KERALA UNIVERSITY COLLEGE OF TEACHER EDUCATION NEDUMANGAD

FERTILIZATION IS A FUSION OF

MALE GAMETES WITH FEMALE

GAMETES

FLOWER HAS FOUR FLORAL WHORLS

CALYX

COROLLA

ANDROECIUM

GYNOECIUM

NON-ESSENTIAL WHOLS ARE STERILE PARTS WITH NO REORODUCTIVE ROL

ESSENTIAL WHOLS ARE FERTILE PARTS ,THEY ARE DIRECTLY INVOLVED IN

SEXUAL REPRODUCTION

NON-ESENTIAL WHORLS

ESSENTIAL WHORLS

ANDROECIUM

GYNOECIUM

COROLLA

CALYX

◑ANDROECIUM IS THE MALE PART

OF THE FLOWER.

◑IT CONSISTS OF STAMENS OR MICRO

SPORANGIA

◑Gynoecium is the female part of a

flower

◑It consists of carpel or

megasporophyll.

MALE AND FEMALE SEX ORGANMALE SEX ORGAN FEMALE SEX ORGAN

• STAMEN IS A MALE

REPRODUCTIVE ORGAN

• IT CONSISTS OF THREE PARTS

→Filament [stalk of a flower]

→Anther[two lobed structure]

→Connective[it connect filament and anther]

CARPEL

CARPEL IS THE FEMALE

REPRODUCTIVE ORGAN.

IT CONSISTS OF THREE PARTS

→Stigma[terminal parts where pollen

grain deposited during pollination.]

→Style[long tubular parts]

→Ovary[fertile basal part contain

ovule]

STIGMA

STYLE

OVARY

♦ ANTHER IS A PART OF STAMEN

♦INSIDE THE ANTHER POLLEN GRAINS

ARE FORMED.

♦MATURE POLLEN GRAIN GO TO

DIVISION FORM TWO UN-EQUAL CELLS.

→Large Vegetative Cell –It Act As Pollen Tube.

→Small Generative Cell- Produces Two Male

Gametes /Sperm By Division.

DEVELOPMENT OF CARPEL/MEGASPOROPHILL

◑Ovule is the oval structure found inside

the megasporophill.

◑Mature ovule consists of a central mass of

tissue called nucelous.

◑Apical part of ovule is called micropyle.

◑Basal part of ovule is called chalaza.

◑Lying embedded in the nucelous at the

micropylar end is called embryo sac.

MICRO PYLE

EMBRYO SAC

CHALAZA

P0LLINATION

MATURE EMBRYO SAC

IT IS A SEVEN CELLED STRUCTURE.

3 CELLED EGG APPARATUS AT THE

MICROPYLAR END.

3 ANTIPODAL CELL AT THE CHALAZAL

END.

CENTRAL TWO NUCLEI LATER FUSE TO

FORM A SECONDARY NUCLEUS

AFTER POLLINATION

After the landing of pollen grains on the

stigma,

♣Formation and growth of pollen tube take

place –pollen germination

♣Pollen tube grows down through the stigma

and style finally reaches the ovary

♣Enters the ovule

☻ THE FUSION BETWEEN THE MALE GAMETE

AND THE EGG IS CALLED TRUE

FERTILIZATION.

☻AFTER FERTILIZATION

OVULE DEVELOP IN TO SEED

OVARY DEVELOP IN TO FRUIT.

OVARY-FRUIT

OVULE-SEED

FERTILIZATION

• Inside The Ovule Fertilization Is

Takes Place.

• In The Ovule Pollen Tube

Discharges Two Sperms

• One Of The Sperms Fuses With The

Egg And Form Zygote

• Other Fuses With Secondary

Nucleus For Primary Endosperm

Nucleus.