1. Human Reproduction

2. Gametogenesis

3. Gametogenesis
Spermatogenesis refers to the process by which spermatozoa are produced from the germinal epithelium of the testis
Oogenesis is the process where ova is produced from germinal epithelium of the ovaries

5. Summary of the steps of spermatogenesis
Spermatogonia (2n) in germinal epithelium of seminiferous tubules
Mitosis
Primary spermatocytes (2n)
Meiosis (first division)
Secondary spermatocytes (n)
Meiosis (second division)
Spermatids (n)
sperm cells/spermatozoa

6. Spermatogenesis
At puberty, the germinal epithelial cells lining the seminiferous tubules start to produce sperms/spermatozoa by meiosis
Each germinal epithelium is diploid and in humans the diploid number is 46
Since the sperm is produced by meiosis, each one will be haploid with 22 single chromosome and X or Y chromosome

7. Spermatogenesis The process is as follows:
Cells of germinal epithelium become actively dividing cells called spermatogonia
Each spermatogonium, which is diploid (2n), enlarges to become a primary spermatocyte (also 2n)

8. Spermatogenesis
Primary spermatocyte undergoes the first meiotic division forming 2 haploid secondary spermatocytes
Each secondary spermatocyte undergoes the second meiotic division to produce 2 spermatids
Each spermatid matures to form a spermatozoan
Each spermatozoan is made up of a head, a middle-piece and a tail

12. Sperm
Microscopic cells produced by the male's testicles which can fertilize the female's ovum.
They are tiny, living cells 100 times smaller than a pencil dot. (the smallest cell in a man’s body
Enough sperm would fit on the head of a pin to re-populate the earth if each sperm fertilized an egg.
It is destroyed by warm body temperature, acidic environment.
It can survive in a women’s body for 5-8 days.
Any sperm not ejaculated are passed in the urine.

13. Oogenesis

17. Summary of the steps of oogenesis
Oogonia (2n) in germinal epithelium of seminiferous tubules
Mitosis
Primary oocytes (2n)
Meiosis (first division)
Secondary oocyte (n)
Meiosis (second division)
ootid (n)
ovum

18. Ova The female reproductive cell.
They are the largest cells in the female body. (about the size of a grain of sand.)
The female baby is born with all the ova she will ever have (about 200,000 in each ovary).
About ova mature and are released over a lifetime