Download Asexual Reproduction - Science at St. Dominics

Plant reproduction
Do you remember the 7 characteristics of living things?
1. Movement
2. Respiration
3. Sensitivity
4. Growth
5. Reproduction
6. Excretion
7. Nutrition
Reproduction is the way new individuals are made.
1. Sexual reproduction
Plants can reproduce in two ways
2. Asexual reproduction
What is the difference?
Sexual Reproduction
Asexual
Reproduction
• two parents
• just one parent.
involved.
• 2 different sex
cells join together
to form a zygote.
• the new plant is
NOT identical to its
parents.
• It does not involve
sex cells
• the new plant IS
identical to its
parent.
The following slides show
asexual reproduction…
Day 1
Day 6
Day 13
Day 20
Day 29
Day 42
Day 50
Day 50
Some of the new
growths are beginning
to turn green – these
will become the shoots
of the new plant
Some of the new
growths are beginning
to turn downwards –
these will become the
roots of the new plant
Describe what has happened to this
potato over the 50 days
Other plants that
reproduce asexually….
Asexual Reproduction
•The “runner” grows from
the base of the plant
•when it is at enough
distance it will grow new
roots and a new shoot to
become a new plant.
The strawberry plant
reproduces in this way.
runner
Spider plant
http://www.amherstgreenhouses.com/photo/tropical/spiderPlant.jpg
1. Parent plant
2. Cells divide to
grow a new stem
3. New plant grows
at end of new stem
Strawberry
http://www.bbc.co.uk/schools/gcsebitesize/img/bistrawberries.gif
3. New plant grows at end of stem
1. Parent plant
2. Cells divide to grow new stem
Sexual reproduction
Plants that reproduce sexually use flowers.
Each flower has both male and female organs.
Petals-
Stigma
Style
Stamen
(male)
Anther
Filament
Carpel
(female)
Ovary
Sepals
OB52
…locate the sepal…
sepal
answer
OB52
OB53
OB54
OB55
OB56
OB57
OB58
OB52
…locate the sepal…
sepal
answer
OB52
OB53
OB54
OB55
OB56
OB57
OB58
OB52
…locate the petal...
petal
answer
OB52
OB53
OB54
OB55
OB56
OB57
OB58
OB52
…locate the petal…
petal
answer
OB52
OB53
OB54
OB55
OB56
OB57
OB58
OB52
…locate the carpel…
carpel
answer
OB52
OB53
OB54
OB55
OB56
OB57
OB58
OB52
…locate the carpel…
answer
carpel
OB52
OB53
OB54
OB55
OB56
OB57
OB58
OB52
…locate the stamen…
stamen
answer
OB52
OB53
OB54
OB55
OB56
OB57
OB58
OB52
…locate the stamen…
stamen
answer
OB52
OB53
OB54
OB55
OB56
OB57
OB58
Functions of the stamen – Male
reproductive part
made up of two parts…
•anther: pollen(male sex
cell) is produced here
•filament: this stalk
supports the anther
Making the sex cells…
Functions of the Female parts
…carpel - female reproductive organ…
…made up of three parts…
•stigma: pollen lands here
• style: this stalk connects
the stigma to the ovary…
•ovary: the egg (female sex
cell )is produced here…
During pollination the pollen travels from the
anther of one plant to the stigma of another
plant
Pollen is carried by animals –
insects , bats, birds, dogs etc…
Pollen is also carried by the wind
Fertilisation is when the male gamete joins
with the female gamete, to form the first
cell of the new plant (the zygote)
Making a seed
After fertilisation the first cell divides many times
to make the seed.
‘Bye
Seed dispersal
Dispersal when the seed is brought away from the
parent plant.
• Seeds are dispersed to ensure a better chance of
survival - It avoids overcrowding ! 
Wind dispersal
• Some plants disperse their seeds using the wind.
• An example is the sycamore tree:
Water dispersal
• Some plants disperse their seeds using the wind.
• An example is the coconut plant
Animal dispersal
• Some plants disperse their seeds using animals
• An example is the burdock plant
Self dispersal
• Some plants disperse their seeds themselves
• An example is the pea plant.
The pea fruit bursts open
and throws out its own
seeds
How is this seed dispersed?
How is this seed dispersed?
How is this seed dispersed?
How is this seed dispersed?
How is this seed dispersed?
How is this seed dispersed?
What a seed is made of
Food store
Seed Structure
1. testa 2. food supply
3. embryo = radicle and plumule
this broad bean seed has been soaked and taken apart
…have a closer look at the embryo
…embryo = radicle and plumule…
• the radicle will grow to be the root
• The plumule will grow to be the shoot
Germination
Germination is the growth of the seed into a new
plant
Germination
when the conditions are right, the embryo uses up
the stored food and grows into the root and
shoot of the new plant
…three conditions that must be right
for a seed to germinate…
Oxygen
Water
Correct
temperature
Showing that water, oxygen and the correct
temperature are needed for germination
review the plant life cycle
After fertilization
flower withers
pollen is
transferred
2
3
1
seeds disperse
and germinate
into new plant
4
seeds develop
in ovary