Transcript PLANT GROWTH ADAPTATIONS

PLANT PARTS AND
ADAPTATIONS
Mrs. Herrema
2012
Water Lilies
note the shape and size of the leaf. The water lily
grows in a shaded area.
Water Lilies
• Water-lilies are rooted in soil in bodies of
water, with leaves and flowers floating on
the water surface. The leaves are round,
large and flat to absorb as much of the
sunlight as possible. The lily uses the
sunlight to make food.
Water Lilies
Cacti are distinctive and
unusual plants which
have adapted to extreme
arid environments. Their
features conserve water.
Their stems have
expanded into green
structures containing the
chlorophyll necessary for
life and growth, while the
leaves have become
the spines for which
cacti are so well known.
Compare the size of the
leaf on a cacti that sits
in the sun to the water
lily that is in the shade.
All living organism need nitrogen. Plants make
proteins from nitrogen in the soil. Animals get the
nitrogen they need to make proteins when they eat
plants.
In the nitrogen cycle, nitrogen is
changed into forms of nitrogen that
plants can use.
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The forms are:
Nitrates
And
Ammonia
• They are returned to
the soil in two ways:
• Through animal
wastes.
• When plants and
animals die, a
bacteria releases
nitrates and ammonia
from decaying
proteins.
Carbon Dioxide-Oxygen Cycle
• In the carbon dioxide-oxygen cycle, all
land and marine organisms take in oxygen
and release carbon dioxide as a product of
turning food into energy.
For millions years the carbon dioxide-oxygen cycle
stayed in balance because of the processes of
plants and animals.
• Now we burn trees and coal which puts tons of carbon
dioxide into the air.
• Burning fuels such as natural gas and petroleum in cars,
trucks and airplanes, add even more carbon dioxide to
the air.
• We cut down forests to use for human needs. So there
are fewer trees to use the added carbon dioxide.
• Carbon dioxide is poisonous to animals and
humans
What are three things we can do to
help keep the carbon dioxideoxygen cycle in balance?
• 1.
• 2.
• 3.
What do Plants need to live?
One of the main
Materials used to
Water
Make food.
Nutrients
Basic Needs
Of
Plants
Air
Carbon Dioxide
Help plants
grow.
Light
Provides the
Energy for
photosynthesis
One of the main
Materials used
To make food.
Parts of a vascular plant
How do leaves, stems, and roots
help plants live?
•
ROOTS
• Roots absorb NUTRIENTS and WATER through tiny parts called
root hairs. Roots anchor the plant in the soil, provide support for
the stem, and store food. They are usually below ground and lack
nodes, shoots and leaves.
•
ROOT TYPES
• There are two major types of root systems in plants.
• Taproot systems have a stout main root with a limited
number of side-branching roots. Examples of taproot
system plants are nut trees, carrots, radishes, parsnips
and dandelions.
• The second type of root system, fibrous, has many
branched roots. Examples of fibrous root plants are most
grasses, marigolds and beans.
Fibrous roots and a tap root
Some plants store extra food and water to help them
survive brief changes in their environments. Most
plants cannot make food during the winter.
Prop roots
• Some tree
roots, called
prop roots,
keep trees that
grow in loose,
wet soil, from
being blown
over by the
wind.
• STEMS
• The stem is the main trunk of a plant. Buds and
shoots develop on stems. Stems provide
structure and support for leaves, flowers and
fruits. They also carry nutrients and water. In
some cases, stems also store food.
• The xylem and phloem are located in the
stem. They are found only in vascular
plants.
http://www.goldiesroom.org/Shock
wave_Pages/052-Pressure%20Flow%20Model%201.
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How water and nutrients flow
through the xylem and phloem
The xylem fills with material to
become the “wood” of the tree.
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LEAVES
• Leaves are lateral outgrowths from the stem. The main function of
leaves is food production for the plant.
• Leaves have evolved into many shapes and sizes, reflecting
adaptations to the environment. Leaves are most commonly
flat, broad and green. This maximizes their function of
absorbing sunlight and transforming it into food.
•
Leaves have a protective layer on the outer surface of their cells
called the cuticle (Q-tick-uhl). This protective layer reduces the
exchange of water and gases and prevents some disease-causing
organisms from entering. The cuticle is made up of a waxy
substance called cutin (Q-tin). The cuticle helps prevent
DEHYDRATION.
Transpiration
• For leaves to release and take in gases
(carbon dioxide, oxygen) and water vapor,
the leaf surface has tiny openings called
STOMATA (stow-MAH-tah).
• Guard cells surround the stomata and
push it open and closed.
Stomata is used for transpiration
Tropisms are a plant’s responses
to stimuli that help a plant survive.
Gravitropism is the
plants response to
gravity. This
makes sure the
plants roots grow
downward.
Just think what would happen when seeds are planted
upside down.
Phototropism
Plants grow toward
light. This response
to light is called
phototropism.
Plants have the
ability to measure
the amount of
sunlight they need.
Just think what would happen if plants could not move their
leaves toward the sun.
Other Tropisms
This plant
responds to
the stimulus of
touch.
As you can see, Responses to stimuli are
adaptations that help plants survive.
Parts of a leaf