1. MEIOSIS
Object: to study the meiosis through its subsequent developmental stages and discuss its Genetics Significant..

2. Meiosis
Meiosis in males is called spermatogenesis and produces sperms.
Meiosis in females is called oogenesis and produces ova.
Two divisions (meiosis I and meiosis II).

3. MITOSIS Somatic cells MEIOSIS Cells in sexual cycle
1 cell division:
2 daughter cells 2n 2n
MEIOSIS
Cells in sexual cycle
2 cell divisions:
4 cells product
of meiosis n n n 2n n n n
n=chromosome number

4. definitions
Homologous chromosomes: the members of a chromosome pair that is identical in the arrangement of genes

5. Homologous Chromosomes
eye color
locus
hair color
Paternal
Maternal

6. definitions Synapsis: (التشابك)
the intimate association ترابط وثيق)) of homologous chromosomes…
Homologous chromosomes

7. definitions Crossing-over: (العبور)
a term describing the process of reciprocal chromosomal interchange by which recombinants arise

8. Crossing over Pairing of homologous chromosomes Chiasma formation
Breakage
and joining
Recombinant

9. MEIOSIS I
Prophase I
The longest phase. This phase can be divided into 5 stages;
a) Leptotene
b) Zygotene
c) Pachytene
d) Diplotene
e) Diakinesis

10. Prophase I 1. Leptotene 2.Zygotene 3.Pachytene 4.Diplotene
5.Diakinesis
Prophase I

11. Metaphase I
Anaphase I
Telophase I
Prophase II
Prophase I

12. Meiosis 2nd division: like mitosis with haploid set

13. 4 Haploid cells Gametes

15. Mitosis vs Meiosis Mitosis Meiosis Results in 2 Diploid Cells (2N)
4 Haploid Cells (N)
Cells are
Genetically Identical
Genetically Different
Occurs in
Somatic (Body) Cells
Sex Cells

16. Slides for Meiosis I & II:
Prophase I

17. Metaphase I:

18. Anaphase I:

19. Telophase I:

20. Prophase II:

21. Metaphase II:

22. Anaphase II:

23. Telophase II:

24. Final result Mitosis : two genetically identical diploid cells
from one diploid parent cell
Meiosis :
Four genetically different haploid cells
from one diploid parent cell