Download How Do Plants Get Food

How Do Plants
Get Food?
by Barbara J. Davis
Science and Curriculum Consultant: Debra Voege, M.A.,
Science Curriculum Resource Teacher
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Science in the Real World: How Do Plants Get Food? Copyright © 2010 by Infobase Publishing
All rights reserved. No part of this book may be reproduced or utilized in any form or by any means,
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Library of Congress Cataloging-in-Publication Data
Davis, Barbara J., 1952
How do plants get food? / by Barbara J. Davis; science and curriculum consultant, Debra Voege.
p. cm. — (Science in the real world)
Includes index.
ISBN 978-1-60413-468-1
1. Photosynthesis—Juvenile literature. I. Title. II. Series.
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Index by Nila Glikin
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Table of Contents
Food and Life............................................................ 4
Food Factory............................................................. 6
Plant Parts: Roots and Stems.................................. 8
Plant Parts: Leaves................................................. 10
The Food-Making Process . ................................... 12
Plants That Steal.................................................... 14
Animal-Eating Plants.............................................. 16
Plants and Ecosystems........................................... 18
Producers and Consumers.................................... 20
Food Chains............................................................ 22
Food Webs.............................................................. 24
Energy Pyramids.................................................... 26
Helping Plants Help People.................................. 28
Glossary.................................................................. 30
To Learn More........................................................ 31
Index....................................................................... 32
Words that are defined in the Glossary are in bold type
the first time they appear in the text.
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Food and
Life
Squirrels eat the nuts
and seeds of trees and
other plants.
T
hink about the last time you were
at a park. How many different
types of living things did you see?
Perhaps you sat on the grass and
watched an ant crawl over your
hand. You might have seen squirrels
running along a tree branch. Maybe
birds flew overhead. What you might
not realize is that you and all the
other living things you saw have
something in common. Every living
thing needs food to survive.
Living things are
called organisms.
Food provides the
materials that all
organisms must
have to grow and to
be healthy. There
are many sources of
food in the world.
Animal Food and
Plant Food
Some animals get
food by eating other
animals. Some
birds eat worms
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and insects. Other animals get food by
eating plants. The squirrels in the park
might have been
looking for acorns
ready to fall from the
tree. (Acorns are
the nuts made by
oak trees.) For almost
all animals, getting
food is usually a
matter of eating
another organism.
But plants are
different. For almost
all plants, getting
food does not mean
eating another
organism. Most
plants can make
their own food.
DID YOU KNOW
?
Plant Facts
Have you ever wondered how many types of plants there are in the
world? Scientists believe there are more than 270,000 different kinds of
plants. The water duckweed plant is the smallest plant that has flowers
or makes fruit. Water duckweed is less than a thousandth of an inch long
(less than 0.001 inches, or 25 micrometers). Giant sequoia trees (see
photo above) are among the largest plants in the world. Some grow to
385 feet (117 meters) tall.
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Food
Factory
A
factory is a place where a
product is made. A plant is
something like a factory. The
product of a plant factory is food
for the plant.
To understand how a plant
factory works, you need to know
a little about the smallest part of
any plant—the cell. Some plants
have only a few cells. Other plants,
though, have many millions of cells.
Plant cells are so small they can be
seen only with a microscope. Each
plant cell has certain parts that have
special jobs to do.
The Parts of a Plant Cell
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Plant cells have a special structure
around them called a cell wall. This
wall is strong. It provides support
and protection for the cell.
The cell membrane is like a thin
inner wall next to the stronger cell
wall. The cell membrane’s main job is
to allow needed water and nutrients
into the plant cell.
Within the cell is the nucleus.
The nucleus guides most of the cell’s
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Parts of a Plant Cell
activities. It’s
Mitochondria
Cell Wall
Cell
almost like the
Membrane
brain of the cell.
Cytoplasm
Vacuoles
There are
Nucleus
other structures
inside a plant cell.
Chloroplasts
Vacuoles are sacs
that store water
and other materials
Each part of a plant
cell has a special job.
that the plant cell needs. The mitochondria
The chloroplasts hold
are structures in the cell where energy for
chlorophyll, which
the cell is stored for later use.
the plant needs to
make food.
Many, but not all, plant cells have green,
oval-shaped parts called chloroplasts.
Chloroplasts have a green material that is
called chlorophyll. A plant cell must have
chlorophyll in order to make food for
the plant.
The cytoplasm is a jelly-like material
that is mainly water. The nucleus, vacuoles,
mitochondria, and chloroplasts lie in the
cytoplasm.
DID YOU KNOW
?
Grass Stains
If you have ever rolled around in the grass, you probably got green
streaks on your clothes. Those streaks are chlorophyll. The weight of your
body crushes the grass leaves and the cells that make up the leaves. The
liquid-like chlorophyll that leaks out of the crushed cells is easily absorbed
by clothing, leaving what people call “grass stains.”
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Plant Parts:
Roots and
Stems
Three important parts of
many types of plants are
the roots, the stem, and
the leaves.
A
ll plant cells have the same
basic parts. However, certain
types of cells can specialize—that is,
they do a certain type of job for the
plant. Some cells will have the job of
helping the plant stay upright. Other
cells will specialize in making food.
Specialized plant cells form the
main structures in a group of plants
called vascular plants. These are
plants that have vessels, or tubes,
that carry water and other materials
throughout the plant.
Many common plants are vascular
plants, including trees, bushes, and
most flowering plants.
Parts of a Plant
Leaves
Stem
Roots
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Below and Above the Ground
A vascular plant’s roots are usually
underneath the ground. The roots have two
main jobs. One job is to hold the plant in
the soil. The soil is the source of the water
the plant needs to make food. There are also
nutrients in the soil that the plant needs to
stay healthy. The other job of
the roots is to actually absorb
water and nutrients from
the soil. Tubes in the roots
carry the absorbed water
and nutrients to the stem.
Stems usually grow above
the ground and support the
plant. They also allow the
leaves of the plant to reach
sunlight, so that the plant can
make food. Like roots, the
stems of vascular plants carry
water and nutrients to other
parts of the plant.
DID YOU KNOW
Root Snacks
?
A taproot is a strong root that reaches deep into the soil. Besides absorbing water and nutrients, some taproots also store food for the plant. This
makes these particular taproots a good healthful food for people, too.
Carrots, beets, radishes, and sweet potatoes are all examples of taproots.
The photo here shows some carrots just pulled out of the ground.
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Plant Parts:
Leaves
Most leaves have different
layers. One of the layers has
cells with chloroplasts for
making food.
T
he leaves of a plant have one
main job—to make food for
the plant. Most leaves have several
layers of cells. Each layer has a
special job.
The outer layer is called the
epidermis. The epidermis on the
side of the leaf that faces up usually
has a coating of wax to help keep
water in the leaf. The underside of
the leaf, or the lower epidermis, has
small openings called stomata. The
stomata open and close at different
times during the day and night. When
the stomata are open, they allow
Inside a Leaf
Upper Epidermis
with Waxy
Coating
Cells with
Chloroplasts
That Make
Food
Cells That
Hold Water
and Other
Materials
Vein
Lower
Epidermis
Stomata
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carbon dioxide into the leaf. Carbon dioxide
is a gas that is found in the air. It is one of
the materials the leaf needs to make food.
Sometimes the stomata close. This helps keep
water in the leaf.
Where the Food Is Made
A layer of cells that have chloroplasts is found
just below the upper epidermis of the leaf.
Most of the food-making in the leaf takes place
in this layer. Remember that the chloroplasts
have chlorophyll. Along with water, light, and
carbon dioxide, a plant cell must have chlorophyll to make food.
A spongy layer of cells just above the lower
epidermis has spaces that hold the basic
materials, like water, that the plant will need
to make its food. The leaf surface also has a
series of veins. These veins connect to the
tubes in the stem that bring up water and
nutrients from the soil.
DID YOU KNOW
?
Nonvascular Plants
Nonvascular plants are plants without tubes. They rely on other means
to carry water and food throughout the plant. Instead of roots, nonvascular plants have very fine root-like parts that hold them to soil. These
plants are usually small and low to the ground. Water and nutrients are
absorbed directly into leaf-like parts of the plant, like a sponge. The food
made in the leaf-like parts moves from cell to cell within the plant. Moss is
an example of a nonvascular plant.
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The FoodMaking
Process
P
In photosynthesis, a plant
uses sunlight, water,
carbon dioxide, and its own
chlorophyll to make its food.
lants make their own food
through a process called
photosynthesis. Photosynthesis
begins when light strikes the plant’s
leaves. The chlorophyll in the
chloroplasts captures energy from
sunlight. This starts a chemical
change that makes the water in the
leaf split into its two basic parts.
These parts are the gases oxygen
and hydrogen. The oxygen (which
is not needed by the plant) goes out
of the plant through the leaves and
enters the air.
How Photosynthesis Works
Sunlight strikes
the chlorophyll
in the chloroplasts
Oxygen goes
out of the leaf
into the air
Carbon
dioxide from
the air enters
the leaf
Water is carried up
from the roots
In the chloroplasts, sunlight splits the
water into hydrogen and oxygen, and the
hydrogen combines with carbon dioxide
to make sugar, which is the plant’s food
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Sugar for Food
Carbon dioxide enters the leaf through the
stomata. In a series of steps, the carbon
dioxide combines with the hydrogen to create
a type of sugar called glucose. This sugar is
the plant’s food. It gives the plant the energy
it needs to grow and stay healthy. Glucose
is also in the white sugar you may use on
your cereal. White sugar is also called “table
sugar.” It is a combination of glucose and
another type of sugar called fructose.
In a plant, some of the sugar stays in the
leaves. Some is moved through the tubes in
the plant to the cells in the stem. The stem
cells keep some of the sugar, and the rest is
carried down to the cells of the roots. If the
plant has fruit, some sugar goes there, too.
The plant uses some of the sugar it makes
right away. The rest is changed into a form
of energy that is stored in the plant cells’
mitochondria. This energy can be used
later when the plant needs it.
DID YOU KNOW
?
Fresh Air
Plants are putting oxygen into the air as part of photosynthesis. People
and other animals breathe in oxygen. When they exhale, or breathe out,
they put carbon dioxide into the air. Carbon dioxide is just what plants
need for their photosynthesis. This is just one of the many ways in which
plants and other living things depend upon each other for life.
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Plants That
Steal
A
ll green plants can make
their own food through
photosynthesis. These plants have
chloroplasts and chlorophyll, which
are the things that make the plant
green. Some plants don’t have a lot
of chloroplasts and chlorophyll.
They can make some of their food
but not enough to survive. These
plants use other means to add to
their food supply.
Mistletoe is a plant that has light
green leaves and white berries. It attaches itself to certain types of trees,
such as oak or pine trees. Mistletoe
can make some of its food from
The witches’ hair plant
gets all of its food
from the bush or tree
it attaches itself to.
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photosynthesis. It takes the rest of the water
and nutrients that it needs from the tree. It
is one of a group of plants called parasites. A
parasite plant attaches itself to another plant
and “steals” water or other nutrients.
Living Completely Off Other Plants
Some parasite plants, like mistletoe, make
some of their own food. Other parasite
plants, like witches’ hair, or dodder, have no
chloroplasts at all. They cannot make any of
their own food. These plants live entirely by
taking food from other
plants. Witches’ hair is
common in California.
It looks like long orange
strings, and it wraps
itself around the stems
of bushes or trees and
takes water and nutrients from the stems.
DID YOU KNOW
?
The Corpse Flower
The corpse flower, which grows in the Asian country of Indonesia, is the
world’s largest flower (see photo above). One type can grow as large as
3 feet (almost 1 meter) across. The corpse flower is also a parasite. It
cannot make its own food and depends totally on the vine it attaches
itself to in order to live. The corpse flower gets its name because it gives
off an odor like rotting flesh.
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AnimalEating
Plants
A Venus flytrap leaf can
close to trap an insect
and turn it into a meal
for the plant.
S
ome plants that cannot make all
of their own food don’t get the
rest by stealing from other plants.
They get it by trapping animals.
These “meat-eating” plants are called
carnivorous plants. Scientists have
identified more than 600 different
types of carnivorous plants around
the world.
Some carnivorous plants have
colorful tubes that tempt insects into
the plant. Once inside, the insect is
trapped by sticky material inside the
tubes. Then, a special
fluid dissolves the
insect and turns it
into the plant’s food.
There are carnivorous
plants that look quite
ordinary, with a pretty
flower on a stalk.
However, the stalk
has fine hairs coated
with sticky material
that trap insects that
land. Again, a special
fluid then dissolves
the insects.
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Venus Flytrap
The Venus flytrap is a well-known
carnivorous plant. This plant has green
parts and can make some of its own food.
The rest of what it needs it gets from
trapping flies. The leaves of a Venus flytrap
open wide, like a mouth. There are short,
stiff hairs surrounding the leaf. When an
insect touches one of these hairs, it
signals the leaf
to close. The
trapped insect
cannot get out,
and it is slowly
dissolved by
special juices
in the leaf.
This bladderwort
has trapped its prey.
DID YOU KNOW
?
Fast Food
Bladderworts are carnivorous plants that can be found all over the world.
They get their name because the plants have little bags, or bladders,
hanging from them. Bladderworts live mainly in areas where there is a lot
of water. The plant’s bladders are underground in very wet soil or in the
water of rivers and lakes. The bladders act as traps for their prey, which
can be anything from tiny insects to larger worms. The bladder has a type
of trap door. When the prey bumps up against it, the door opens and
water rushes in, carrying the prey with it. This happens in much less than
a second! Inside, special juices do the work of dissolving the prey.
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Plants and
Ecosystems
This frog about to take a swim
is part of a pond ecosystem.
A
ll the world’s plants live in some
type of ecosystem. An ecosystem is formed by all the living
and nonliving things in an area. An
ecosystem’s living things include
plants and animals. Nonliving things
include air, water, and soil. The world
is made up of many different types of
ecosystems.
An ecosystem can be as small as
a puddle of water. You would need
a microscope to see the very tiny
plants and animals living there. A
pond ecosystem might include plants
like cattails and water lilies. This
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ecosystem would
also have flying
insects, such as
mosquitoes, as well
as frogs and fish.
There would also
likely be birds and
raccoons living
around the pond.
Life in the Desert
It might be hard to think of a desert as an
ecosystem with living things—deserts can be
so dry and hot, and they can seem so barren.
In fact, desert ecosystems often have a wide
variety of plants and animals. Desert plants
may include cactus and bushes that grow low
to the ground. Desert animals such as lizards,
jackrabbits, and roadrunners may live among
the plants. Large desert spiders may also call
the ecosystem home.
The tortoise and the
Mojave desertrue
shrub it was using
for some shade are
both part of a desert
ecosystem.
DID YOU KNOW
?
Different but the Same
Even though ecosystems can be very different, they all have one thing in
common. An ecosystem’s plants and animals depend on each other to
survive. The living things within an ecosystem need energy for every part
of life. In most cases, that energy will first come from the plants that are
living there.
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Producers
and
Consumers
These deer get the energy
they need to live from the
grass they eat.
A
ll ecosystems have living things
called producers. The word
“produce” means make. Most plants
are producers because they make
their own food through photosynthesis. Some of the food the plant makes
is stored in the plant. Later, the plant
can use this stored food to get the
energy it needs to live, grow, and
make more food.
A plant’s stored food is like stored
energy. Other living things can also
get and use the plant’s stored energy.
They can do this by eating the plant.
Living things that eat other living
things are called consumers. Eat is
one meaning of the word “consume.”
Animals are one type of consumer
because they eat plants or other
animals to get
the energy they
need to live.
Some animals
like cows or
deer eat only
plants. When
these animals
eat grass, they
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are getting some of the energy stored in the
blades of grass. Animals like wolves and lions
eat other animals. They get the energy to live
from the animals they eat.
What Are Decomposers?
Decomposers are a special type of consumer.
Bacteria, fungi, and earthworms are all decomposers. Bacteria eat the remains of dead
plants and animals. Fungi and earthworms
consume the remains of dead plants. These
decomposers break down the remains into
nutrients. They use
some of the nutrients, and other
nutrients go back
into the soil. This
is helpful to plants.
Plants use these
nutrients when they
are taken up by the
plants’ roots.
DID YOU KNOW
?
Are Mushrooms Plants?
Many people believe that mushrooms are plants. They aren’t. Mushrooms
are actually fungi. They are also decomposers. Like other fungi, mushrooms do not have chloroplasts in their cells. Without chloroplasts, the
mushroom cannot make its own food. Instead, it breaks down the remains
of dead plants into nutrients.
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Food Chains
F
ood energy in an ecosystem is
passed from one living thing to
another. A food chain describes a
single path through which that food
energy is passed.
The process is called a “chain”
because each organism in the chain
is linked, or joined, to another
organism. The plants and animals
are linked by the way food energy is
being passed from one to another.
The organisms depend on one
another to live.
All food chains begin with a
producer plant. Let’s say a food
chain begins with a carrot plant.
Remember that the root of this plant
is a plump carrot storing food made
by the plant.
First, the carrot is eaten by a
consumer—a rabbit. When that happens, some of the food energy from
the carrot is passed to the rabbit.
Moving up the Chain
In most ecosystems, the first consumer is probably eaten by another
consumer. Perhaps a fox catches
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A Food Chain
This food chain starts
the rabbit and eats it. The fox gets food enwith a producer
ergy from the rabbit. Sometimes, still another
plant—a carrot—and
ends with a
consumer is part of the food chain. Maybe a
mountain lion.
mountain lion eats the fox. As with every other
part of the chain, the mountain lion gets
some food energy from the fox.
DID YOU KNOW
?
Producers in the Dark
No sunlight makes it to the bottom of the ocean. This means that plants
can’t grow there. The bottom of the deep ocean is full of living things,
though. How can this be without a plant to begin the food chain? There
may not be plants, but there are producers. These are a certain kind of
bacteria that use a chemical that comes out of cracks on the sea floor.
The bacteria combine the chemical with water and carbon dioxide to
make types of sugar. These sugars are in the bacteria’s bodies. The
bacteria become food for another organism, and the food chain begins.
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Food Webs
M
ost ecosystems have several—
or even many—food chains.
These food chains are connected to
each other.
A food web is all of the connected, or linked, food chains in an
ecosystem. A food chain shows one
path through which food energy
is passed from one living thing to
another. A food web shows a number
of possible food energy paths.
Chains Form a Web
Most animals eat more than one type
of food. For example, the rabbit that
ate the carrot may also eat grass
seeds. Birds also eat grass seeds.
The grass is part of more than one
food chain.
The same fox that ate the rabbit
might also eat the bird. The fox may
also eat a chipmunk that eats acorns.
The fox is part of several different
food chains.
The mountain lion that ate the fox
might also eat a rabbit. An owl might
also be in this food web, eating the
chipmunk, for example.
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A Food Web
This food web has
Food webs exist in the sea. The
many different pathproducers in most ocean food webs are
ways in which food
energy travels from
tiny organisms called phytoplankton. They
one living thing to
make food through photosynthesis. Algae
another.
are phytoplankton. Other living things called
zooplankton eat the phytoplankton. Small fish
eat zooplankton. Larger fish eat smaller
fish and also eat zooplankton. Sharks may
eat larger fish and also smaller fish. Sea birds
that eat fish are also part of the food web.
DID YOU KNOW
?
A World of Food Webs
Food webs exist wherever there are things that eat other things. Whether
the ecosystem is an ocean, a desert, a pond, or a forest, food webs exist.
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Energy
Pyramids
A food energy pyramid needs
to have many producer plants
at the bottom to support the
animals that are consumers.
A
n energy pyramid shows how
much actual food energy is
passed along at each stage of the
food chain. A plant uses most of
the food energy it makes to live and
grow. Only the food energy stored to
be used later can move to another
living thing if the plant is eaten. Only
about 10 percent of the food energy
made by the carrot plant gets to the
rabbit that eats the carrot.
The rabbit also uses most of the
energy it gets to live and grow. Only
A Food Energy Pyramid
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about 10 percent of the food energy the rabbit
takes in is passed on to the fox that eats the
rabbit. This low rate of energy transfer
continues all the way up the food chain.
Consumers at the Top
The consumer at the top of
the energy pyramid has to
eat many other living things
to get enough food energy to
live. This is why most food
chains have only three or
four levels. The producers
at the bottom of the energy
pyramid support the energy
needs of all the levels above
them. If there are too many
top-level consumers, there
would have to be a huge
number of producers to
support them.
DID YOU KNOW
?
Where People Fit into the Energy Pyramid
You have a choice of where you fit into an energy pyramid. When you bite
into a juicy hamburger, you are what is called a second-level consumer.
You get your food energy from an animal (a cow) that ate plants (grass).
When you eat vegetables, you are a first-level consumer. You get your
food energy directly from the plants that made it.
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Helping
Plants Help
People
An acre of land planted with
wheat can provide more
food than the same amount
of land when it is used to
feed cows that are raised
for food.
T
he ability of plants to make food
is important for almost all living
things. Plants are usually the first
level in any food chain. There are
many things that people do, though,
that harm the ecosystems where
plants grow or that use up too
many plants. There are also some
things that people can do to help
use resources more efficiently.
Eating More Foods from Plants
One is to eat more vegetables, fruits,
and foods made from wheat and
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other grains. The beef
people eat comes from
cows that need to eat a
lot of grass. If someone
ate only meat, that person
would need the meat from
about ten cows each year.
Ten cows need about 5
acres (2 hectares) of grass
a year. If someone ate only
food made from grains,
just 1 acre (0.4 hectares)
of wheat would provide
enough food for a year.
Of course, people don’t
eat only beef or only food
made from wheat. But the
more a person eats foods
from plants, the less land that is
needed to grow that person’s food.
This model shows what a
vertical farm building in a
city might look like.
DID YOU KNOW
?
The Vertical Farm Project
Some experts believe that, by the year 2050, the world may have more
than 9 billion people. (It has fewer than 7 billion now.) Some scientists
are concerned that there may not be enough farmland to feed this larger
population. One scientist’s answer to this problem is called the Vertical
Farm Project. The idea is to put up specially designed tall buildings in
which food plants can be grown. The buildings can be in cities, and the
food can help feed the world’s growing number of people.
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Glossary
bacteria—Types of tiny livings
thing that have one cell.
carnivorous—Meat-eating.
cell membrane—A thin, flexible
sheet of material that surrounds
the inside of a cell.
cell wall—The strong outermost
layer of a plant cell that gives it
support.
chlorophyll—A green-colored
material inside some plant cells
that captures energy from sunlight
that is used in photosynthesis.
chloroplast—A structure inside
some plant cells that holds the
plant’s chlorophyll.
cytoplasm—A jelly-like material
inside a cell in which the nucleus
and other parts of the cell are found.
decomposer—A living thing that
breaks down dead plants or animals
into nutrients and other materials.
ecosystem—An area in which a
group of plants and animals live that
depend on one another for survival.
food chain—A pathway by which
food energy is passed directly from
one living thing to another.
food web—A group of interconnected food chains.
fungi—Types of living things that live
by taking nutrients from dead plants.
glucose—A type of sugar. It is the
type produced in plants during
the process of photosynthesis.
grains—Plants such as wheat, corn,
and rice that are major sources of
food energy.
mitochondria—Structures in cells
where food energy is stored for later
use.
nucleus—A structure inside a cell
that controls the activities of the cell.
nutrients—Substances that give a
living thing the materials it needs to
grow and be healthy.
organism—A living thing.
parasite—A living thing that lives
on or in another living thing and gets
what it needs to live from that other
living thing.
photosynthesis—The process by
which a plant makes its own food.
stomata—Tiny openings in the outer
layer of a plant leaf.
vacuoles—Sacs inside a cell that
hold water and other things the cell
needs.
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To Learn More
Read these books:
Kalman, Bobbie. Photosynthesis: Changing Sunlight into Food. New York:
Crabtree Publishing, 2005.
Latham, Donna. Respiration and Photosynthesis. Chicago: Raintree Publishing,
2009.
Pollock, Steve. Ecology. New York: Dorling Kindersley, 2005.
Look up these Web sites:
Brain Pop—Our Fragile Environment
http://www.brainpop.com/science/ourfragileenvironment
Environmental Literacy Council
http://www.enviroliteracy.org/students-index.php
Full-Time Exploring Science and Technology—Photosynthesis
http://www.ftexploring.com/photosyn/photosynth.html
Science News for Kids—Plants
http://www.sciencenewsforkids.org/pages/search.asp?catid=26
Key Internet search terms:
ecosystems, food chains, photosynthesis, plants
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Index
Air 12, 13, 18
Animal-eating plants 16–17
Animals 18–19, 20–21, 22–23, 24–25,
26–27
Bacteria 21, 23
Birds 4, 19, 24, 25
Bladderworts 17
Carbon dioxide 11, 13
Carnivorous plants see Animal-eating
plants
Cell structure in plants 6–7
Chloroplasts and chlorophyll 7, 10, 11, 14
Corpse flower 15
Cytoplasm 7
Decomposers 21
Desert 19
Ecosystems 18–19
Energy storing and transfer 7, 19, 20, 23,
24, 26–27
Epidermis (leaf) 10
Fish 25
Food chains and food webs 22–25
Fruits and vegetables 28
Fungi 21
Grains 28–29
Hydrogen 12, 13
Insects 16–17
Leaves 8, 10–11
Making of plant food 7, 10–11, 12–13
Mistletoe 14
Mitochondria 7, 12
Mushrooms 21
Nonvascular plants 11
Nucleus (plant cells) 6–7
Number of plants 5
Ocean 23, 25
Oxygen 12, 13
Parasite plants 14–15
Parts of plants 8–9, 10–11
Photosynthesis 12–13, 25
Phytoplankton 25
Roots (plants) 8–9
Soil 9, 11, 18
Squirrels 4, 5
Stems (plants) 8–9
Stomata 10
Sugar 13, 23
Sunlight 9, 12, 23
Taproot 9
Trees 5, 8, 14
Vacuoles 7
Vascular plants 8–9
Venus flytrap 17
Vertical Farm Project 29
Water 9, 11, 12, 15, 17, 18
Zooplankton 25
About the Author
Barbara J. Davis has written books on science topics for kids
for more than fifteen years. She has published books on
ecosystems and biomes, as well as on earth science subjects.
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