Spermatogenesis is the process by which sperm cells are produced in the testes. It begins at puberty due to increased levels of hormones like GnRH, LH, and FSH. The process involves four stages: multiplication of spermatogonia, growth and maturation of spermatocytes, transformation of spermatids into spermatozoa through spermiogenesis, and release of mature sperm from the seminiferous tubules. Mature sperm have a flattened head containing genetic material and a tail that allows for motility.

1. Swami Atmanand Govt.
English Medium school,
Bijapur ,(cg)
NAME :- ANUSHARANI GADE
CLASS :- XII “ PCB”
ROLL NO. :- 05
TOPIC :- SPERMATOGENESIS

2. 🏷️INDEX ......
 Introduction
 Spermatogenesis
 Hormones Essential for spermatogenesis
 Stages of spermatogenesis
 Structure of a sperm

3. Introduction
The process of formation of haploid gametes from the undifferentiated diploid germ cells in the gonads, for
sexual reproduction is called gametogenesis. Gametogenesis in human beings is of two types, i.e.
Spermatogenesis (in males) and oogenesis (in females).sperm, also called spermatozoon, plural spermatozoa,
male reproductive cell, produced by most animals. With the exception of nematode worms, decapods (e.g.,
crayfish), diplopods (e.g., millipedes), and mites, sperm are flagellated; that is, they have a tail. In higher
vertebrates, especially mammals, sperm are produced in the testes. The sperm unites with (fertilizes) an ovum
(egg) of the female to produce a new offspring. Mature sperm have two distinguishable parts, a head and a
tail.In humans it is flattened and almond-shaped, it consists of genetic substances, called chromosomes, which
are responsible for transmitting specific characteristics of an individual,The sperm cells also carry the X or Y
chromosome that determines the sex of the future child.

4. Spermatogenesis
It is the formation of spermatozoa (sperms) in testes, which originate
from the Primordial Germ Cells (PGCs). The process of
spermatogenesis starts at puberty.

5. Hormones Essential for Spermatogenesis
Hormones Essential for Spermatogenesis Spermatogenesis initiates due to a significant increase in the
secretion of Gonadotropin Releasing Hormone (GnRH) by hypothalamus at the age of puberty. The
increased level of GnRH acts at anterior pituitary and stimulates the secretion of two gonadotropins, i.e.
Luteinizing Hormone (LH) and Follicle Stimulating Hormone (FSH). LH acts on the Leydig cells stimulating
the synthesis and secretion of androgens, which in turn stimulate the process of spermatogenesis.
FSH acts on Sertoli cells and stimulates the secretion of some factors which help in spermiogenesis.
Androgens are testicular hormones which function to maintain the accessory ducts and glands in males.

6. Stages of Spermatogenesis
(this include four steps)
1. MULTIPLICATION
PHASE
The undifferentiated germ cells present on
the inside wall of seminiferoustubules of the
testes are called spermatogonia (sing:
spermatogonium) or sperm mother cells
Tubules of the testes are called
spermatogonia (sing: spermatogonium) or
sperm mother cells.
They increase in number by repeated
mitotic divisions so that the newly formed
spermatogonium possesses the same
number of chromosomes. Each
spermatogonium is diploid and contains 46
chromosome
2. GROWTH PHASE
Some of the spermatogonia
differentiate to form primary
spermatocytes.
3 MATURATION
PHASE
Formation of spermatids Each of
these primary spermatocytes
undergoes first meiotic division
and produces two secondary
spermatocytes (23 chromosomes)
each of which further undergoes
second meiotic division
The spermatids transform into
spermatozoa (sperms) by the
process called spermiogenesis

7. Fig :- Diagrammatic sectional view of a
seminiferous tubule ( enlarged)

8. 4. DIFFERENTIATION
PHASE
After spermiogenesis, sperm heads get
embedded in the Sertoli cells and are
finnally released from the seminiferous
tubules by the process of spermiation .
Fig :- Schematic representation of
Spermatogenesis in human male

9. Structure of a sperm (spermatozoa)
m

10. “
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Thankyou.
THE END