t5 – life cycles · seeds will germinate and grow into new plants. plants can die at any stage of...

Natural Sciences and Technology: Grade 5 – Term 1 – Topic 5 (Life cycles) – Brain chart Copyright @ www.summariessa.co.za

Nearly all the flowering plants

began their life as little seeds.

Seeds grow into seedlings and into

adult plants when the conditions

are right.

Adults plants grows flowers.

Flowers can be pollinated and

turns into fruit with seeds in them.

Seeds will germinate and grow into

new plants.

Plants can die at any stage of the

life cycle, it can be eaten, or it can

die because they do not get

enough nutrients, water or air.

Pollination and fertilisation are

important in a plant’s life cycle.

Plants do not start off their lives

with all their parts. – they are

constantly growing new parts

throughout their lives.

Petals – attracts birds and insects to flower.

Stigma – sticky female part that catches pollen. Pollen then grows a tiny tube (pollen tube)

into the ovary of the flower

Anther – male part that makes pollen. Pollen needs to get to the stigma. Insects, birds and

wind help to carry the pollen from flower to flower.

Style – supports the stigma and leads to the ovary.

Filament – supports the anther.

Ovary – stores ova that will become seeds if fertilised. After fertilisation it grow and

becomes a fruit. Seeds inside the fruit are dispersed by wind, water, animals and birds.

Sepals – protect the flower when it is a bud.

All living things need to reproduce which ensure that that

they do not become extinct or die out.

An animal can die at any point of its life cycle.

Sometimes they get very old and their bodies no longer

work properly.

Animals are either born alive or they hatch from eggs.

Animals are born with all their limbs.

Life cycle of a cow:

o Bull places his sperm inside the cow (cow and bull mate). When a

sperm cell joins an egg, fertilisation takes place.

o Fertilised egg (embryo) grows inside the cow (cow is pregnant).

Embryo becomes a baby inside the cow’s body.

o After 285 days the baby is ready to leave the cow and the cow

gives birth to the calf.

o Cow cares for the calf. Cow keeps it warm, protects it and gives it

milk.

Animals need a partner to reproduce. Father – male partner

and produces sperm. Mother – female partner and makes

eggs inside body.

Fertilisation is when the sperm and eggs join.

Internal fertilisation – when the male partner puts it sperm

inside the body of the female partner. E.g. all mammals, birds,

snakes, lizards, tortoises, insects and spiders

External fertilisation – Eggs are fertilised outside the body.

Fish and frogs – mother lays eggs, father spreads his sperm

over the eggs.

Mammals – embryo develops inside the mother’s body. Body

provides the embryo with everything it needs to develop; most

mammals gives birth to live young. Parents keeps their young

warm, feed and protect them.

Birds and reptiles lay eggs – they do not give birth to live young.

Embryo develops inside the egg which has a hard, protective

shell. Birds sit on the nest until the eggs hatch. Young gets cared

for by parent. Lizards hide their eggs but does not stay with the

eggs.

Mammals feed their young on milk, protects them and

train them to survive.

Dogs keep their puppies close to them, monkeys cling on

to its mother stomach for the first few weeks. Mother

bird leaves the nest only to search for food. Piglets needs

their mother to keep them warm the first two weeks.

Frogs, insects, fish and turtles bury or hide the eggs, but

do not stay close after they are born.

T5 – Life cycles

Life cycle of a plant

Pollination of a plant

Life cycle of an animal

Animal reproduction

Fertilisation

Pregnancy and growth Caring for the young

Topic 5: Life cycles

GR5 NST T1-T5 Summaries 1

5555.1: .1: .1: .1: Growth and developmentGrowth and developmentGrowth and developmentGrowth and development ((((PgPgPgPg.48.48.48.48----57)57)57)57)

Key concepts:

The following stages occur in the life cycle of a plant: germination;

growth of taproot; plant matures and makes its own food;

pollination; fertilisation; fruit ripens; seeds are dispersed.

If the seeds germinate, the cycle starts again.

The following stages occur in the life cycle of a mammal:

fertilisation; female is pregnant; female gives birth; young animal

grows; animal becomes mature.

If the mature animals reproduce, the cycle starts again.

Death can take place at any stage of the life cycle.

Key words:

Life cycle Stages through which a living thing

passes during its lifetime.

Pollination When pollen from the male parts of a

flower reaches the female parts

of the flower.

Germinate

Begin to sprout or grow into a

seedling.



Fertilisation When male cells in pollen join eggs

in the female parts of a flower to

form seeds.

Reproduce When plants and animals produce

offspring.

Extinct When all the individuals of a type of

plant or animal die and no more are

left.

Internal

fertilisation

Joining of male cells and female egg

inside the body.

External

fertilisation

Joining of male cells and female eggs

outside the body.

Sequence The order in which something

happen.



All living things have a life cycle.

A cycle is a set of steps that happen one after the other. When the last step is

reached, the cycle goes back to the first step and starts all over again.

A life cycle is in the shape of a circle. It shows the repeating pattern of life for

all living things.

Every living thing has its own life cycle.

When a baby animal starts to

develop, it almost immediately

begins to grow all its body parts

that it will need throughout its life.

By the time the baby animal is

born or hatches from an egg, it has

all its body parts.

From the moment of birth on, the

animal just grows bigger and more

mature.

Plants do not start their lives with all their parts. They are constantly growing

new parts throughout their lives.



Life cycle of a plantLife cycle of a plantLife cycle of a plantLife cycle of a plant

Nearly all the flowering plants began their life as little seeds.

When the conditions are right, seeds grow into seedlings.

Seedling eventually grows into adult plants.

Adult plants grow flowers.

After the flowers have been pollinated, they can turn into fruit with seeds in

them.

These seeds will germinate in soil and grow into new plants. In this way, the

cycle of life continues.

This is shown in Figure 2 on page 49 of your textbook.

The plant can die at any stage of the life cycle.

For example: the plant itself may be eaten by buck or giraffe, or the seeds may

be eaten by birds. Plants can also die because they do not get enough

nutrients, water or air.



Pollination and fertilisationPollination and fertilisationPollination and fertilisationPollination and fertilisation

Pollination and fertilisation are important steps in a plant’s life cycle.

For seeds to form, pollination must first take place.

Pollination happens as follows:

o Petals – attracts birds and insects to the flower.

o Stigma - sticky female part that catches pollen. The pollen then grows a

tiny tube, known as the pollen tube, into the ovary of the flower.

o Anther – male part that makes pollen. Pollen needs to get to the stigma.

Insects, birds and wind help to carry the pollen from flower to flower.

o Style – supports the stigma and leads to the ovary.

o Filament – supports the anther.

o Ovary – stores ova that will become seeds if fertilised. After fertilisation

the ovary of the flower grows and becomes a fruit. The seeds inside the

fruit are dispersed by wind, water, animals and birds. The seeds can grow

into new plants.

o Sepals – protect the flower when it is bud.

Stigma

Anther

Style

Filament

Ovary

Sepals

Petals



Life cycle of an animalLife cycle of an animalLife cycle of an animalLife cycle of an animal

All living things need to reproduce – they need to make more living things like

themselves.

A plant or animal can die at any point in its life cycle. Animals can die because

they become ill or are hunted.

Sometimes they get very old and their bodies no longer work properly.

Reproduction makes sure that different kind of living things do not become

extinct or die out.

Animal reproductionAnimal reproductionAnimal reproductionAnimal reproduction

Animals go through different stages of development and have a life cycle.

The life cycle of an animal shows all the stages it goes through from the time it

is born until it dies.

Animals are either born alive from their mother or they hatch from eggs. They

then grow and mature into adults.

A mammal is a vertebrate, which is a warm-blooded animal with a backbone.

Although a cow can live up to twenty years and then die of old age, it can, like all

other animals die at any time during its life cycle from illness or perhaps an accident.

The life cycle of a cow (see Figure 6 on page 52 of your textbook)

o The bull places his sperm inside the cow. We say that the cow and the bull

mate. When a sperm cell joins an egg, fertilisation takes place.

o The fertilised egg is called an embryo. It grows inside the cow. We say the

cow is pregnant. The embryo becomes a baby inside the cow’s body.

o After 285 days, the baby is ready to leave the cow’s body. The cow gives

birth. We call the baby a calf.

o The cow cares for the calf. She feeds the calf milk. She keeps the calf

warm and protects it. The calf learns from the cow.

o The calf grows into a mature bull or cow. This takes three to four years. The

adult bull or cow can mate with a partner to reproduce. The cycle starts again.



Fertilisation Fertilisation Fertilisation Fertilisation

Most animals need a partner to be able to reproduce.

The father is the male partner and his body produces sperm.

The mother is the female partner and she makes eggs inside her body.

The sperm and the egg must join to form a new life. This is called fertilisation.

Internal fertilisation:

o When the male partner puts his sperm inside the body of a female partner.

o All mammals such as cows, humans, elephants and cats reproduce in the

same way.

o The same thing happens with birds and reptiles such as snakes, lizards and

tortoises.

o Other animals that live on land, such as insects and spiders, also use internal

fertilisation.

External fertilisation:

o When eggs are fertilised outside the mother’s body.

o The mother lays the eggs in water and the father spreads his sperm over

the eggs.

o Fish and frogs use external fertilisation.



Pregnancy and growth Pregnancy and growth Pregnancy and growth Pregnancy and growth

In mammals, the embryo develops

inside the mother’s body. While the

mother is pregnant, her body

provides the embryo with

everything it needs to develop.

Most mammals give birth to live

young.

Parents keep their young warm,

feed and protect them.

The young will grow into adults and

will be able to have babies of their

own.

Birds and reptiles lay eggs. They

do not give birth to live young.

The embryo develops inside an

egg.

Eggs are covered by a hard,

protective shell.

Birds lay eggs in nests. They sit on

the nest until the eggs hatch.

Parent birds care for their young

until they are ready to leave the

nest.

Female lizards lay eggs. They hide the eggs. The young lizards hatch from the

eggs.



Caring for the young Caring for the young Caring for the young Caring for the young

Many animals care for their young to make sure

they grow and develop into mature animals able

to produce babies of their own.

New-born mammals are often weak and

defenceless. Some, like horses, can stand on

their own feet and run within an hour of being

born.

Mammals feed their young on milk, so the young stay close to their mother. In

this way, their mothers not only feed them, but also protect them.

Parents train young animals how to survive.

When the young are mature enough, they leave

their mother to face the world on their own.

Dogs take care of their young the same way that a

human takes care of her baby. The mother is very

protective of her puppies and will keep them close

to her. She feeds and cleans them until they are old

enough to be weaned and until she knows there is

another source of food for them.

A monkey will often spend its first few weeks of life clinging on to its mother’s

stomach. This is the start of a very close bond with their mothers.

A mother bird never leaves her chicks unless she is searching for food. Then,

the father takes over watching them until she

returns.

Piglets needs their mother to keep them warm

for the first two weeks of their lives. Piglets feed

from their mothers about four times a day.

Not all animals care for their young in this way.

Frogs, insects, fish and turtles are some of the

animals that bury or hide their eggs to keep them

safe, but they do not stay close to their young after they are born.



ActivityActivityActivityActivity 1111: : : : Find out what you already know about the life cycles of plants Find out what you already know about the life cycles of plants Find out what you already know about the life cycles of plants Find out what you already know about the life cycles of plants

and animalsand animalsand animalsand animals ((((P 47P 47P 47P 47))))

Briefly describe what pictures A and B in your workbook are about.

Picture A displays the different growth stages of a bean plant. Picture B displays

an adult fly laying eggs, which will eventually develop into young flies.

1. Describe one difference in the way plants and animals grow and develop.

Plants produce their own food to grow. Animals must eat. Plants keep on

growing throughout their lives. Animals grow and stop growing as they

reach adolescence. Animals are born with all their body parts while plants

develop as they grow.

2. In picture A, you can see a bean plant. List three foods that contain seeds.

Examples: Tomato, cucumber, apple, pumpkin, butter squash.

3. If seeds are planted and watered, what may happen?

A plant can grow.

4. In picture B, little white eggs can be seen. Think of two animals that lay

eggs.

Birds, fish

5. Why do some animals lay eggs?

The animals' little ones develop in the egg. The egg provides nutrients and

is a form of protection for the embryo before birth.



ActivityActivityActivityActivity 2222: : : : Identify the phases in the life cycle of an avocado tree Identify the phases in the life cycle of an avocado tree Identify the phases in the life cycle of an avocado tree Identify the phases in the life cycle of an avocado tree ((((PPPP 55551111))))

1. Match the labels to the correct pictures numbered 1 to 5, on p.51 in your

textbook:

Avocado trees can start producing fruit in 10 to 15 years.

Avocado seeds germinate four to six weeks after planting.

Yellow flowers grow on the adult tree.

The young plant is known as a seedling.

The seedling grows into a healthy adult plant.

1.1 Avocado seeds germinate 4-6 weeks after planting.

1.2 A young plant is known as a seedling.

1.3 The seedling grows until it is a healthy adult plant.

1.4 Yellow flowers grow on the tree.

1.5 An avocado tree can begin bearing fruit after 10 to 15 years. They can

bear fruit for over 50 years.

2. Write down one sentence to explain the following terms:

a. Germinate

A seed germinates as it starts to grow and changes into a seedling.

b. Taproot

A root is the first root to appear when the seed starts to sprout.

c. Mature

An adult plant is a mature plant.

d. Pollination

Pollination occurs when the pollen of the male part of a flower joins

the female parts.

e. Fertilisation

If the male cells in the pollen connect with the eggs in the female parts

of a flower, fertilization occurs.

f. Seed

A seed comes from inside a fruit of a plant and can grow into a new

plant.



ActivityActivityActivityActivity 3333:::: Identify, draw and label the male and female parts of a flower Identify, draw and label the male and female parts of a flower Identify, draw and label the male and female parts of a flower Identify, draw and label the male and female parts of a flower

((((PPPP 51)51)51)51)

* Read the activity and see below.

Step 1:

From the outside, we first notice the petals.

The petals make the flower attractive to birds and insects, forming a

protective band around the softer inner parts.

Step 2:

When we carefully remove the petals from the flower we can see the two

main parts of the flower - the stamen and the pistil.

The stamen is the male part of the flower.

It forms a ring around the female part of the flower, called the fruit leaf or

the pistil.

The stamen consists of

o A "head" - the anther

o a tube - the filament.

The anther produces male seed - pollen.

Step 3:

The pistil or fruit leaf consists of the stigma, style and ovary.

The stigma is the sticky female part of the fruit leaf. It catches the pollen and

from there a pollen tube grows along the style to the ovary.

In the ovary, small eggs called ova (plural) or an ovum (singular).

The pollen joins with the ovum and it is called fertilisation.

Step 4:

When we gently open the ovary with a pin, we see the ova (small eggs).



Step 5:

Fertilisation develops a brand-new seed from the male and female parts of

two different plants.

The seed is a complete plant that will grow when it receives water, heat and

nutrients from the soil.

Step 6:

The calyx consists of small, green sepals.

It encloses the bud (immature flower) and holds the petals of the flower

together.

It also provides protection to the ovary.



ActivityActivityActivityActivity 4444: : : : Revise the life cycle of a mammalRevise the life cycle of a mammalRevise the life cycle of a mammalRevise the life cycle of a mammal ((((PPPP 55)55)55)55)

Read through pages 51 to 54 again.

1. The flow diagram in Figure 11 shows the life cycle of a mammal. Redraw this

diagram in your workbook. Then close this book and fill in the empty boxes.

2. Write one sentence to explain each of the following:

a. Fertilisation c. Birth

b. Pregnant d. Hatch

a. When the male sperm and the female egg fuse to form a new life, it is called

fertilization.

b. When a female mammal has a fertilized egg in her, the fertilized egg becomes

an embryo and we say the animal is pregnant.

c. The process in which a developed baby comes out of his mother is called birth.

d. When a chick comes from an egg, it hatches.

Fertilisation takes place

inside the mother's body

Baby leaves the mother's

body

The young mammal

learns from his parents

and grow

The young animal

grows and becomes an

adult animal

Adult animals can pair

to make more animals



3. The sentence below describes the stages in the life cycle of a cat. They are in

the wrong order. Write them in the correct order.

The kittens grow until they are mature.

The female cat is pregnant for 65 days.

The female cat feeds her kittens with milk.

The male and female cats mate and fertilisation takes place inside the

female’s body.

The mature cat can reproduce, and the cycle starts again.

The female cat gives birth to her kittens.

Right order:

The male and female cats mate and fertilisation takes place inside the

female’s body.

The female cat is pregnant for 65 days.

The female cat gives birth to her kittens.

The female cat feeds her kittens with milk.

The kittens grow until they are mature.

The mature cat can reproduce, and the cycle starts again.



ActivityActivityActivityActivity 5: 5: 5: 5: NNNName, label and sequence stages in plant and animal life cyclesame, label and sequence stages in plant and animal life cyclesame, label and sequence stages in plant and animal life cyclesame, label and sequence stages in plant and animal life cycles

((((PPPP 56565656))))

Part 1: plant life cycles

1. Look at the six photographs on page 56, A to F, showing the different stages in

the life cycle of a pumpkin. The photographs are not in the correct order.

a. Write down the letters of the photographs in the correct sequence.

b. Label each stage in the life cycle of a pumpkin next to its correct letter (A –

F). Choose the correct answer from the stages given below.

c. Write a sentence next to each label to describe what happens at that stage in

the life cycle of a pumpkin.

Vine Seeds Flower Green pumpkin Seedling Ripe pumpkin

Label Description

D Seed Take up water and germinate

C Seedling Seeds emerge and grow into a seedling

A Vine The roots and stems of the plant begin to grow and

begin to make their own food.

B Flower Pollination occurs when the male part of the flower

joins the female parts.

E Green pumpkin When male cells in the pollen connect with the eggs in

the female parts of the flower, fertilization occurs and

flowers turn into fruit like the pumpkin.

F Ripe pumpkin The fruit becomes ripe with seed inside which can in

turn become mature plants.



2. Look at the diagram of the life cycle of a plant in figure 12.

A-B Draw the life cycle in your workbook. Give the drawing a suitable

heading.

C Name the process which occurs when a seed begins grow roots and

leaves.

Germination

D Describe the difference between a seed and a seedling.

A seedling is a seed that has sprouted or started to grow. A seed is

covered with a seed cap and there is no evidence that a plant has

already begun to grow.

E Where are the male and female parts of a plant found?

In the flower

F Briefly explain how seeds are dispersed.

Seeds can be spread by wind, water and animals

G Describe how birds and insects help to pollinate the mature tree.

Birds and insects are attracted to the color and sweet nectar of flowers.

They brush off pollen from the male parts of the plant and pour the

granules onto the tough pistons of the female parts.



Part 2: Animal life cycles

Read the following text about the life cycle of a chicken and use the information

to answer the questions that follow.

1. Draw a picture for each stage in the life cycle of a chicken. Link the stage

with arrows. Use the following words as clues: hen and rooster; egg;

hatch; more feathers; rooster.

Drawing must portray the following:

The hen and rooster mating.

The egg developing inside the hen before she lays it.

The egg hatch and a chick is born.

The chick develops feathers and grows.

The chick grows into an adult hen or rooster.

2. Write the approximate time it takes for one stage to lead to the next.

3. Write a sentence underneath each picture to say what stage of the life

cycle of the chicken is shown.

Hen and

rooster

mate

Chicken

develops

in egg

Chick

hatch

Chick

grows

Chicken

grows up

After about 24 hours,

the hen can lay eggs

The embryo inside an

egg grows into a chick

in 21 days.

After about four

weeks, the chicks

grow more feathers

Chicks are fully grown

within six months

The life cycle of a chicken



Topic Revision Topic Revision Topic Revision Topic Revision ---- 5555 ((((p 58p 58p 58p 58))))

Match the words in Column A with the correct meaning in Column B.

A B

1-Reproduction A-Transfer of pollen from male to female parts of

flowers.

2-Pollution B-Joining of male and female seed

3-Fertilisation C-Fully grown

4-Life cycle D-The order in which something happens

5-Mature E-Stages in the life of all living things

6-Germinate F-Begin to sprout or grow into a seedling

7-Sequence G-Making offspring or babies

1. Which of the following would most probably happen if plants and animals

stopped reproducing? Choose the correct answer from the selection below:

a. Living things would just live longer and longer.

b. There would be more plants on Earth.

c. All life on Earth would eventually die out.

2. For each of the following sentences, say whether it is true or false.

T F

Fish generally take very good care of their eggs.

Elephants teach their young how to survive.

Birds give birth to live young.

All life cycles are of equal length.

A new generation of a plant is produced through reproduction.

Plants continue to grow throughout their lives.

The stigma is the male part of the flower.

An adult living thing can also be described as being mature.



3. Complete the following sentences by using the words ‘before’ or ‘after’.

a. Seedlings develop _________________________________ germination.

b. __________________________a baby is born, it is a developing embryo.

c. A pollen tube grows ________________pollen has landed on the stigma.

d. Seeds are produced ________________________________fertilisation.

e. ___________________________seed dispersal, a seedling can develop.

f. Pregnancy occurs __________________________________fertilisation.



Topic Revision Topic Revision Topic Revision Topic Revision ---- 5 (bl.58) (MEMO)5 (bl.58) (MEMO)5 (bl.58) (MEMO)5 (bl.58) (MEMO)

Match the words in Column A with the correct meaning in Column B.

A B

1-Reproduction A-Transfer of pollen from male to female parts of

flowers.

2-Pollination B-Joining of male and female seed.

3-Fertilisation C-Fully grown

4-Life cycle D-The order in which something happens.

5-Mature E-Stages in the life of all living things.

6-Germinate F-Begin to sprout or grow into a seeding.

7-Sequence G-Making offspring or babies.

1. Which of the following would most probably happen if plants and animals

stopped reproducing? Choose the correct answer from the selection below:

a. Living things would just live longer and longer.

b. There would be more plants on Earth.

c. All life on Earth would eventually die out.

2. For each of the following sentences, say whether it is true or false.

T F

Fish generally take very good care of their eggs. x

Elephants teach their young how to survive. x

Birds give birth to live young. x

All life cycles are of equal length. x

A new generation of a plant is produced through reproduction. x

Plants continue to grow throughout their lives. x

The stigma is the male part of the flower. x

An adult living thing can also be described as being mature. x



3. Complete the following sentences by using the words ‘before’ or ‘after’.

a. Seedlings develop after germination.

b. Before a baby is born, it is a developing embryo.

c. A pollen tube grows after pollen has landed on the stigma.

d. Seeds are produced after fertilisation.

e. After seed dispersal, a seedling can develop.

f. Pregnancy occurs after fertilisation.

t5 – life cycles · seeds will germinate and grow into new plants. plants can die at any stage of...

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