Download How plants grow - Macmillan Caribbean

UNIT 1 LIVING THINGS
How plants grow
Objectives
When you have completed this lesson you will be able to:
• describe how living things grow gradually
• record the germination and growth of different seeds
• arrange pictures of seedlings in order
leaves
Plants are living things.
Living things grow.
stem
bean (seed)
roots
Many plants grow from seeds.
FA S C I NATING
Trees grow slowly all their
lives. The rings in a tree trunk
show how many years
it grew. Each ring is one year.
This tree
was about
70 years
old.
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A bean is a seed. When the conditions
are right, it sprouts. We say that it
germinates.
First roots grow down into the soil.
Then the stem grows up to the light.
Leaves grow from the stem.
Activity
Count the
rings in
this tree.
How old
is it?
UNIT 1 LIVING THINGS
Activity
Investigating the growth of seeds
You will need: different seeds such as
corn (maize), beans, cress and grass,
plastic trays, sheets of paper towel.
Lay paper in the trays and wet it. Put
a different type of seed in each tray.
Put the trays in a dark cupboard or
box. Check the trays every day.
Keep the paper moist.
Draw the seeds as they germinate
and the seedlings grow.
Compare your seedlings.
How are they similar?
How are they different?
Make a display of your observations.
You could measure the seedlings with a
ruler, and plot graphs. A digital camera is
a good way of recording what happens.
KEY WORDS
germinates grow
roots seeds
stem
Check your progress
1.Copy and complete these sentences using some of the key words.
Plants grow from _______________. When conditions are right a seed
_______________. First the roots _______________ down. Then the
_______________ grows up.
2.Put the seedlings below in order.
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UNIT 1 LIVING THINGS
Roots and stems
Objectives
When you have completed this lesson you will be able to:
• state the functions of a plant’s roots
• state the functions of a plant’s stem
The parts of a plant do different jobs.
The roots hold the plant in the soil. They
anchor the plant.
The roots take water from the soil for the
plant.
Activity
Investigating roots
Roots usually keep trees standing
when the wind blows, but they
can’t withstand a hurricane!
You will need: an onion or a hyacinth bulb,
a glass jar with a funnel-shaped neck.
1.Fill the jar to the narrow part with water.
2.Add a few drops of liquid plant food.
3.Place the bulb/onion in the jar so that its
base touches the water.
4.Put the jar on a warm windowsill.
5.Observe it every day. Record what you see.
The roots act like drinking straws and
take up water. The plant needs more water
as it grows, so more roots are produced.
The stem grows up from the ground. It supports
the leaves so they can catch sunlight. The stem
carries water from the roots to the leaves and flowers.
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Water
travels
water
travels
up the
stem
up the
stem
water
The plant’s
roots take
water from
the soil
UNIT 1 LIVING THINGS
Activity
Investigating stems
You will need: some white
flowers, food colouring, jars,
water.
1.Make a clean cut through the flower stems at the base.
2.Add a teaspoon of food colouring to the water in the jars.
3.Stand the flowers in the jars.
4.Leave them in a warm place overnight.
5.Look closely at the flowers. What do you observe?
Water travels through the stems inside hollow
tubes called veins. You can see the coloured
water inside the veins in the flowers’ petals.
KEY WORDS
anchor supports
veins water
Check your progress
1.Copy and complete these sentences using the key words.
A plant’s roots _______________ it in the soil.
A plant’s stem _______________ the branches and leaves.
The roots take _______________
from the soil. Water travels up the
stem through _______________.
2.Fill in the missing labels on this plant.
B
?
Which arrow shows the way water
A
moves through a plant, A or B?
?
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UNIT 1 LIVING THINGS
Branches and leaves
Objectives
When you have completed this lesson you will be able to:
• describe how branches support leaves
• explain that leaves make food for a plant and help it to ‘breathe’
• identify different leaf shapes
As a tree grows, branches grow out from its stem (trunk).
Leaves grow from the branches.
Green leaves are a plant’s food factories. They make
food with the energy of sunlight. To do this they must
face towards the Sun.
Activity
Leaves are sun worshippers!
You will need: a potted plant, a sunny window.
leaves
branch
stem
Stand the plant in the window for several days.
Observe which way the leaves face.
Now turn the plant around so that its leaves face away
from the Sun. Leave it for a few more days. Have the
leaves moved?
Leaves help the plant ‘breathe’ as it grows.
You breathe in and out through your nose and
mouth. A plant breathes through its leaves.
As a plant gets bigger it needs more food
and more air, so it must grow more leaves. It
grows more branches so that the leaves are
spread out, and do not shade each other.
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UNIT 1 LIVING THINGS
You can recognise trees by the shapes of their leaves.
Activity
Looking at leaves
You will need: a paint brush, coloured
poster paints, a pen, sheets of thick paper,
water, newspaper.
1.Make a collection of leaves from
different trees and bushes.
2.Cover a table with newspaper.
3.Place your leaves on the newspaper,
shiny side down. Then paint the
underside of each leaf with a thin coat
of paint.
4.Press the painted side of the leaf
firmly onto the thick paper, then peel
it off to leave a print.
Look carefully at the leaf print. Can you see the
veins? These are the thin tubes that carry water
and food to and from the leaf.
Take leaf prints from different trees. Can you name
them? Use guidebooks to help. Compare the
shapes, sizes and edges of the different leaves.
KEY WORDS
branches breathe
food leaves
Check your progress
1.Copy and complete these sentences using some of the
key words.
A plant grows _______________ to spread its leaves.
A plant’s leaves make _______________. Leaves help
a plant to _______________.
2.Explain why a big plant needs more leaves than a small plant.
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UNIT 1 LIVING THINGS
Looking at flowers
Objectives
When you have completed this lesson you will be able to:
• identify and name some different flowers
• explain that the flowers of some plants become fruits that contain seeds
• collect, preserve and label specimens
Many plants grow beautiful flowers.
Activity
Can you name
these flowers?
What other flowers
do you know?
Brightly coloured flowers with sweet smells attract insects and birds.
Bees and hummingbirds
feed on the sweet nectar
a flower makes.
A powder called pollen sticks to insects and
birds as they visit a flower. Inside another
flower, pollen brushes off. Pollen makes
some flowers change into fruits. The fruits
hold the seeds.
flower
fruit
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FASCINATING
Sunflowers look like the
Sun. They follow the Sun
too. Their heads turn as
the Sun moves
across the sky from
sunrise to sunset.
UNIT 1 LIVING THINGS
Activity
Collecting flowers
You will need: sheets of paper towel, heavy
books, glue, card.
1.Collect some garden flowers (do not take
whole plants – leave the roots and leaves
so that more flowers will grow).
2.Open a large book and lay two sheets of paper towel on it.
3.Arrange the flowers flat on one sheet.
4.Close the book and stack some more books
on it – or use a flower press if you have one.
5.After about four weeks, take out the pressed flowers.
6.Glue your flowers onto card.
7.Label each flower with its name.
The pressed flowers last because they dry out on the
paper towel between the pages of the
book. They do not wilt like fresh
flowers.
You can use pressed flowers
to decorate greetings cards.
KEY WORDS
flowers fruits
nectar pollen
Check your progress
1.Copy and complete these sentences using some of the key words.
Birds and insects visit a plant’s _______________. They carry
_______________ from one flower to another. This makes
some flowers change into _______________.
2.Explain why some flowers are brightly coloured and have a
sweet smell.
3.What do some flowers change into? Why do you think this
is important for the plant?
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UNIT 1 LIVING THINGS
Animals that lay eggs
Objectives
When you have completed this lesson you will be able to:
• classify animals according to whether they do or do not lay eggs
• discuss the numbers of eggs laid by different animals
Animals are living things. Living things
reproduce. They have young that grow
up to be like themselves.
Mammals give birth to live young. A
baby mammal grows inside its mother.
Birds, fish, reptiles, amphibians and insects lay eggs.
A baby hen grows inside an egg outside its mother’s body.
When the chick
is ready, it
breaks out of the
eggshell. We say
that it hatches.
The mother
sits on her
eggs to keep
them warm.
turtle
Activity
Can you match these
eggs to their parents?
How many eggs does
each animal lay – a
few or many?
pelican 18
frog butterfly
UNIT 1 LIVING THINGS
Activity
Hatching eggs
warm water
You will need: a jar of warm water, sea salt, fish
food, brine (salt water) shrimp eggs (from a pet
shop that sells aquarium supplies), magnifying glass.
large jar
(Br
Shrine
imp
s)
brine
shrimp
eggs
(Brine
Shrimps)
1.Stir about 50 grams of salt into 500
sea salt
millilitres of warm water until all the
salt has dissolved. Let the water cool.
fish food
2.Add a little fish food.
3.Sprinkle some brine shrimp eggs onto the
water. Leave the eggs to hatch. This will take
about 2 days.
Look at the water through a magnifying glass.
What can you see?
KEY WORDS
birth egg hatches
lay reproduce
Check your progress
1.Copy and complete these sentences using some of the key words.
Humans and other mammals give _______________ to live young.
Birds, fish, reptiles and many other animals
_______________ eggs.
The baby grows inside the _______________. When it
is ready, it _______________.
2.Say which of these animals lay eggs and which do not.
crocodile goat bee dolphin manatee parrot
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UNIT 1 LIVING THINGS
Animals with bones
Objectives
When you have completed this lesson you will be able to:
• classify animals with backbones as vertebrates
• classify vertebrate animals as mammals, birds, reptiles, fish and amphibians
• list the characteristics of different vertebrate groups
People and many other animals have bones inside their bodies. Bones give
the body shape.
Animals with bones and backbones are called vertebrates. There are five
different groups of vertebrates. These are called mammals, birds, reptiles,
fish and amphibians.
Mammals
Mammals feed their young with milk. They are warm-blooded. Most mammals
have fur or hair on their skin. Their young are born alive.
Birds
Birds have feathers. They are warm-blooded. They lay eggs.
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UNIT 1 LIVING THINGS
Reptiles
Reptiles’ bodies are covered with scales. They are cold-blooded. Most reptiles
lay eggs, though some snakes keep the eggs inside their bodies until they
hatch. The young hatch on land.
Fish
Fish live in water, breathe through
gills and swim with fins. Many fish are
covered with scales. They are coldblooded.
Amphibians
Amphibians are cold-blooded. Their
eggs and young hatch and grow in
water, but the adults can live on land.
FA S C I NATING
The blue whale is the biggest
animal ever. It lives in water
but it is a mammal, not a fish.
It is warm-blooded and feeds
its young with milk.
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UNIT 1 LIVING THINGS
Activity
Classifying animals
Copy this table. List at least three animals in each group. Add more if you can.
Mammals
Birds
Reptiles
Fish
Amphibians
KEY WORDS
amphibians birds
fish mammals
reptiles vertebrates
Check your progress
1.Copy and complete these sentences using some of the key words.
There are five different groups of vertebrates. _______________
and _______________ have warm blood. _______________ and
_______________ have cold blood and lay their eggs in water.
_______________ have cold blood and lay their eggs on land.
2.Which is the odd one out: shark, tuna, dolphin, tilapia? Say why.
3.A turtle lives in the sea, is cold-blooded and lays its eggs on land.
Which animal group does it belong to? Explain your answer.
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UNIT 1 LIVING THINGS
Insects
Objectives
When you have completed this lesson you will be able to:
• distinguish between insects and non-insects
• state the characteristics of insects
Worms, snails, crabs, squid and many other animals do not have bones in their
bodies. The biggest group of animals without bones are the insects. Insects
have a hard skin to give their body shape.
The picture shows the main parts of an
adult insect.
Adult insects have six legs. Their bodies
are divided into three main parts. Many
insects have wings and can fly.
wings
3 body
parts
antenna
eye
This picture shows some of the different kinds of insects.
ladybird
beetle
bee
legs
moth
cricket
dragonfly
fly
ant
mantis
stick insect
butterfly
Activity
Look for insects around your home and school.
Count the number of kinds you see.
Some insects are useful to human beings, but
others harm plants, people and animals – they
are called pests.
flea
FASCINATING
Beetles are insects.
There are at least half a
million different species
of beetle – more than
any other animal group.
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UNIT 1 LIVING THINGS
Activity
Have you seen these insects?
fly
bee
termite
locust
weevil
aphid
mantis
louse
mosquito
cockroach
Say whether each of the insects above is harmful or helpful. Match each insect
to the harm or the good it does (it may do more than one thing).
damages
wooden houses
pollinates
flowers
eats insect
pests
spreads disease
damages crops
makes
honey
lives on our body
KEY WORDS
insects legs
pests wings
Check your progress
1.Copy and complete these sentences using some of the key words.
Adult _______________ have six legs and three main body
parts. Many insects have _______________ and can fly.
Insect _______________ harm plants and animals.
2.Which of these animals are insects? Say how you know.
spider scorpion
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wasp
cricket
UNIT 1 LIVING THINGS
Life cycles
Objectives
When you have completed this lesson you will be able to:
• explain that different animals have different life cycles
• observe the life cycle of a butterfly
• describe the life cycles of an insect and a frog
A new life begins when an animal is born. The animal changes as it grows, and
has babies of its own. These changes are called the animal’s life cycle.
baby
A human baby looks
like a small grown-up.
It gets bigger, but its
shape does not
change very much.
child
(6 years)
13 years
adult
The human life cycle.
Some animals change completely as they grow.
egg
The fly larva (or maggot) hatches
adult
from the egg. It changes into a
pupa. Inside the pupa its body
changes completely to an adult fly.
This is called metamorphosis.
larva
(maggot)
pupa
The life cycle of a fly.
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UNIT 1 LIVING THINGS
In the frog life cycle the
change from a tadpole
to an adult frog is also
called metamorphosis.
adult
egg
Activity
Observing a life cycle
tadpole
The life cycle of a frog.
You will need: a large box, a net, a pot, soil.
1.Collect a plant with butterfly eggs on its leaves.
2.Grow the plant in a pot. Keep the pot in a large box with an open side. Cover
the side with a net.
3.Observe the eggs hatch.
4.Over the following weeks observe what happens. Keep daily records of what
you see.
5.Release the adults back to the wild.
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UNIT 1 LIVING THINGS
Activity
The stages in a butterfly’s life cycle are egg, caterpillar, chrysalis and adult.
Draw these stages in order and add arrows to show the life cycle.
eggs
chrysalis
adult
caterpillar
KEY WORDS
chrysalis larva
life cycle metamorphosis pupa
Check your progress
1.Copy and complete these sentences using some of the key words.
The changes that an animal goes through as it grows up are called its
_____________ ____________.
A caterpillar changes to an adult butterfly by ______________.
This takes place inside a _______________.
2.Write these life-cycle stages in the correct order:
(a)adult fly pupa egg maggot
(b)tadpole adult frog egg
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UNIT 1 LIVING THINGS
Animal habitats
Objectives
When you have completed this lesson you will be able to:
• identify some different habitats and animals that live in them
• describe how animals are adapted to survive in different habitats
The place where an animal lives is its habitat. A dolphin’s habitat is the
ocean. A crocodile’s habitat is the river. A chimpanzee’s habitat is the forest.
There are many different habitats in our world. Deep oceans, hot, dry
deserts, steaming rainforests, snowy mountains — animals live in them all.
Animals’ bodies suit the place where they live. We say that they are
adapted to their habitat. A crocodile has its eyes high on its head so that it
can see above the water.
A polar bear
has thick fur
to keep it
warm in the
ice and snow.
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An elephant’s
big ears help
to keep it cool
in the hot sun.
UNIT 1 LIVING THINGS
Activity
Look at these animals and habitats found in the Caribbean.
1. Match each animal to the habitat in which it lives.
2. Describe ways in which each animal is adapted to its habitat.
clown fish
rainforest
humpback whale
coral reef
howler monkey
seashore
ruddy turnstone
deep sea
FA S C I NATING
Coral reefs and rainforests are two of the richest
wildlife habitats in the world. There are more species
of plants and animals in these habitats than in any
other. Both habitats are found in the Caribbean.
KEY WORDS
adapted
habitat
Check your progress
1.Copy and complete these sentences using the key words.
The kind of place where an animal normally lives is called
its _______________. Animals’ bodies are _______________ to help
them survive in their habitat.
2.Describe how an animal could be adapted to survive in a
cold habitat.
3.Describe how an animal could be adapted to move underwater.
4.Name two different habitats in the Caribbean. List some
animals that live in them.
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UNIT 1 LIVING THINGS
Predators, prey and camouflage
Objectives
When you have completed this lesson you will be able to:
• define the terms predator and prey
• describe how predators and prey use camouflage
An animal that hunts other
animals for food is called
a predator. The animals it
hunts are its prey.
The shark is a fierce
predator. It catches
and eats other
animals in the sea.
FASCINATING
A skunk squirts a
very smelly liquid to
repel a predator. It is
one of the smelliest
animals in the world!
Activity
Predators and prey
Match the predators to their prey in these lists:
Predators:
Prey:
shark
snake
spider
jaguar
fly
tapir
mouse
fish
Predators have adaptations
that help them hunt.
Look at these predators.
Name one adaptation
each has for hunting.
Prey animals have adaptations
to protect them from predators.
Look at these prey animals.
Name one adaptation each
has to protect it from predators.
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scorpion eagle tortoise octopus
porcupine
UNIT 1 LIVING THINGS
Camouflage patterns and colours make an animal difficult to spot in its normal
habitat. Both predators and prey may be camouflaged.
Can you see the predator in this picture? How does
camouflage help it catch its prey?
Can you see the prey in this picture? How does
camouflage help it survive?
Activity
Camouflage test
Spots, stripes and patches of colour
help to disguise an animal’s shape.
But which are best?
Draw animal shapes like these. Colour
them to camouflage them against different
backgrounds – in a tree, on a stone, in the grass.
Which camouflage works best? Hold a competition.
The last animal to be found wins.
KEY WORDS
camouflage
predator prey
Check your progress
1.Copy and complete these sentences using the key words.
A _______________ hunts and eats other animals. The
animals it hunts are its _______________. Patterns and
colours that hide an animal’s body are
called _______________.
2.Name two predators. What are their prey?
3.Why are prey animals often camouflaged?
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UNIT 1 LIVING THINGS
End-of-Unit Test
?
1.Name the parts of this plant.
Say what each part does.
?
2.True or false?
A plant’s leaves make its food. T/F?
Fruits change into flowers. T/F?
When a seed germinates, the root is the first part to grow. T/F?
A plant’s stem anchors it in the soil. T/F?
?
3.Name the odd-one-out in each of these lists. Explain your choice.
Hint – think about how the animals reproduce.
(a) horse, human, hen, hamster
(b) frog, fox, fly, fish
(c) bird, butterfly, bee, bear
(d) mosquito, manatee, mouse, monkey
4.Copy these boxes. Write the names of two animal species in each box.
Add more species if you can.
mammals
birds
reptiles
amphibians
fish
5.(a) Name an insect that is helpful to human beings. Explain how it helps us.
(b) Name two insects that harm human beings. Explain how they
harm us.
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UNIT 1 LIVING THINGS
6.Find the four stages in the life cycle of a butterfly in this word grid.
c
h
r
y
s
a
l
i
s
a
q
a
e
f
d
e
g
t e r p
e g f
a g x
i
l
l
a r
g
u l t
r y
Write the stages in order.
In which stage does metamorphosis take place? What happens?
7.Name some of the different animals that live in each of these habitats.
rainforest
coral reef
seashore
deep sea
8.Select a word from the list below to match each of these definitions.
An animal that hunts other animals. _________
An animal that is hunted. _________
Patterns or colours that disguise an animal. __________
When an animal’s body is suited to the way it lives. _________
adapted
camouflage
predator
prey
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