Sexual reproduction

1.

2.

Sexual reproduction is the
production of new offsprings from
two parents.
Sexual reproduction is the
combination of one set of genetic
material from two organisms of the
same species, but opposite sex,
resulting in a new organism with new
gene combination.

3.

GAMETES
•Sexual reproduction occurs by
means of gametes.
•They are produced in reproductive
organs by means of meiotic cell
division
Gametes have n number of
chromosome.

4.

5. Organs which produce gametes are called Gonads.

•Organs which produce
gametes are called Gonads.
•Male gonad is called testes
that produce sperm .
Female Gonad is called ovary
that produce egg.

6. Production of Gametes

Production of male or female
gametes are called
Gametogenesis.
Especially production of sperm
is called Spermatogenesis.
Production of egg is called
oogenesis.

7. FERTILIZATION

The union of egg and sperm is
called FERTILIZATION.
The cell that is formed from union
of an egg and sperm is called
ZYGOTE.
Gametes have n number of
chromosome and zygote has 2n
number of chromosome.

8. Steps of Sexual Reproduction

testis
ovary
Meiosis
sperms
Meiosis
fertilization
zygote
embryo
foetus
baby
eggs (ova)

9. POLLINATION

10.

•Trаnsfer of pollen from anther
to stigma is called pollination.
• Pollination occurs by means of
wind,water, insects and other
animals

11.

12. After pollination;

A pollen tube grows down through
the stigma and stylus into the
ovary.
The tube nucleus controls the
formation of pollen tube.
Then pollen tube enters the ovule
through the microphyle
The tube nucleus and generative
nucleus pass from pollen grain to

13. FERTILIZATION

The generative nucleus is divided into
two sperm nuclei in the pollen tube.
2 Sperm nuclei enter the embryo sac.
One sperm fertilizes to egg cell to form
ZYGOTE.
Other sperm fuses with pollar nüclei to
form triploid (3n) ENDOSPERM.
This type of fertilization is called
Double Fertilization.

14.

15. SEED AND FRUITS

After the fertilization, each
ovule develops to seed.
The ovary develops to fruit.