Download BIOLOGY OF PLANTS

1 Biology of Plants Notes BIOLOGY OF PLANTS
Plants are alive, just like people and animals. How do we know this? Living things all
do certain things:
They grow and die.
They need energy, nutrients, air, and water.
They produce young.
They are made up of cells.
They react to what's around them. (Stimuli and
Response)
Plant Parts
What Do Different Plant Parts Do? Plant parts do different things for the plant.
Roots Roots act like straws absorbing water and minerals from the soil. Tiny root hairs stick
out of the root, helping in the absorption. Roots help to anchor the plant in the soil so
it does not fall over. Roots also store extra food for future use.
Stems Stems do many things. They support the plant. They act like the plant's plumbing
system, conducting water and nutrients from the roots and food in the form of
glucose from the leaves to other plant parts. Stems can be herbaceous like the
bendable stem of a daisy or woody like the trunk of an oak tree.
Leaves Most plants' food is made in their leaves. Leaves are designed to capture sunlight
which the plant uses to make food through a process called photosynthesis.
http://www.biology4kids.com/files/plants_photosynthesis.html www.mbgnet.net/bioplants/ 2 Biology of Plants Notes Flowers Flowers are the reproductive part of most plants. Flowers contain pollen and tiny eggs
called ovules. After pollination of the flower and fertilization of the ovule, the ovule
develops into a fruit.
Fruit Fruit provides a covering for seeds. Fruit can be fleshy like an apple or hard like a
nut.
Seeds Seeds contain new plants. Seeds form in fruit.
Two main types of plants are:
(1)Herbaceous:
Plants with stems that are usually soft and bendable. Herbaceous stems die back to the
ground every year.
(2)Woody:
Plants with stems, such as tree trunks, that are hard and do not bend easily. Woody stems
usually don't die back to the ground each year.
Plant processes that help them grow and reproduce.
Photosynthesis:
A process by which a plant produces its food using energy from sunlight, carbon dioxide from
the air, and water and nutrients from the soil.
Pollination:
The movement of pollen from one plant to another. Pollination is necessary for seeds to form
in flowering plants.
What's the difference between a fruit and a vegetable?
A fruit is what a flower becomes after it is pollinated. The seeds for the plant are inside the
fruit.
Vegetables are other plant parts. Carrots are roots. Asparagus stalks are stems. Lettuce is
leaves.
Foods we often call vegetables when cooking are really fruits because they contain seeds
inside.
http://www.biology4kids.com/files/plants_photosynthesis.html www.mbgnet.net/bioplants/ 3 Biology of Plants Notes Plants have adaptations to help them survive (live and grow) in different areas.
Adaptations are special features that allow a plant or animal to live in a particular
place or habitat. These adaptations might make it very difficult for the plant to
survive in a different place. This explains why certain plants are found in one area,
but not in another. For example, you wouldn't see a cactus living in the Arctic. Nor
would you see lots of really tall trees living in grasslands.
Making Food
Plants are very important to us. All food people eat comes directly or indirectly from
plants.
Directly from plants:
Indirectly from plants:
For example, apples come
from an apple tree. The
flour used to make bread
comes from a wheat
plant.
Steak comes from
a cow, and we all
know that cows
are animals, not
plants, right? But
what does the cow
eat? It eats grass
and grains—
PLANTS!
So all the foods we eat come from plants. But what do plants eat? They make their
own food!
What Do Plants Need to Make Food? Plants need several things to make their own food.
They need: 1.
2.
3.
4.
chlorophyll, a green pigment found in the leaves of plants (see the
layer of chlorophyll in the cross-section of a leaf below)
light (either natural sunlight or artificial light, like from a light bulb)
carbon dioxide (CO2)(a gas found in the air; one of the gases people
and animals breathe out when they exhale)
water (which the plant collects through its roots)
http://www.biology4kids.com/files/plants_photosynthesis.html www.mbgnet.net/bioplants/ 4 Biology of Plants Notes 5.
nutrients and minerals (which the plant collects from the soil through its roots)
Plants make food in their leaves. The leaves contain a pigment called chlorophyll, which
colors the leaves green. Chlorophyll can make food the plant can use from carbon
dioxide, water, nutrients, and energy from sunlight. This process is called
photosynthesis.
During the process of photosynthesis, plants release oxygen into the air. People and
animals need oxygen to breathe. This is called Respiration. Sometimes plants lose
liquid through their leaves, stems, flowers, or roots. This process is called
Transpiration.
Photosynthesis – How does it work? Not all of the light from the Sun makes it to the surface of the Earth. Even the light that does make it here is
reflected and spread out. The little light that does make it here is enough for the plants of the world to survive
and go through the process of photosynthesis. Light is actually energy, electromagnetic energy to be exact.
When that energy gets to a green plant, all sorts of reactions can take place to store energy in the form of
sugar molecules.
Remember we said that not all the energy from the Sun makes it to plants? Even when light gets to a plant, the
plant doesn't use all of it. It actually uses only certain colors to make photosynthesis happen. Plants mostly
absorb red and blue wavelengths. When you see a color, it is actually a color that the object does NOT
absorb. In the case of green plants, they do not absorb light from the green range. Chlorophyll is the magic compound that can grab that sunlight and start the whole process. Chlorophyll is
actually quite a varied compound. There are four (4) types: a, b, c, and d. Chlorophyll can also be found in
many microorganisms and even some prokaryotic cells. However, as far as plants are concerned, the
chlorophyll is found in the chloroplasts. The other big molecules are water (H2O), carbon dioxide (CO2), oxygen
(O2) and glucose (C6H12O6). Carbon dioxide and water combine with light to create oxygen and glucose. That
glucose is used in various forms by every creature on the planet. Animal cells require oxygen to survive.
Animal cells need an aerobic environment (one with oxygen). So what do you need to remember? 1. Plants are producers that can make or produce their own food. 2. Plants take in the gas carbon dixoide (CO2) and water (H2O). 3. Plants have a unique compound called chlorophyll that helps plants produce their own food. 4. Plants grab the sunlight (energy) and use chlorophyll to convert water (H2O) and carbon dioxide (CO2) and make oxygen (O2) and glucose (C6H12O6). http://www.biology4kids.com/files/plants_photosynthesis.html www.mbgnet.net/bioplants/ 5 Biology of Plants Notes 5. So the glucose or (C6H12O6) plants make is just a fancy way of saying sugar, and that provide energy or
food for the plant to grow and complete all its life processes. 6. Then the plant releases the excess molecules of oxygen (O2), which in turn helps us to complete our
respiration (breathing) process. What gas do we need to breath in? 7. That’s right, we then breathe in the oxygen (O2) that the plants have released and then we release
carbon dioxide (CO2) back into the air, which is exactly reverse of the plant. The plants will then use
the (CO2) we release and continue their process of photosynthesis. 8. Do plants and people depend on each other? Absolutely. Not just for food, because we eat plants, but
also for the air that we breathe! Stimulus – A change in the external or internal world that causes a response. Response – How an organism reacts to a stimulus. Turgor Pressure -­‐ is the main pressure of the cell contents against the cell wall in plant cells and bacteria cells, determined by the water content of the vacuole, resulting from osmotic pressure. This force gives the plant rigidity, and keeps it upright. http://www.biology4kids.com/files/plants_photosynthesis.html www.mbgnet.net/bioplants/ 6 Biology of Plants Notes ] http://www.biology4kids.com/files/plants_photosynthesis.html www.mbgnet.net/bioplants/