Plants Science 4º - WordPress.com · 3/4/2020 · Science 4º As you know, plants are classified...
Transcript of Plants Science 4º - WordPress.com · 3/4/2020 · Science 4º As you know, plants are classified...
Science 4º
Plants are all around us. They are living things because they do the three life processes: nutrition,
interaction and reproduction. Plants are very important for us because they give us they oxygen that
we need to live and clean the enviroment of pollution.
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Plants
There are many different types of plants
which we can classify in different ways.
Grasses Bushes Trees
They have a soft
stem and they
are thin, flexible
and short.
They have a
thick and hard
stem with low
branches.
They have one thick
and hard stem called
trunk. They are tall
and with high
branches.
Trees can be differents. There are deciduous trees (they change their
leaves in autumm) and evergreen trees (they change their leaves all year
round).
Science 4º
We can also classify plants by how they reproduce. There are flowering plants and
non-flowering plants.
Plants
There are two subgroups:
Angiosperms: They produce big and colorful flowers which will turn
into fruit with seeds inside. For example: roses, apple trees or blackberry
bushes.
Gymnosperms: They produce small flowers and don’t produce fruit.
Their seeds develop inside cones. For example: evergreen trees like the
pine.
In this group we find mosses and ferns. They don’t produce seeds, they
produce tiny spores which they release into the air.
Flowering plants
Non-flowering plants
Leaves
Branch
Trunk
Soil
Roots
Parts of
a tree
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Science 4º
How plants make their own food? They make their food by photosynthesis and they need:
Water + minerals + light and energy from the Sun + carbon dioxide
Plants
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During the process of photoshyntesis,
plants release oxygen into the air.
PHOTOSYNTHESISEnergy and light
from the Sun
Carbon dioxide
WaterMinerals
The roots absorb water and
minerals from the soil.
The water and minerals travel
up the stem to the leaves.
The leaves make the food in this process
called photosynthesis where the plant
absorbs carbon dioxide through their leaves.
The carbon dioxide combines with water,
minerals and sunlight to make food.
Remember this ecuation!
Water + minerals + light and energy from the Sun + carbon dioxide = Food + oxygen
Oxygen
Science 4º
Plants, as living things, need to breathe. During their breathing process plants absorb
oxygen and expulses carbon dioxide but, as you know, during the day they do the
photosynthesis, so they produce oxygen too. But only during the day!
Plants
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respiration
Photosynthesis
Oxygen
Carbon dioxide
Respiration
Carbon dioxide
Oxygen
Respiration
Oxygen
Carbon dioxide
Carbon dioxide
Oxygen
Carbon dioxide
Oxygen
During the day At nigth
Science 4º
As you know, plants are classified as flowering plants and non-flowering plants.
In this part, we going to learn how flowering plants reproduce.
Plants
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Flowering plants use their flowers to reproduce because inside the flowers are the reproductive organs.
These reproductive organs make the seeds that grow into the new plants.
Animal pollination Wind pollination
Stigma
Stamens
Petals
Sepals
Ovary
They produce
pollen.
They recive the pollen
from other flower to
the ovary.
It grows into a fruit
which has seeds inside.
They are small
green leaves that
protect the flower
before it opens.
They can be many
different colours and
attract insects to the
flower.
Insects and birds that feed with nectar
transfer the pollen of the flower from the
stamen to the stigma of another plant.
It is when wind blows the pollen from
one plant to another.
In this page, you can see how a flowering plan reproduces.
Science 4ºPlants
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Pollen from other flower lands
on the stigma and travels down.
A seed develops inside the
ovary.
The ovary takes the form of
a fruit and the petals fall.
The fruit grows and falls. When
it is on the ground, it opens and
lets the seeds go out.
The seed germinates and
a new plant grows.
The new plant produces
flowers and the cycle starts
again.
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