1. The Importance of Mitosis

2. The need to heal!

3. The need to grow!

4. DNA Made of nucleotides Phosphate sugar Nitrogen base Adenine Guanine
Cytosine
thymine

5. Coiling Uncoiled DNA called chromatin- between cell divisions
Happens during cell division
DNA wraps tightly around proteins called histones

6. Chromosomes
Chromosome- consists of two identical halves connected together by a cnetromere
Chromatid- a half of one chromosome.
Contains one complete set of information
Copies itself to make the other chromatid

7. How many chromosomes??
Each human diploid cell is 2N and contains 46 total
23 identical pairs
( 23 x 2 = 46 ) “homologous chromosomes”
carry the same traits

8. How many chromosomes?? Egg and sperm cells only carry one set of 23
Each human haploid cell is “N”
Egg and sperm combine to form 2N or 46
All other chromosomes are called autosomes
Each human or animal cell has sex chromosomes XX or XY
Define the sex of the organism

9. Cell Cycle G1 = cell grows S = DNA replication G2= Prepare to divide
M= Mitosis
INTERPHASE

10. , etc…
Quicktime video

11. Stages of Mitosis
Prophase
Metaphase
Anaphase
Telophase
Cytokinesis

12. Birth of a Brain Cell
Quicktime movie

13. TWO REASONS FOR MITOSIS
Healing/Repair
Growth
THE NEXT SLIDES ARE GRAPHIC

14. REASON FOR MITOSIS

15. Let the healing begin

17. Better

18. Much better

19. Mitosis in onion root tip
Why onion root tip?
Actively growing, lots of cells dividing (mitosis)
Where exactly should you look on the microscope slide?

22. Cell division differences in plant vs animal cells
Which is the animal cell and which is plant?
Which stage of mitosis is being shown?
CLEAVAGE FURROW
CELL PLATE

23. Stages of mitosis id: slide #1

24. 2 and 3

25. 4 and 5

26. 6 and 7

27. 8 and 9

28. 10, 11, 12

29. 13, 14, 15

30. 16, 17, 18

31. YOUR QUIZ ON MITOSIS IS TOM.
Here’s what you need to be able to do…