SPERMATOGENESIS process of spermatogenesis oogenesis life sciences SPERMATOGENESIS process of spermatogenesis oogenesis life sciences SPERMATOGENESIS process of spermatogenesis oogenesis life sciences SPERMATOGENESIS process of spermatogenesis oogenesis life sciences SPERMATOGENESIS process of spermatogenesis oogenesis life sciences Vitellogenesis Oogenesis SPERMATOGENESIS process of spermatogenesis oogenesis life sciences Vitellogenesis Oogenesis

1. HEMCHAND YADAV UNIVERSITY, DURG
Session 2023-
24
DEPARTMENT OF ZOOLOGY,
PT. DEVI PRASAD CHAUBEY GOVT COLLEGE, SAJA
SPERMATOGENESIS
Presented by
Dhameshwar Sahu
M.Sc. 2nd Sem

2. CONTENT
• INTRODUCTION
• DEFINATION
• PROCESS OF SPERMATOGENESIS
• STRUCTURE OF SPERm
• SIGNIFICANCE
• CONCLUSION

3. INTRODUCTION
• It refers to the formation of spermatozoa.
Spermatozoa are formed in the testies.In each
vertebrate, a pair of testies are found.Each
testies is attached to the dorsal body wall by a
connective tissue membrane called
mesorchium.

4. DEFINATION
The process of formation of sperm is called
spermatogenesis. The seminiferous tubules are
lined by germinal epithelium consists largely of
cuboidal primary or primordial germ cell and
contains certain tall somatic cells called Sertoli
cells. Spermatogenesis also include process of
formation of spermatids and spermatozoa.

5. T. S. Of Testies

6. The process of spermatogenesis
 Formation of spermatids
A. Multiplication Phase
B. Growth Phase
C. Maturation Phase
 Spermiogenesis

7. FORMATION OF SPERMATID
The premordial germ cell of testes forms spermatids. It has
three phase
A. Multiplication Phase :-The primary germ cell that present in
the seminiferous tubule form spermatogonia (2n) by mitotic
division .

8. CONTINUE
B. Growth Phase :- The spermatogonia increase in
size by accumulation of nuclear material and attain
maturity ,called as primary spermatocytes(2n).
C. Maturation Phase :- Here two maturation division
occurs. Firstly, primary spermatocytes form
secondary spermatocytes (n) by reduction division of
meiotic-I . Again secondary spermatocytes form
spermatids(n) by meiotic –II .

9. SPERMEOGENESIS
The process by which rounded nonmotile
spermatids are converted to active and mobile
sperms is called Spermeogenesis .
1.The nucleus shrinks ,chromosome become closely
packed.
2.All nuclear material (except DNA) get lost.
3.The sperm nucleus become elongated and narrow.

10. CONTINUE
4.The spermatid contain two centriole in the
centrosome which move to lie behind the nucleus.
5.All mitochondria spirally arranged in the middle
piece of spermatozoa.
6.The Golgi apparatus form acrosome .
7.Most of cytoplasm are eliminated and remaining
forms a condensed layer surrounding the middle
piece.

11. STAGES OF SPERMEOGENESIS

12. STRUCTURE OF SPERM
• IT HAS TWO PARTS
A. HEAD
B. TAIL
 HEAD : IT HAS NUCLEUS AND ACROSOME WITH A
TRIANGULAR SHAPE. ACROSOME IS DOUBLE
LAYERED AND CAP LIKE STRUCTURE. THE
NUCLEUS CONTAIN CONCENTRATED DNA .

13. CONTINUE
• Tail : Tail is the longest part of a sperm provides
locomotion to the sperm. It is divided into 3 sub-
divisions i.e., neck, middle piece and end piece.
Neck contains two centrioles(one proximal &
other is distal). The middle piece bear tightly
coiled mitochondria which supplies energy for
motility of sperms. The end piece contain two
central fibers surrounded by 9 peripheral fibers.

14. FIGURE SHOWING STRUCTURE OF SPERM

15. SIGNIFICANCE
• Spermatogenesis is required to maintain the fixed
number of chromosomes in the individuals of a
species.
• Sperms carry genetic information from one
generation to the next generation. The
spermatogonial stem cells can be used to preserve
the genetic pool of endangered species.

16. CONCLUSION
• During spermatogenesis, one spermatogonium
produces four sperms. The sperms have half number
of chromosomes.
• During meiosis-I crossing over takes place which
brings about variation. Spermatogenesis occurs in
various organisms.