Spermatogenesis Process
Spermatogenesis is process of forming sperm or spermatozoa. It take place in seminiferous tubule of testis. It starts after the puberty.
It starts from the cells of the seminiferous tubule called spermatogonial stem cells. Cells of seminiferous tubule undergoes mitosis to form sperm cell, called Spermatogonial stem cells, then undergo changes to form two primary spermatocyte. Then via meiosis I primary spermatocyte develop into secondary spermatocyte. Secondary spermatocyte are divide into four equal spermatids by meiosis II. The spermatid four are transformed into the mature spermatozoa by the process of spermatogenesis and achieved maturation. It is called as sperm cells or mature spermatozoa.
Spermatogenesis is similar to the process of oogenesis in females. It take place after the puberty and continues till the death of person. It take 70 days to occur spermatogenesis completely.
Spermatogenesis take place as Spermatogonium cells – primary spermatocytes – secondary spermatocytes – spermatid – sperm
Process of spermatogenesis take place in testis which is remain lower in temperature compared to other body area temperature. It is important to make lowered temperature for good formation of sperm.
It starts from the cells of the seminiferous tubule called spermatogonial stem cells. Cells of seminiferous tubule undergoes mitosis to form sperm cell, called Spermatogonial stem cells, then undergo changes to form two primary spermatocyte. Then via meiosis I primary spermatocyte develop into secondary spermatocyte. Secondary spermatocyte are divide into four equal spermatids by meiosis II. The spermatid four are transformed into the mature spermatozoa by the process of spermatogenesis and achieved maturation. It is called as sperm cells or mature spermatozoa.
Spermatogenesis is similar to the process of oogenesis in females. It take place after the puberty and continues till the death of person. It take 70 days to occur spermatogenesis completely.
Spermatogenesis take place as Spermatogonium cells – primary spermatocytes – secondary spermatocytes – spermatid – sperm
Purpose
Spermatogenesis is similar to oogenesis of the female gamete. It involve series of steps lead to formation of sperm or spermatozoa. It is vital fluid necessary to conceive ovum in female. The purpose of spermatogenesis is to convert diploid (2n) number of chromosome to haploid (n) number of chromosome. Haploid number of chromosome consist of parenteral chromosome that form by undergoing various DNA changes by DNA damage response. It make unique form of haploid chromosome that are unique and not similar to parent cell. It then mates with female gamete ovum which has haploid number of chromosome both together fuses to form diploid cell (a baby).Duration
Average time span of spermatogenesis is 70 to 120 days. There are millions of sperm create daily, however of 100 to 150 million of them become mature spermatozoa. To form a mature sperm, it takes approximately 3 months to complete.Location in humans
Spermatogenesis begins at the seminiferous tubule cells. From there spermatogonial cell develops. Initial states occur in the testis. It then send to epididymis where the gamates are mature and stored until ejaculation. Maturation take place in the epididymis.Process of spermatogenesis take place in testis which is remain lower in temperature compared to other body area temperature. It is important to make lowered temperature for good formation of sperm.
Spermatogenesis Process :-
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- Initiation:-
Spermatogenesis starts from the stem cells of the seminiferous tubule. Stem cells undergoes a mitotic division to form spermatogonium. It then undergoes mitotic division to form a diploid number of primary spermatocyte.
- Primary spermatocyte:-
Primary spermatocyte has diploid number of chromosome. It undergo meiosis next which two haploid number of secondary spermatocyte. Secondary spermatocyte are different to parent cell because it undergo genetic changes, chromosomal change during meiosis.
It undergo meiosis with DNA change by DNA damage response. It then form a new unique haploid number of chromosome which is different from parent cells.
Primary spermatocyte simultaneously undergo meiosis II to form haploid number of secondary spermatocyte.
It undergo meiosis with DNA change by DNA damage response. It then form a new unique haploid number of chromosome which is different from parent cells.
Primary spermatocyte simultaneously undergo meiosis II to form haploid number of secondary spermatocyte.
- Spermatidogenesis
Spermatidogenesis is explained as formation of four spermatid from secondary spermatocyte. Secondary spermatocyte undergoes meiosis producing 4 spermatids. The spermatid undergoes spermiogenesis to form the mature spermatozoa.
- Spermiogenesis
Spermiogenesis is the last stage of spermatogenesis in which sperm undergo maturation. In this sperm develop structural component and enter into testis furthermore achieved motility.
In spermiogenesis, Sperms remove cytoplasm, unnecessary cells and tissues after which they released in seminiferous tubule. From there by muscle contraction, they reach epididymis and acquired motility.
In spermiogenesis, Sperms remove cytoplasm, unnecessary cells and tissues after which they released in seminiferous tubule. From there by muscle contraction, they reach epididymis and acquired motility.
Role of Sertoli's cell
Sertoli cells are present in seminiferous tubules. They form by follicle-stimulating hormone nourishing the sperm cells at each stage of spermatogenesis. Its functions are: -
- Maintain an atmosphere for developing sperm
- Secrete vital fluids
- Phagocytosis in the cytoplasm to remove unnecessary substances during spermiogenesis
- Protect spermatid from the immune system by maintaining the blood-testis barrier
Key terms:-
- Mitosis: - type of cell division in which nucleus divides into nuclei with the same number of chromosome (diploid chromosome)
- Meiosis:- Cell division resulting in the haploid number of cell formation
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