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

5. Why do animals shed their skin?

6. The process of asexual reproduction begins after a sperm fertilizes an egg.

7. Two reasons why cells reproduce by mitosis: 1. Growth 2. Repair
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.

8. Mitosis Cycle Interphase Prophase Metaphase Anaphase Telophase
Interphase
Prophase
Metaphase
Anaphase
Telophase

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

11. Interphase Plant Cell Animal Cell
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12. 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

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

14. Metaphase 2nd step in Mitosis
Chromatids (or pairs of chromosomes) attach to the spindle fibers at the centromere.
Centrioles
Spindle fibers

15. Metaphase Plant Cell Animal Cell
Photographs from:

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

17. Anaphase Plant Cell Animal Cell
Photographs from:

18. Telophase 4th step in Mitosis
Two new nuclei form.
Chromosomes appear as threads again
Mitosis ends.
Nuclei
Nuclei
Chromatin

19. Telophase Plant Cell Animal Cell
Photographs from:

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

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

22. Can you identify the stages of mitosis on the onion slide?