BIOLOGY

Project Report On

POLLINATION
SUBMITTED BY
UNDER THE GUIDANCE OF
N.S.SANTHOSH KUMAR Mrs.
Namrata Saraf
 CERTIFICATE
This is to certify that N.S. Santhosh Kumar , Reg.No. ____________
of Class XII Air Force School Coimbatore has done his project on
POLLINATION under the guidance of Mrs. Namrata Saraf during the academic year
2023-2024 in the partial fulfillment of AISSCE Practical Examination conducted by
CBSE.

Signature of Signature of
Internal Examiner External

Signature of
Principal

Date :
 DECLARATION
I, N.S. Santhosh Kumar , Reg.No._____________ of class XII
Air Force
School Coimbatore hereby declare that the project
entitled
POLLINATION submitted to Mrs. Namrata Saraf during
the Academic
Year 2023-2024 , is a Bonafide record done by myself for
the partial
fulfillment of AISSCE Practical Examination conducted by
CBSE.
 ACKNOWLEDGEMENT
I would like to express my profound gratitude to all those who directly
or indirectly helped me and supported me throughout the project.
Firstly I am highly indebted to my Biology teacher Mrs. Namrata Saraf
for her guidance and constant supervision as well as for providing
necessary information about the project.
I take this opportunity to thank our Principal P. Rajeshwari for providing
me with this wonderful opportunity to work on this project.
I would also like to thank my parents for their endless support and
encouragement throughout the completion of the project’
I also extend my heartfelt thanks to our lab assistant Mrs.Vineetha and
Mrs.Uma for their cooperation and valuable inputs.
 TABLE OF CONTENTS
• SYNOPSIS
• INTRODUCTION
• PROCESS OF POLLINATION
• TYPES OF POLLINATION
• POLLINATING AGENTS
• POLLEN REWARDS
• IMPORTANCE OF POLLINATION
• BIBLIOGRAPHY
 SYNOPSIS
Have you ever wondered why bees are attracted to
flowers? Flowers look beautiful and are fragnant, but
there is a reason behind this – flowers actually help
plants to reproduce. Flowering plants have seeds that
carry the genetic information of the parents and develop
into a new plant.
Explore pollination notes provided here to learn about the
process and types of pollination.
 INTRODUCTION
WHAT IS POLLINATION

Pollination is a method where pollen grains are picked

from an anther, which is the male part of a flower and
transferred to the flower’s female part called the stigma.
To make the pollination work successfully, the pollen
grains must be transferred from the same species of
flower.
PROCESS OF POLLINATION
The process of pollination begins when the pollen grains from the
respective flowers lands on the stigma and form a pollen tube with the
style length, which connects both the stigma and ovary. After the
completion of the pollen tube, the pollen grain starts transmitting
sperm cells from the grain to the ovary.
Later the process of fertilization in plants will take place when the
sperm cells will reach the ovary and egg cells. The seed is then
released from the parent plant and making it able to grow into a plant
and continue the reproductive cycle with the use of the pollination
method.
TYPES OF POLLINATION
• SELF POLLINATION
• CROSS POLLINATION
SELF POLLINATION
It is referred to as the primary type of pollination as it includes a
single flower. Self-pollination occurs when pollen grains fall directly
from anther into the stigma of the flower. This process is quite
simple and fast, which leads to a reduction in genetic diversity as
the sperm and egg cells of the flower share some genetic
information.
 ADVANTAGES OF SELF POLLINATION:

• Self- pollination ensures that recessive characters are eliminated.

• The wastage of the pollen grain is very less compared to cross-
pollination.

DISADVANTAGES OF SELF POLLINATION:

• The vigorous and vitality of the flower is reduced

• The immunity to disease is reduced in the offsprings.
CROSS POLLINATION
It refers to a complex type of pollination that allows the transfer of
pollen grains from the anther of the flower into the stigma of
another flower. This method leads to an increase in genetic
diversity as different flowers will share and combine their genetic
information to create unique offspring.
AGENTS OF CROSS POLLINATION:

• The process of cross-pollination requires the help of

biotic and abiotic agents like animals, birds, wind,
insects, water and other agents as pollinators.
POLLINATION BY WIND-ANEMOPHILY:
• There are only a few flowers that use wind pollination and their features are
greenish, small and odourless flowers. As these flowers do not attract the
pollinators, their energy is not used for making colourful petals. This type of
pollination usually occurs when plants lack flowers with nectar and other features
including inconspicuous. The male parts of the Anemophilous flowers tend to
produce very large quantities of pollen and the stigma, the female reproductive
part of a flower are very large, sticky and feathery to extend completely outside the
flower. Thus the pollen is more likely to reach them.

• Coconut, palm, maize, grasses and all gymnosperms are the best examples of
wind-pollinated plants.
POLLINATION BY ANIMALS- ZOOPHILY:
• Animals play an important role in plant reproduction. They help in
seed dispersal. When an animal eats the fruit of a plant, they move
to a different location. This movement helps in spreading the seeds
and with this, we get new plants to new locations.
ARTIFICIAL POLLINATION-ANTHROPHOPHILY:
• Artificial pollination is done by human beings. This process is also
called as the Anthrophophily. If there are any difficulties in the
pollination process through abiotic or biotic agents, the artificial
method of pollination is performed by spreading pollen grains over
the female flowers. Hybridization techniques are also used in this
process.
ADVANTAGES OF CROSS POLLINATION:
• The produced seed are good in vigorous and vitality.
• All unisexual plants can reproduce through the process of cross-
pollination.

DISADVANTAGES OF CROSS POLLINATION:

• In this process there is a great wastage of pollen grains.
• Due to genetic recombination during meiosis, there are chances of
eliminations of good qualities and additions of unwanted
characteristics in offspring.
Types of Self and Cross-Pollination:
AUTOGAMY:
It is a type of self-pollination where the transfer of pollen grains from the anther to the stigma
takes place within the same flower. Coordinated opening, maturation and exposure of the
anther and stigma are necessary for autogamy. There are two conditions for autogamy to take
place:

Anther-stigma synchronization; when the pollen is released, stigma should be ready to receive
it.
The position of or distance between anther and stigma. Both should be close enough for
pollination.
In chasmogamous flowers, anther and stigma are exposed. The exposed reproductive parts
give a chance of cross-pollination in chasmogamous flowers. While in cleistogamous flowers
anther and stigma are not exposed but lie close enough for transfer. Thus, the chances of
cross-pollination in cleistogamous flowers are almost none. In addition, they barely require a
pollinating agent.
GEITONOGAMY:
Geitonogamy is the type of self-pollination where the
transfer of pollen grains from the anther to the stigma
takes place between different flowers in the same plant.
Though it seems like cross-pollination and takes place
with the help of pollinators, both the gametes have the
same plant as their origin.
XENOGAMY:

• Xenogamy is the cross-pollination where the pollen grain

transfer occurs across flowers of two different plants. In other
words, the transfer of pollen from the anther of one plant to
the stigma of another plant.

• Each type of pollination has its own merits. Xenogamy leads to

a new variety, whereas autogamy helps to preserve parental
characters. Plants have various adaptations to accomplish this
task. In addition, flowers depend on certain pollinating agents
which can either be biotic or abiotic. These biotic and abiotic
pollinating agents are collectively termed pollinators.
POLLEN REWARDS:
• Pollinators are often provided nectar and pollen grains as pollen
rewards.
• In some species floral rewards are in providing safe places to lay
eggs ; an example is that of the tallest flower of AMORPHOPHALLUS.
• A similar relationship exists between a species of moth and the
plant yucca where both species – moth and the plant- cannot
complete their life cycles without each other.
• The moth deposits its eggs in the locule of the ovary and the flower
in turn gets pollinated by the moth.
• The larvae of the moth come out of the eggs as the seed start
developing.
IMPORTANCE OF POLLINATION:
• Virtually all of the world’s seed plants need to be pollinated. This
is just as true for cone-bearing plants, such as pine trees, as for
the more colorful and familiar flowering plants. Pollen, looking like
insignificant yellow dust, bears a plant’s male sex cells and is a
vital link in the reproductive cycle.

• With adequate pollination, wildflowers:

• Reproduce and produce enough seeds for dispersal and

propagation.
• Maintain genetic diversity within a population.
• Develop adequate fruits to entice seed dispersers
BIBLIOGRAPHY:

• www.byjus.com
• www.toppr.com
• www.vedantu.com
• www.subscrid.com