Why is seed
dispersal
important?
By group SEEDS (10)
P5E
•It
What is seed dispersal?
is the way seeds are dispersed.
•There are many forms of seed dispersal.
•Seed dispersal makes sure that overcrowding does not
happen
•It also enables a species of plant to flourish in various areas.
Methods of seed dispersal.(to be
continued…)
•By gravity > Barochory
•In Barochory, the fruit drops onto the floor
when ripe, dispersing the seeds. (eg. Apples)
•By animals > Zoochory
•In Zoochory, the seeds have hooks to hook
onto animals fur. (eg. Bur) Another kind of
Zoochory is when an animal eats a fruit,
and the seeds get passed out through its
faeces. (eg. Cherries)
More methods of seed dispersal.
•By the wind > Anemochory
•In Anemochory, seeds are light and/or have
wing-like structures. (eg. Dandelion)
•By water > Hydrochory
•In Hydrochory, the fruit, often still with the
seeds inside, have fibrous husks to enable
them to float on water. (eg. Coconut)
Advantages and
disadvantage of dispersal
Advantages and disadvantage of seed
dispersal
Wind

Advantage: It will go further from parent plant and avoid
overcrowding .

Disadvantages: It will reduce the chance of survival for the
seed as if it floats to a place without soil, it cannot
germinate
How wind dispersal works- works when the wind blows
and it carries away the pollen of dome plants.
Some plants like mosses and ferns rely on the wind to help
them
carry their pollen from one place to another.

Dandelions have small wing on their seeds helping to be
easily get carried away by the wind from one place to
another
A video of wind dispersal
Explosive
 Explosive
splitting enables the seed to
be dispersed only around the parent
plant, and not as far as other methods
of dispersal, such as animal dispersal,
of which the seeds can be dispersed
for as many as a few kilometers.
Exploding seed
pod video
Animal
 It
furthers distance traveled by the
seeds, helps avoid inbred-depression
and expands gene pool
 Pollinating animals are attracted to
prominent and colorful flower petals.
 Similarly, modified fruits such as burs
may cling to animal hair, which can
deposit seeds miles away.
Reproduction of plants
Summary
WIND
LIGHT
Feather/wing
like structure
Wings are
twisted and
balanced
Eg. Dandelion..
WATER
WATERPROOF
FIBEROUS HUSK
WHICH HELPS
FLOAT ON WATER
Eg. Coconut,
lotus…
ANIMAL
EXPLOSIVE
MECHANISM
“Hooks”
which
hook onto
the
animal
Dry pods
Undigesta
ble seeds.
Colourful
and
fleshly.(Edi
ble)
Eg.
Apples…
Eg. Balsam…
http://www.you
tube.com/watc
h?v=O6afGgZrn
nA&feature=rel
ated
The story of Rice (rice seed)
Here is an olden myth about rice…
Long ago, in an ancient land, there lived the Rice
tribe. One day ,the locals met a few people in white.
They gave them a few seeds and disappeared. The
awestruck locals planted the seeds, and the next
day, rice plants sprouted. Since then, people all over
the world have eaten rice.
It’s….
TIME!!!
Exciting prizes to be
won!
(Terms and conditions apply)
1. Name 3 plants that disperses its seeds by wind?
Answer> Shorea, lalang, dandelion, angsana (any 3)
2. Briefly explain why seed dispersal is important.
Answer> It prevents over crowding./ It enables the same species
of plants to flourish in different regions.
3. Name the specific name of seed dispersal by gravity.
Answer> Barochory
4. Name the characteristics of seeds that are dispersed by wind.
Answer>Light, wing/feather like structures, twisted and balanced.
Sources…
•www.wikipedia.com
•www.google.com
•www.yahoo.com
•www.youtube.com
!!!!!
Group Members
•Ryan Ng (Leader)
•Xavier Chia (ICT Leader)
•Victoria Tham
•Kalyani S. Anil
Special Thanks
•Mdm Arunah
•Miss Wong
•Members of Temasek Primary’s IT Resource Room
THANK
YOU!!!