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NYS 4th Grade
Science Review:
How do living things stay alive?
Name: _____________________________________
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Basic Needs of Living Things
People need certain things in order to survive- things like food, water,
clean air, and shelter. Animals, plants, and other organisms have the
very same basic needs. They need to eat, drink and breathe. They
also need shelter from the weather, natural disasters, (such as
hurricanes and floods), and predators. All organisms have special
features called characteristics that help them meet one or more of
their basic needs. Nature doesn’t usually “waste time” giving an
organism a characteristic that doesn’t help it survive in some way. In
this review, you will look at the starting point for life science: the basic
needs of living things.
What is needed to survive?
Animals_________________________________Plants__________
Food
Nutrients
Water
Water
Air
Air
Shelter
Sunlight
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Growth and Survival
Listen to the teacher read about growth and survival. Fill in the notes below.
Word Bank
------------------------------------------------------------------------------------------------------------
characteristics
roots
cells
non-living things
trees
basic needs
living things
nutrients
energy
organisms
change
shelter
If something is to be classified as living, it should have the all
of the following characteristics:
 It is made up of cells.
 It needs food and water.
 It grows.
 It produces itself.
 It responds to change in the place where it lives.
 It gives off wastes.
Animals need shelter in order to thrive. Shelters protect
animals from weather factors such as rain, wind, heat, and
cold. Different animals have different kinds of shelters.
Shelters also protect animals from their enemies.
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Some organisms, such as birds, beavers, and humans
build their own shelters. Beavers build dams and birds build
nests. Some animals dig tunnels into the ground.
Other animals do not have to dig or build their shelter.
Bats and some bears use caves as shelters. Some fish use
underwater plants or coral reefs as shelters. Snakes often live
in holes in the ground left by other animals. Shelters keep
animals warm and safe, but they also give the animals a safe
place to raise offspring.
Plants
Plants have the same basic needs as animals, but they satisfy
these needs in different ways. Animals must consume other
living things like plants, animals, fungi, and so on) for their
food. Plants use sunlight to produce their own food. The
energy in sunlight causes special sugars which the plant uses
for food. Plants “breathe” too: Land plants need clean air and
aquatic (underwater) plants need clean water. Just like
animals, plants need nutrients to grow. Animals get nutrients
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by eating the right balance of different foods. Plants get their
nutrients from the soil by growing roots down into the ground.
Non-living things
Sand, wood and glass are all non-living things. None of these
items show any of the characteristics listed above. Non-living
things can be divided into two groups. First, come those which
were never part of a living thing, such as rocks and plastic.
The second group is those items which were once part of living
things. Coal is a good example. It was formed when trees died
and sank into the soft ground. This happened many millions of
years ago when the Earth was covered with forests. Paper is
non-living but it is also made from trees. Jam is also non-living
but it was made from the fruit of a plant.
Enduring Understandings:
 ALL ORGANISMS HAVE BASIC NEEDS THAT MUST BE MET IN ORDER
TO LIVE AND THRIVE.
 NONLIVING THINGS DO NOT HAVE THESE BASIC NEEDS
 LIVING THINGS NEED AIR, WATER, AND FOOD IN ORDER TO
SURVIVE
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Responding to Change
Listen to the teacher read about how animals and plants change with their environment.
Fill in the notes below.
The Serengeti National Park in Tanzania, Africa, is home to thousands of
different plants and animals. Strangely, though, it’s not a very easy place to live
for all these organisms. In fact, seasons change dramatically every year, going
from severe drought to heavy rains and flooding. The organisms that live there
have developed many curious ways of dealing with these changes. Some
animals migrate long distances during the dry periods to get water, and some
animals bury themselves underground and try to sleep through it! The plants, of
course, don’t have the option of moving to a different place: They’re stuck. But
you’ll see, plants have also developed many ways of dealing with all kinds of
change.
Word Bank
-----------------------------------------------------------------------------------stimuli
internal stimuli
External stimuli
instinct
behavior
Responding to Stimuli
All organisms respond to stimuli. Stimuli are changes that
cause a change in behavior. External stimuli come from the
environment, and internal stimuli come from within the
organism’s body. Animals become thirsty when their bodies
need water, and this internal stimulus causes them to go to find
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a cool drink of water. You have certainly felt that way on a hot
summer day!
Plants do the same thing: As they grow larger, they send
out longer roots to collect more water. Plants can sense water,
as well, almost like an animal can smell food. This helps a
plant grow toward water resources.
Animals gather information about their environments with
their senses, sight, hearing, smell, taste, and touch. Animals
use this information to respond to changes in their
surroundings. For example, the skin responds to changes in
temperature. Some animals perspire, sweat, when they get
hot; others pant, heavy, open-mouth breathing. When it gets
too cold, many animals shiver. This helps keep the animals
warm. As another example, consider how an animal might
respond to a threat. If an animal sees, hears, or smells
something dangerous, its heart might beat faster and its
breathing may speed up. This prepares the animals to move
quickly or react with more strength than usual. You may have
heard of the term “fight or flight”. This is an instinct. When an
animal get scarred, it responds by getting ready to run or put
up a fight.
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You’re probably quite familiar with one internal stimulus:
hunger. Hunger is a message sent by your body to your brain
that says, “Hey, I’m ready for some more energy!” Humans
have figured out many ways to keep a steady supply of food
coming in, and most of us eat three meals a day. As a result,
we don’t feel hunger all the time. Wild animals don’t have it so
easy, however, so they’re almost constantly looking for their
next meal. This is a response to their internal stimulus.
Plants seek out food as well. Their leaves use sunlight to
create sugars and starches. This is the start of almost all the
food energy on Earth.
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Record the information on the T-chart below and highlight external stimuli
in green and internal stimuli in blue.
Internal Stimuli
VS
External Stimuli_____
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