Chapter 8 of 8

All 8 chapters
  1. 1Plant parts and their jobs, readunderstood
  2. 2From seed to seedling, readunderstood
  3. 3A fair test with plants, readunderstood
  4. 4Light, water and plant health, readunderstood
  5. 5Leaves make food, readunderstood
  6. 6Flowers and pollination, readunderstood
  7. 7How seeds travel, readunderstood
  8. 8The life cycle of a plant, readunderstood

S2.1.8 Chapter 8

The life cycle of a plant

Where does a bean plant come from, and where does it go?

Your guess

Pick one before you read on. It is fine to be wrong.

Your guess

  • You picked A. Read on. At the end, the chapter comes back to your guess.

  • You picked B. Read on. At the end, the chapter comes back to your guess.

  • You picked C. Read on. At the end, the chapter comes back to your guess.

By the end you can

  • Draw the life cycle of a flowering plant
  • Compare the life cycle of a bean plant with a fruit tree

A bean plant starts as a seed. It ends with new seeds. Then the new seeds can start again.

This round trip is a life cycle. A life cycle is the stages of a life, in order.

Draw it first

Draw the life cycle

  1. A ring of six boxes with arrows going round. Down the left side: seed, seedling, adult plant. The words starts to grow sit by the first arrow. Along the bottom an arrow goes to flowers. Up the right side: flowers, fruit, seeds spread. The word pollination sits by the arrow from flowers to fruit. An arrow along the top leads from seeds spread back to seed.seedseedlingadult plantstarts to grow

    1 Draw boxes for seed, seedling and adult plant. Join them with arrows.

  2. A ring of six boxes with arrows going round. Down the left side: seed, seedling, adult plant. The words starts to grow sit by the first arrow. Along the bottom an arrow goes to flowers. Up the right side: flowers, fruit, seeds spread. The word pollination sits by the arrow from flowers to fruit. An arrow along the top leads from seeds spread back to seed.seedseedlingadult plantstarts to growflowersfruitpollination

    2 Add flowers and fruit. Write pollination on the arrow between them.

  3. A ring of six boxes with arrows going round. Down the left side: seed, seedling, adult plant. The words starts to grow sit by the first arrow. Along the bottom an arrow goes to flowers. Up the right side: flowers, fruit, seeds spread. The word pollination sits by the arrow from flowers to fruit. An arrow along the top leads from seeds spread back to seed.seedseedlingadult plantstarts to growflowersfruitpollinationseeds spread

    3 Add seeds spread. Draw an arrow back to seed.

A seed starts to grow. It becomes a seedling. A seedling is a very young plant.

The seedling grows into an adult plant. The adult plant makes flowers.

Pollen reaches the sticky top of a flower of the same kind. This is pollination. Then seeds grow. The base of the flower swells into a fruit.

The seeds spread. A seed that lands in good ground starts to grow. The cycle goes round again.

A ring of six small pictures with arrows going round. Down the left side: a seed, a seedling and an adult plant. An arrow along the bottom leads to a flower. Up the right side: a flower, a fruit and seeds spread. An arrow along the top leads back to the seed. Labels: seed, seedling, adult plant, flower, fruit, seeds spread.seedseedlingadult plantflowerfruitseeds spread
The stages go round. The seeds start the cycle again.

Not every plant takes the same time. Look at a bean plant and a mango tree.

See it three ways

As a picture

Two bars. The top bar is short. It is labelled bean plant. It has a part labelled grows, then a part labelled seeds, then the word dies. The bottom bar is long. It is labelled mango tree. It has a part labelled grows, then a part labelled fruit, with the words again and again above it. An arrow at the end shows it goes on.bean plantgrowsseedsdiesmango treeagain and againgrowsfruit

In words

A bean plant makes new seeds in a few months. Then it dies. A mango tree grown from a seed is slower. It may take five years or more to flower. Then it flowers and fruits again and again for many years.

Three small pictures joined by arrows. A plant with leaves, labelled plant. Some seeds on the ground, labelled seeds. A seedling with two leaves, labelled new plants. Labels: plant, seeds, new plants.plantseedsnew plants
A bean plant makes seeds once, then dies. Its seeds grow into new plants.

Try it

Find the stages of one plant

You need: paper, a pencil, a patch of weeds or a garden.

Be safe: Do not touch or taste plants you do not know. Some sting or are poisonous. Wash your hands after.

  1. Find a kind of plant that grows in many places. A common weed is good.
  2. Look for a seedling, a bigger plant and a plant in flower.
  3. Look for one with fruit or seeds.
  4. Draw each plant in a row on your paper. Put them in order.
  5. Draw arrows between them. Then draw an arrow from the last back to the first.

What you will see: One kind of plant shows many stages at the same time. Put in order, they make the life cycle. The last stage makes seeds. The seeds start the first stage again.

If you cannot try it, this is what happens.
Three plants of one kind stand side by side on the ground. The first is very small, labelled seedling. The second is taller, labelled bigger. The third is the tallest and has a flower, labelled in flower.seedlingbiggerin flower

A wrong idea many people have

Every plant dies after it makes seeds.

Why it feels right: Bean and maize plants go dry and brown after their seeds form.

The test that breaks it: Find a fruit tree near you. A mango or a lemon will do. Ask the owner how long it has stood there. Ask how many times it has made fruit. The answer is many times. It is the same tree each time.

What is true: A bean plant makes seeds once, then dies. A mango tree makes fruit again and again for many years.

Key words

life cycle
the stages of a life, in order, which come round again.
seedling
a very young plant that has just grown from a seed.
pollination
pollen reaching the sticky top of a flower of the same kind.
fruit
the part of a plant that holds the seeds.

Back to your guess

The answer is A: A plant grows, makes seeds, and the seeds grow new plants.

A plant grows from a seed. It flowers and makes new seeds. The new seeds grow into new plants.

Check yourself

Try each one before you look. A wrong answer tells you where to go next.

  1. Which list puts the stages in the right order?

    Tap your answer.

    1. Not this one. A seed grows into a seedling first. Then it becomes an adult plant and flowers. Go to S2.1.2. Try another.

    2. Not this one. The flower comes after the adult plant. The seed comes first. Try another.

    3. Not this one. The seedling must grow into an adult plant before it can flower. Go to S2.1.2. Try another.

    4. Yes, that is right. Each seed grows into a seedling, then an adult plant. The adult plant flowers and makes fruit.

    See the answer

    Seed, seedling, adult plant, flower, fruit with seeds

    Each seed grows into a seedling, then an adult plant. The adult plant flowers and makes fruit.

    • If you chose A: A seed grows into a seedling first. Then it becomes an adult plant and flowers. Go to S2.1.2.
    • If you chose B: The flower comes after the adult plant. The seed comes first.
    • If you chose C: The seedling must grow into an adult plant before it can flower. Go to S2.1.2.

  2. What must happen between the flower and the fruit?

    Tap your answer.

    1. Not this one. That comes later, after the seeds have spread. Try another.

    2. Yes, that is right. Pollen must reach the sticky top of the flower. Then seeds grow and the base swells into a fruit.

    3. Not this one. Leaves do not make fruit. Pollen reaching the sticky top does. Go to S2.1.6. Try another.

    See the answer

    Pollination

    Pollen must reach the sticky top of the flower. Then seeds grow and the base swells into a fruit.

    • If you chose A: That comes later, after the seeds have spread.
    • If you chose C: Leaves do not make fruit. Pollen reaching the sticky top does. Go to S2.1.6.

  3. What happens to a bean plant after it makes its seeds?

    Tap your answer.

    1. Not this one. That is a tree, like a mango. A bean plant makes seeds once. Try another.

    2. Not this one. A plant does not turn back into a seed. The new seeds start new plants. Try another.

    3. Yes, that is right. A bean plant makes seeds once. Then it dries up and dies. Its seeds start new plants.

    See the answer

    It dies.

    A bean plant makes seeds once. Then it dries up and dies. Its seeds start new plants.

    • If you chose A: That is a tree, like a mango. A bean plant makes seeds once.
    • If you chose B: A plant does not turn back into a seed. The new seeds start new plants.

  4. A bean plant and a mango tree both grow from seeds. Which takes longer to flower?

    Tap your answer.

    1. Yes, that is right. A mango tree may take five years or more to flower. Then it fruits again and again.

    2. Not this one. A bean plant makes seeds in a few months. A mango tree may take five years or more. Try another.

    3. Not this one. They do not. A bean plant is quick. A mango tree may take five years or more. Try another.

    See the answer

    The mango tree

    A mango tree may take five years or more to flower. Then it fruits again and again.

    • If you chose B: A bean plant makes seeds in a few months. A mango tree may take five years or more.
    • If you chose C: They do not. A bean plant is quick. A mango tree may take five years or more.

  5. From an earlier chapter

    Amina grows two bean plants. One is in the light, one in a dark box. She gives the dark one more water. Is it a fair test?

    Tap your answer.

    1. Not this one. A fair test changes one thing only. She also changed the water. Go to S2.1.3. Try another.

    2. Yes, that is right. She changed the light and the water. A fair test changes only one thing.

    See the answer

    No. She changed two things.

    She changed the light and the water. A fair test changes only one thing.

    • If you chose A: A fair test changes one thing only. She also changed the water. Go to S2.1.3.

  6. Draw the life cycle of a flowering plant. Write each stage.

    See the answer

    A ring of boxes joined by arrows. Seed, seedling, adult plant, flowers, fruit, seeds spread. An arrow goes back to seed.

    The cycle goes round. The seeds start new plants.

  7. Look at the picture. Which stage goes in the dashed box?

    A ring of small pictures joined by arrows. Five have a name. One is a dashed box with a question mark. Labels: seed, seedling, adult plant, fruit, seeds spread, ?.seedseedlingadult plant?fruitseeds spread
    Tap your answer.

    1. Not this one. Seeds spread comes after the fruit. The box sits before the fruit. Try another.

    2. Not this one. A seedling comes right after the seed. It sits on the left. Try another.

    3. Yes, that is right. The adult plant comes before the box. The fruit comes after it. A flower grows between them.

    See the answer

    Flower

    The adult plant comes before the box. The fruit comes after it. A flower grows between them.

    • If you chose A: Seeds spread comes after the fruit. The box sits before the fruit.
    • If you chose B: A seedling comes right after the seed. It sits on the left.

  8. In a flowering plant's life cycle, what grows into a new plant?

    Tap your answer.

    1. Yes, that is right. A seed holds a tiny plant and its food. When it lands in good ground, it grows into a new plant.

    2. Not this one. A flower makes seeds. A new plant grows from a seed, not from a flower. Try another.

    3. Not this one. Pollen helps a seed to form. It does not grow into a plant. Try another.

    See the answer

    A seed

    A seed holds a tiny plant and its food. When it lands in good ground, it grows into a new plant.

    • If you chose B: A flower makes seeds. A new plant grows from a seed, not from a flower.
    • If you chose C: Pollen helps a seed to form. It does not grow into a plant.

Keep it

Copy this into your exercise book.

A flowering plant goes round a life cycle. It goes seed, seedling, adult plant, flower, fruit, seeds, and round again. A bean plant makes seeds once, then dies. A mango tree fruits again and again for many years.

Draw: A ring of boxes. Seed, seedling, adult plant, flowers, fruit, seeds spread.

Reading with a child? A short page for the adult: what this chapter teaches and three questions to ask.

No internet tomorrow? Save the whole book as one file (922 KB). It opens on any phone.