1. CELL DIVISION Text: Mastering Basic Concepts (3rd), Bk1, pp.92-98

2. Types of cell division n 1. Mitotic cell division n 2. Meiotic cell division –(will be discussed in Ch.22: Genetics)

3. Mitotic cell division n Mitotic cell division consists of two parts: n 1. Mitosis –the division of the nucleus n 2. Cytoplasm division –the division of the cytoplasm

4. Mitosis n The nucleus divides into two identical daughter nuclei (sing. nucleus) n Therefore each daughter nucleus can carry the same function as it parent nucleus

5. Mitosis What can we find inside the nucleus? n Each nucleus carries many thread-like structures called chromosomes n Chromosomes carry the genetic materials called DNA (deoxyribonucleic acid)

6. Mitosis Structures of chromosome

7. Mitosis Stages of mitosis n 1. Cell growth –to make an copy of each chromosome n 2. The duplicated set is separated n 3. Each daughter nuclei receive one set of chromosomes

8. Cytoplasmic division starts

10. Cytoplasmic division n Cytoplasmic division follows mitosis n the cytoplasm is divided into two halves n mitotic cell division finishes after the completion of cytoplasmic division

11. Cytoplasmic division animal cell Two identical daughter cells

12. Cytoplasmic division plant cell

13. Mitosis Where mitosis occurs? n Mitosis takes place in most types of cells, excepts cells in the testes and ovaries. n In plants, mitosis occurs at the root tips and shoot tips

14. Mitosis Importance of mitotic cell division n 1. Growth n 2. Repairing the damage tissues n 3. Replacement of worn-out cells