1. Cell Reproduction
Chapter 4

2. Cell Growth and Division Chapter 4-1
Cells undergo division to:
Increase in number
Repair worn out cells
Replace cells that have died

3. Cell cycle Interphase – most of the life of any cell
period of growth and development
DNA replication
growth and preparation for mitosis
Nerve and muscle cells don’t divide remain in interphase
Skin cells constantly change

4. Mitosis
The process in which the nucleus divides to form two identical nuclei.
It is a series of phases or steps.

5. Animal Mitosis Interphase – Nucleus can be seen DNA is replicating
(making exact copies)

6. Prophase – Chromosomes visible Nucleolus and nuclear membrane fade
Centrioles move to opposite end of cell
Spindle fibers begin to stretch across the cell

7. Metaphase-
Double strands of chromosomes line up across the center of cell
Attach to a spindle

8. Centromere – place where double stranded chromosomes are held together

9. Anaphase Anaphase Centromeres divide Two strands separate
Separate strands move away toward opposite ends of cell

10. Telophase Centrioles and spindles disappear
Chromosomes stretch out and become harder to see

11. Nuclear membrane forms around each mass of chromosomes
New nucleolus appears
Cell begins to split by pinching at cell membrane

12. Daughter cells – new cells that divided from a parent cell
Interphase

13. Mitosis
                                      

14. Mitosis in Plant Cells All phases are the same as animal cells
Telophase
Cell wall is produced to separate the cells.
                                      

15. http://www. biology. arizona

16. Identify each phase of mitosis below.

17. Identify animal mitosis

18. Results of Mitosis Two Important results of mitosis:
Nucleus was divided
Two new nuclei are identical

19. Cytokinesis
The period of the cell cycle when the cell separates into two daughter cells
Animal cell cytokinesis – cell membrane pinches in the middle and a new membrane is formed
Plant cell cytokinesis – cell wall is formed between the two daughter cells, then a cell membrane forms and completely separates.  .