Transcript Chapter 2

Chapter 2
Energy From Plants
Lesson 1- What are plants’
characteristics?
• Plants are made of small building
blocks called cells.
• Different parts of a cell do different
jobs.
• Plants are multi-celled organisms
made up of tissue and organs.
How plants make food
• Plants need
sunlight and
water in order to
live, grow, and
reproduce.
• They also need
carbon dioxide
from the air and
mineral nutrients
from the ground.
photosynthesis
• Unlike animals, plants
make their own food.
• The food they make is
sugar or glucose.
• The process of making
sugar is called
photosynthesis.
Photosynthesis
• In photosynthesis,
plants use carbon
dioxide that their
leaves absorb from
the air and water that
their roots absorb from
the soil.
*The tubes in the stem carry sugar to
other parts of the plant.
storing glucose
• Three parts of the
plant store the sugar
for the plant.
– Stems
– Roots
– Leaves
Chloroplast
• Photosynthesis
takes place in the
chloroplasts of
leaf cells.
• Chloroplasts
contain
chlorophyll.
Sing this song!!
If you want to know
How a plant grows.
It takes water, air, and sunlight
And makes cellulose
Every plant can do this
Fundamental process
And we can call this
Photosynthesis
Unlike me and you
Plants need CO2
And they make oxygen
That stops us turning blue
CHORUS
It’s a miracle
How all the chlorophyll
Captures sunlight in the leaves
Of the plants and the trees
A plant of any size
Can do it if it tries
But we’re not green,
so we can’t photosynthesize
CHORUS
It’s a miracle
How all the chlorophyll
Captures sunlight in the leaves
Of the plants and the trees
CHORUS
Every plant can do this
Fundamental process
And we can call this
pho-to-syn-the-sis
Photosynthesis
Lesson 2- What are the parts of
plants?
• A plant has different parts. Each part
plays an important role in helping the
plant survive.
• Most plants have three organs,
whether they are a redwood tree or a
dandelion.
– leaves
– stems
– roots
leaves
• All leaves have the same role.
• Their job is to produce food so the plant
can survive in its environment.
• Leaves may be different shapes and sizes
but they all produce food for the plant.
stems
• What does a tree trunk
have in common with the
thin stalk of a dandelion?
• They are both stems and
they have two basic
functions.
– They carry water, minerals,
and food between the roots
and leaves.
– They support the plant,
holding the leaves up so
they can get sunlight.
roots
• The two main jobs of roots are:
– to anchor the plant firmly into the ground.
– take in water and mineral nutrients from
the ground around them.
Roots do
not contain
chlorophyll
Roots grow
away from
the stem in
search of
water and
nutrients.
roots
• Plants can either have taproots or
fibrous roots.
Most trees and grasses have
fibrous roots. In this kind of root
system, the roots spread out in
many different directions.
In taproot systems, there is one
main large root that grows
straight down.
Lesson 3- How do plants
reproduce?
• Scientists classify plants by how they
reproduce (make new plants)
• Flowering plants use parts of the plants to
reproduce.
• There are four main parts to a flowering
plant.
–
–
–
–
Petals
Sepals
Pistil
Stamens
The stamen is the
male part of the
plant. They are
the smaller stalks
around the pistil
The petals are
the parts of the
flower that are
colorful.
The sepals are
the green
leaves below
the petals. They
cover the bud.
Parts of a flower
Anthers are the top
of the stamen
The pistil is the
female part of
the plant.
Reproduction
• Stamens produce the sperm cells.
• The pistil produces the flowers egg
cells.
• They combine to make seeds.
Fertilization
• In order for a seed to
form, pollen has to get
from a stamen to a
pistil.
• The movement of
pollen from the stamen
to the pistil is called
pollination.
• The process of sperm
cells and egg cells
combining is a process
called fertilization.
• After they fertilize, the
egg grows into a seed
and the ovary becomes
a fruit.
Animals play a huge part in the
process of pollination.
Lesson 4- What is the life cycle of
a plant?
• A seed needs the
right conditions to
begin growing.
– It needs 3 things.
• Right amounts of
oxygen
• Water
• Right temperature
Seeds on the move
Animals help scatter seeds.
-Animals eat the fruit on the plant and
digest the seeds…the animals
eventually leaves droppings on the
ground with seeds in them.
- Seeds can catch on animal fur.
- Some animals bury nuts for the winter
and they end up growing into plants.
Wind as a helper
Wind can also help
spread seeds. Have
you ever seen a
dandelion puff
blow in the wind?
Some plants have
“parachutes” that
carry seeds in the
wind.
Some fruits
and seeds
can even be
spread by
floating on
water!
Milkweed plants and
cottonwood trees also have
“parachutes” that carry fruits
and seeds in the breeze.
Starting to grow
• If a seed does not have what it needs
to start growing, it remains dormant (a
state of rest).
• Some plants don’t need seeds to
grow. These plants don’t make flowers
or cones.
– These plants grow from spores, not seeds.
• A spore is a tiny microscopic cell.
Spore Reproduction
• There is a two-step cycle in
the reproduction of spores.
– The plant produces a spore
– A male and female spore
combine and grow into a
plant
• Not all plants grow from
seeds or spores. Some grow
from stems, roots, or leaves.
• Some plants, like
strawberries, grow from
stems called runners.