fertilization in plants
description
Transcript of fertilization in plants
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.