Grade by Grade
B. Life Systems ยท Needs and Characteristics of Living Things

What Living Things Need

B2.2 A1.2 A1.5About 35 minutes
Learning goals
  • I can name the basic needs of living things: air, water, food, heat, shelter and space.
  • I can tell how plants, animals and people meet their needs.
  • I can do a fair test to find out what a plant needs.

Words to know

need
Something a living thing must have to stay alive and healthy.
want
Something that is nice to have but you can live without, like a new toy.
shelter
A safe place that protects a living thing from weather and danger, like a house, a nest or a den.
space
Enough room to move, grow and find food.
heat
Warmth. Living things need the right amount of warmth to stay alive.
fair test
An experiment where you change only one thing so you can see what that one thing does.

A new puppy!

Your family brings home a new puppy. What will the puppy need to stay alive and healthy?

It will need food in a bowl, fresh water, air to breathe, a warm bed inside, and room to run and play. You will need to take care of it every day!

A golden puppy sitting in a soft dog bed next to a bowl of food and a bowl of water.
This puppy has food, water and a warm place to rest. These help meet its basic needs. AI-generated image

The six basic needs

All living things have basic needs. A need is something they must have to stay alive. Living things need:

NeedWhyExample
๐ŸŒฌ๏ธ airto breathe (plants use air too)A whale swims up to breathe air.
๐Ÿ’ง waterto drink and to growA dog drinks from its bowl. Rain waters a garden.
๐ŸŽ foodto get energy and to growA rabbit eats clover. Plants make their own food using sunlight.
๐Ÿ”ฅ heat (warmth)to stay the right temperatureWe wear snowsuits in winter. Seeds need warm soil to sprout.
๐Ÿ  shelterto stay safe from weather and dangerA beaver lives in a lodge. A bear sleeps in a den.
โ†”๏ธ spaceroom to move, grow and find foodCarrots planted too close together grow small.
The six basic needs of living things
Living thingsneed...airto breathewaterto drink, growfoodfor energyheatto stay warmshelterto stay safespaceroom to grow
All living things have the same six basic needs. If even one is missing, a living thing cannot stay healthy.

Plants have needs too

Plants do not eat food like we do. Plants make their own food in their leaves, using sunlight, air and water.

So a plant needs sunlight, water, air, the right warmth, and space to grow. Most plants also grow in soil, which holds them up and gives them some of what they need.

Needs and wants

A need is something you must have to live: food, water, air, warmth, shelter, space.

A want is something nice but you can live without it, like a video game, candy or a new bike.

Ask: "Could I stay alive and healthy without it?" If yes, it is a want.

Worked example

Let's find the needs of a Canada goose

How does a Canada goose meet its basic needs?

  1. Air: It breathes air with its lungs, like we do.
  2. Water: It drinks from ponds and lakes, and swims in them.
  3. Food: It eats grass, seeds and water plants.
  4. Heat: Its feathers keep it warm. Many geese fly south to warmer places in the fall.
  5. Shelter: It makes a nest on the ground near water to keep its eggs safe.
  6. Space: It needs open land and water to find food and fly.

The goose meets all six needs: air, water, food, heat, shelter and space.

Just for fun

What if plants could order dinner? They'd say: "One sunshine, a glass of water and some fresh air, please. Hold the pizza!"

That's because plants make their own food.

Worked example

Let's plan a fair test

Do plants need water? Let's plan a fair test.

  1. Question: Do bean plants need water to grow?
  2. Plan: Use 2 cups with the same soil and the same kind of bean plant. Put them in the same sunny window.
  3. Change only one thing: Cup A gets water every few days. Cup B gets no water.
  4. Predict: What do you think will happen? (I think Cup B will droop.)
  5. Observe every day for 1 to 2 weeks. Draw pictures of both plants.

Cup A keeps growing. Cup B droops and dries up. Our test shows that plants need water. It is fair because water was the only thing we changed.

Bag A: dampBag B: dryDay 1Day 5sprouted roots!no change
A fair test: both bags are the same except for water. Only the damp beans sprout, so seeds need water to start growing.
Hands-on activity

Seed experiment: water or no water

You need: 4 dry beans (from the grocery store), 2 clear plastic bags or jars, paper towels, water, tape, and a grown-up.

  1. Fold a paper towel and put it in each bag. Put 2 beans in each bag.
  2. Make Bag A damp (wet but not soaking). Leave Bag B dry.
  3. Tape both bags to a sunny window, side by side. Everything is the same except the water!
  4. Predict: Which beans will sprout?
  5. Look every day for a week. Draw what you see and write the day.
  6. Talk about it: What happened? What does this tell us about what seeds need to grow?

What to look for: The damp beans should split and grow little roots in 2 to 5 days. The dry beans stay the same. Seeds need water (and warmth) to start growing.

Safety: Do not eat raw beans. Wash your hands after.

Your turn

1

Name the 6 basic needs of living things.

2

How does a plant get its food?

3

Need or want: a warm coat in January?

4

Need or want: a chocolate bar?

5

What is a beaver's shelter called?

6

Why do tomato plants need space in a garden?

More practice: warm-up

1

What do you breathe?

2

Does a cat need water?

3

Name one kind of shelter for people.

4

Need or want: a video game?

5

What does a plant need from the sun?

More practice: on your own

1

A goldfish lives in a bowl. How does a person help it meet its needs?

2

Why does a bear sleep in a den in winter?

3

Ella forgot to water her plant for 2 weeks. What will she probably see? Why?

4

In our fair test, why did we put both bean bags in the same window?

5

Which basic need does a snowsuit help you meet?

Challenge

1

Pick an animal that lives near you. Tell how it meets each of its 6 needs.

2

Leo wants to test if plants need light. He puts one plant in a sunny window and one in a dark closet. He waters only the window plant. Is this a fair test? Why or why not?

3

Plants do not eat food. So why do we say all living things need food?

Check your understanding

Quiz

1.

Which is a basic need of living things?

2.

How do plants get food?

3.

A bird's nest is a kind of...

4.

Which is a want, not a need?

5.

In a fair test, how many things should you change?

6.

Carrot seeds were planted very close together. The carrots grew tiny. What need was missing?

For parents and teachers

Big idea: All living things (plants, animals and people) need air, water, food, heat (warmth), shelter and space. Plants make their own food using sunlight.

Common difficulties:

  • Mixing up needs and wants. Ask "Could you stay alive and healthy without it?"
  • Thinking plants need "plant food" from a bottle to eat. Fertilizer helps plants grow, but plants make their own food in their leaves using sunlight, air and water.
  • Changing more than one thing in an experiment. The bean experiment is a fair test because only water changes. Ask "What is the same? What is different?"

How to help: Do the bean experiment together and keep a simple picture diary. When you shop, ask "Is this a need or a want?" This lesson uses the scientific experimentation process (A1.2) and recording results with drawings (A1.5).