DNA New Right DNA Strand New Left DNA Strand

  27. DNA Replication Base Pairing T T A C C G G G C C A G Left Strand Original DNA Right Strand Original DNA New Right DNA Strand New Left DNA Strand

  28. 3. DNA Zips Up • An enzyme zips the new molecules back up.

  29. T T T A A A C C C G G G C C C G G G DNA Replication • Voila! • Two identical strands of DNA!

  30. DNA Replication Review Step 3 Step 2 Step 1

  31. Remember - All this takes place in the S phase of INTERPHASE

  32. T T A A C C G G C C G G Now that DNA has replicated, we are ready to begin Mitosis (nucleus of the cell divides)

  33. It’s all about the chromosomes! • There are 46 in human body cells • The number of chromosomes remain constant during Mitosis Sister chromatids

  34. Parent Cell MITOSIS DNA condenses into chromosomes. The centrioles separate, and the spindle form. The nuclear envelope disappears. Prophase Chromosomes align on the equator. Each chromosome is connected to a spindle fiber at its centromere. Metaphase

  35. Sister Chromatids separate into individual chromosomes Anaphase Chromosomes gather at opposite ends. DNA uncoils and two new nuclear envelopes form. Telophase

  36. Cytokinesis • Cleavage (indention in cell membrane) or cell plate formation occurs. • Cell divides. Plant Cell Animal Cell

  37. Mitosis Animation

  38. Overview of the Cell Cycle

  39. Which Cells Go Through Mitosis? Cells which help the body in: Growth Repair Work The cells are called autosomes

  40. What happens if cell division gets out of control? • CANCER • The body doesn’t respond normally to the body’s control mechanisms • p. 127, 138-139

  41. Bone Cancer X-ray Ovarian Cancer Cell Dividing

  42. Skin Cancer

  43. Mitosis Review 1. Is the beginning parent cell diploid or haploid (2n or n)? 2. Are the daughter cells diploid or haploid (2n or n)?

  44. More Mitosis Review 3. How many daughter cells are produced? 4. Are the resulting daughter cells different from the parent cell?

  45. More Mitosis Review 5. Are the resulting daughter cells different from each other? 6. How many chromosomes are in a human parent cell? 7. How many chromosomes are in a human daughter cell?

  46. More Mitosis Review 8.What types of cells are produced by mitosis? 9. Why (when) does a cell go through mitosis?

More Related