PAGE 1: How we will learn OVERVIEW ======== Plants are living things, just like people and animals. In this sub-strand you will find out how we know that plants are alive, name the external parts of a plant and learn what each part does. You will also learn why we must take care of plants and how you can do it at school and at home. ## Strand 1.0: Living Things and their Environment Sub-strand 1.1: Plants Suggested lessons: 12 ## What this sub-strand covers • Characteristics of plants as living things • Functions of external parts of plants ## Source • KICD Grade 4 Science and Technology Curriculum Design (Revised 2024) — Strand 1.0 Living Things and their Environment, Sub-strand 1.1 Plants ## Learning outcomes By the end of the sub-strand, the learner should be able to: a) identify characteristics of plants as living things b) describe functions of external parts of plants c) appreciate the need to care for plants ## Key inquiry questions 1. Why are plants grouped as living things? ## Learning experiences • search for information from print and non- print materials on characteristics of plants as living things and discuss with peers • take a walk in the school compound and adjacent environment to observe, discuss and record evidence that plants: grow, reproduce, remove waste, respond to changes in their environment and die • Note: observes safety while handling different types of plants • observe young plants/seedlings, draw and label their parts and share with peers (roots, stems and leaves) • discuss the functions of external parts of plants and share with peers • use digital applications to draw, paint and label external parts of a plant ## Core competencies • Communication and Collaboration: The learner develops speaking and listening skills as they discuss the functions of external parts of plants. • Digital literacy: The learner develops manipulative skills as they interact with digital media to draw, paint and label external parts of a plant. ## Values • Unity: The learner cooperates in taking turns while they observe young plants/seedlings, draw and label their parts and share with peers. • Respect: The learner listens to and appreciates others’ opinions during discussions on the characteristics of plants. ## Pertinent and contemporary issues • Safety and Security: The learner observes safety while handling different types of plants as they take a walk in the school compound and adjacent environment to observe, discuss and record characteristics of plants as living things. ## Links to other learning areas • Agriculture and Nutrition: The learner uses information on characteristics of plants as living things in the study of different types of crops. PAGE 2: Lesson 1: Plants are living things — Characteristics of plants as living things LESSON 1: PLANTS ARE LIVING THINGS ================================== ## What you will learn • State the characteristics that show plants are living things. • Tell the difference between a living plant and a non-living object. Curriculum outcomes: a) identify characteristics of plants as living things ## Introduction Put a stone and a bean seed in wet soil and wait two weeks. The stone stays the same, but the bean seed sprouts and grows leaves. What makes the bean seed different from the stone? ## Notes Everything around us is either living or non-living. A stone, a chair and a plastic bottle are non-living. A dog, a person and a mango tree are living. Plants are grouped as living things because they show the characteristics of life. ### Characteristics of plants as living things - **Plants grow.** A small maize seedling becomes a tall maize plant. A young tree gets taller and its stem becomes thicker every year. - **Plants reproduce.** Reproduce means to make new plants of the same kind. Beans produce seeds that grow into new bean plants. Sugarcane and cassava can grow from pieces of stem planted in the soil. Sweet potatoes can grow from vines. - **Plants remove waste.** Plants give out extra water as water vapour through their leaves. They also give out oxygen, which is left over when they make food. Some plants shed old leaves. - **Plants respond to changes in their environment.** A plant kept near a window bends its stem towards the light. Roots grow towards water in the soil. The leaves of the touch-me-not plant (mimosa) fold up quickly when you touch them. - **Plants die.** When a plant gets old, or lacks water for a long time, it dries up and dies. Maize plants dry up after the maize is harvested. PAGE 3: Lesson 1: Plants are living things — Example 1 Plants also need food, water and air to stay alive. Unlike animals, green plants make their own food in their leaves using sunlight, water and air. ### How is a plant different from a non-living thing? A non-living thing such as a stone does not grow, does not reproduce, does not remove waste, does not respond to changes and does not die. A plant does all of these things. Plants do not move from place to place like animals, but their parts move slowly: leaves turn towards light and roots grow deeper into the soil. ## Key words • living thing — something that grows, reproduces, removes waste, responds to changes and dies • reproduce — to make new young ones of the same kind • respond — to react to a change around it, such as light or touch • seedling — a young plant that has just grown from a seed ## Worked examples ### Example 1 A potted plant placed near a window bends towards the window after a few days. Which characteristic of living things does this show? Working: 1. The plant is reacting to light coming through the window. 2. Reacting to a change around you is called responding. Answer: Plants respond to changes in their environment. ## Worked examples ### Example 2 A farmer plants maize seeds. Some months later there are new maize cobs with many seeds. Which characteristic does this show? Working: 1. New seeds that can grow into new maize plants have been made. 2. Making new plants of the same kind is reproduction. Answer: Plants reproduce. ## Activity: Nature walk: evidence that plants are alive You will need: Notebook and pencil, A hand lens if available 1. Walk in a group around the school compound with your teacher. 2. Look for evidence that plants grow (seedlings, new leaves), reproduce (flowers, fruits, seeds), remove waste (fallen leaves), respond (plants bending towards light) and die (dry plants). 3. Record what you see in a table with two columns: Characteristic and Evidence. 4. Do not pull up or damage plants. Do not touch thorny, stinging or unknown plants, and wash your hands after the walk. 5. Share your table with another group. PAGE 4: Lesson 1: Plants are living things — Answers to practice ## Practice 1. List five characteristics that show plants are living things. 2. The leaves of a touch-me-not plant fold when touched. What does this show? 3. Give one way in which plants remove waste. 4. Why is a stone not a living thing? ## Answers to practice 1. Plants grow, reproduce, remove waste, respond to changes in their environment and die. 2. Plants respond to changes in their environment. 3. They give out extra water as water vapour through their leaves (or give out oxygen, or shed old leaves). 4. It does not grow, reproduce, remove waste, respond to changes or die. ## Summary • Plants are living things. • Plants grow, reproduce, remove waste, respond to changes in their environment and die. • Green plants make their own food using sunlight, water and air. LESSON 2: EXTERNAL PARTS OF A PLANT =================================== ## What you will learn • Name the external parts of a plant. • Draw and label a young plant. Curriculum outcomes: b) describe functions of external parts of plants ## Introduction Pull a bean seedling gently out of wet soil and wash off the soil. You can see a part that was under the ground and parts that were above it. Each of these parts has a name. ## Notes The parts of a plant that we can see from outside are called external parts. The main external parts of a plant are: PAGE 5: Lesson 2: External parts of a plant — Drawing and labelling - **Roots** – the part that grows under the soil. Roots are usually white or brown and have many thin branches called root hairs near their tips. - **Stem** – the part that grows above the soil and holds up the leaves, flowers and fruits. The stem of a bean seedling is thin and green. The stem of a tree is hard and woody and is called a trunk. - **Leaves** – the flat, usually green parts that grow from the stem. Most leaves have a stalk that joins them to the stem and lines called veins. - **Flowers** – the often brightly coloured parts that grow on many plants when they are old enough. - **Fruits and seeds** – fruits grow from flowers and carry seeds inside them. Mangoes, oranges, bean pods and tomatoes are fruits. ### Looking at a young plant A seedling is a young plant. When you look at a bean or maize seedling you will clearly see the roots, the stem and the leaves. Seedlings do not yet have flowers or fruits. These come later as the plant grows. ### Drawing and labelling When you draw a plant: - Use a sharp pencil and draw clear, single lines. - Draw the soil line so it is clear which part is under the ground. - Write the labels on the side and join each label to the part with a straight line. - Give your drawing a title, for example A bean seedling. Not all plants look the same. A maize plant has many thin roots of about the same size, while a bean plant has one main root with smaller roots growing from it. The leaves of maize are long and narrow, while bean leaves are wide. [DIAGRAM] TYPE: svg ALT: External parts of a young plant: leaves, stem and roots PAYLOAD: CAPTION: External parts of a young plant: leaves, stem and roots [/DIAGRAM] PAGE 6: Lesson 2: External parts of a plant — Draw and label a seedling ## Key words • external parts — the parts of a plant we can see from outside • roots — the part of a plant that grows under the soil • stem — the part of a plant that holds up leaves, flowers and fruits • label — a name written next to a part in a drawing ## Worked examples ### Example 1 A learner digs up a maize seedling and sees many thin white threads under the ground. Which part is this? Working: 1. The part is under the soil. 2. The part of a plant under the soil is the root. Answer: Roots ## Activity: Draw and label a seedling You will need: Bean or maize seedlings grown in a tin or dug up carefully, Water to wash off soil, Pencil, paper or exercise book, A computer or tablet with a drawing application, if available 1. In pairs, take turns to hold the seedling and observe its roots, stem and leaves. 2. Draw the seedling and label the roots, stem and leaves. 3. If your school has a computer or tablet, use a drawing application to draw, paint and label the parts of a plant. 4. Share your drawing with your peers and check each other's labels. 5. Replant the seedling or put it in the school compost when done. ## Practice 1. Name three external parts that you can see on a bean seedling. 2. Which part of a plant grows from a flower and carries seeds? 3. What do we call the hard, woody stem of a tree? ## Answers to practice 1. Roots, stem and leaves. 2. The fruit. 3. A trunk. ## Summary • The external parts of a plant are the roots, stem, leaves, flowers, fruits and seeds. • A seedling has roots, a stem and leaves. • Label drawings with straight lines and clear names. PAGE 7: Lesson 3: Functions of the external parts of a plant LESSON 3: FUNCTIONS OF THE EXTERNAL PARTS OF A PLANT ==================================================== ## What you will learn • Describe the work of roots, stems, leaves, flowers and fruits. • Give examples of plant parts that store food. Curriculum outcomes: b) describe functions of external parts of plants ## Introduction When you eat cassava, you are eating a root. When you chew sugarcane, you are chewing a stem. When you eat sukuma wiki, you are eating leaves. Every part of a plant has work to do for the plant. ## Notes Each external part of a plant has a function. A function is the work that a part does. ### Roots - Hold the plant firmly in the soil so that wind and rain do not knock it over. - Take in (absorb) water and mineral salts from the soil. - Some roots store food for the plant. Carrots, cassava and sweet potatoes are roots that store food, which is why we eat them. ### Stem - Holds up the leaves so that they get sunlight, and holds up flowers and fruits. - Carries water and mineral salts from the roots up to the leaves, and carries food made in the leaves to other parts of the plant. - Some stems store food. Sugarcane stores sugar in its stem. An Irish potato is a swollen underground stem that stores food. ### Leaves - Make food for the plant using sunlight, water and air. This is why most leaves are green, flat and wide: they catch plenty of sunlight. - Allow air to move in and out of the plant through tiny openings. - Give out extra water as water vapour. - Some leaves are eaten as vegetables, such as sukuma wiki (kales), cabbage, spinach and cowpea leaves. ### Flowers - Flowers are the parts used for reproduction. After a flower is pollinated, part of it grows into a fruit with seeds. Bright colours and sweet smells attract insects such as bees, which help in pollination. ### Fruits and seeds - Fruits protect the seeds inside them. - Seeds grow into new plants. Many fruits are eaten by animals and people, which helps to spread the seeds to new places. All the parts work together. If the roots are cut, the leaves cannot get water and the plant wilts. If all the leaves are removed, the plant cannot make food. ## Key words • function — the work that a part does • absorb — to take in, as roots take in water from the soil • mineral salts — substances in the soil that plants need to grow well • wilt — to droop and go soft because of lack of water ## Worked examples ### Example 1 A learner puts a white flower with its stalk into a cup of water mixed with ink. After a day the petals have coloured lines. What does this show about the stem? Working: 1. The coloured water moved up from the cup into the petals. 2. It travelled through the stem. Answer: The stem carries water from the bottom of the plant to other parts. PAGE 8: Lesson 3: Functions of the external parts of a plant — Answers to practice ## Worked examples ### Example 2 Which part of each of these plants do we eat: cassava, sugarcane, sukuma wiki? Working: 1. Cassava grows under the soil and stores food: root. 2. Sugarcane stores sugar in its tall stem: stem. 3. Sukuma wiki is eaten for its leaves: leaves. Answer: Cassava – root, sugarcane – stem, sukuma wiki – leaves. ## Activity: Parts and their work You will need: A whole weed or seedling with roots, A white flower or celery stalk, a cup of water and ink or food colour, Chart paper 1. In groups, observe the plant and point to each external part. 2. Put the flower or celery stalk in coloured water and leave it until the next lesson. Observe what happens. 3. Discuss the function of each part and write it on a chart: roots, stem, leaves, flowers, fruits. 4. Present your chart to the class and listen to other groups' ideas. ## Practice 1. Give two functions of roots. 2. Which part of a plant makes food? 3. Why do many flowers have bright colours and sweet smells? 4. Name one stem that stores food. ## Answers to practice 1. They hold the plant firmly in the soil and absorb water and mineral salts. Some also store food. 2. The leaves. 3. To attract insects such as bees that help in pollination. 4. Sugarcane (or Irish potato). ## Summary • Roots hold the plant and absorb water and mineral salts. • The stem holds up the plant and carries water and food. • Leaves make food; flowers help the plant reproduce; fruits protect seeds. LESSON 4: CARING FOR PLANTS =========================== ## What you will learn • Explain why plants are important to people and animals. • Describe ways of caring for plants at school and at home. Curriculum outcomes: c) appreciate the need to care for plants ## Introduction Think about your breakfast, your desk and the shade where you rest at break time. Plants gave you most of these things. If we want plants to keep helping us, we must take care of them. PAGE 9: Lesson 4: Caring for plants — Why we need plants ## Notes ### Why we need plants - **Food.** We eat roots (cassava, carrots), stems (sugarcane), leaves (sukuma wiki, spinach), fruits (mangoes, bananas) and seeds (maize, beans). Animals such as cows and goats feed on grass and leaves. - **Air.** Green plants give out oxygen, which people and animals need to breathe. - **Shade and shelter.** Trees give shade and act as windbreaks. Birds and many small animals live in trees. - **Materials.** Timber for desks and houses, firewood, and fibres such as sisal and cotton come from plants. - **Medicine.** Some medicines are made from plants. - **Soil and water.** Roots hold soil together so that rain does not wash it away. Trees help protect the sources of rivers and streams. - **Beauty.** Flowers and hedges make our compounds beautiful. ### How to care for plants - Water young plants, especially in the dry season. Water in the morning or evening when it is cooler. - Put mulch (dry grass or leaves) around plants to keep the soil moist. - Add manure or compost so that plants get what they need to grow. - Remove weeds that compete with plants for water and space. - Put a fence or thorny branches around young trees to protect them from animals. - Walk on paths and do not step on flower beds or seedlings. - Do not pluck flowers, peel bark or break branches for fun. - Plant new trees, especially to replace ones that have been cut down. PAGE 10: Lesson 4: Caring for plants — Adopt a plant ### Staying safe around plants Some plants have thorns, sting (like the stinging nettle) or are poisonous. Do not touch or taste a plant you do not know, and wash your hands after working with plants. ## Key words • mulch — dry grass or leaves spread on the soil around plants to keep it moist • weed — a plant growing where it is not wanted • windbreak — a line of trees or hedge that slows down strong wind ## Worked examples ### Example 1 The school has planted young trees near the playground, but goats keep eating them. Suggest a way to care for the trees. Working: 1. The problem is animals eating the young trees. 2. The trees need protection until they are big. Answer: Put a fence or thorny branches around each young tree. ## Activity: Adopt a plant You will need: A young tree or potted plant in the school compound, Watering can or a used bottle, Dry grass for mulch 1. In your group, choose one young plant in the school compound to care for. 2. Remove the weeds around it, water it and spread mulch around it. 3. Make a simple chart to record each time you water it and how tall it grows. 4. Take turns so that every group member cares for the plant. 5. Tell the class how your plant changes over a few weeks. ## Practice 1. Give three reasons why plants are important. 2. Why should we put mulch around plants? 3. Name two things you should not do to plants in the school compound. ## Answers to practice 1. Any three: they give food, oxygen, shade, timber and firewood, medicine, they hold soil together, they make places beautiful. 2. Mulch keeps the soil moist so the plant does not dry up. 3. Any two: step on seedlings or flower beds, pluck flowers, peel bark, break branches. PAGE 11: Lesson 5: How plants grow — From a seed to a seedling ## Summary • Plants give us food, oxygen, shade, materials and medicine. • Care for plants by watering, mulching, weeding, adding manure and protecting them. • Do not touch or taste plants you do not know. LESSON 5: HOW PLANTS GROW ========================= ## What you will learn • Describe the changes as a seed becomes a seedling. • Record evidence that a plant is growing. Curriculum outcomes: a) identify characteristics of plants as living things ## Introduction A bean seed in moist soil does not stay a seed. After a few days a root and a shoot appear, and each week the young plant is taller than the week before. ## Notes Growth is one characteristic that shows a plant is a living thing. Growth means the plant becomes bigger and forms new parts. It is slow, so you notice it by watching the same plant for days or weeks, not for a single minute. ### From a seed to a seedling A seed holds a tiny young plant and a store of food. When a seed is planted in moist soil: - It takes in water and swells. - A root grows out and turns downward into the soil. - A shoot grows upward and becomes the stem. - The first leaves open. Once they turn green they begin to make food. The young plant is called a seedling. Bean seeds and maize seeds both grow this way if they are kept moist, but their leaves look different. Bean leaves are broad. Maize leaves are long and narrow. PAGE 12: Lesson 5: How plants grow — Evidence you can measure ### Evidence you can measure You do not have to guess that a plant is growing. You can measure it. - Once a week, measure the height from the soil to the tip of the plant. - Count the leaves. - Look at the stem. A tree stem also grows thicker, not only taller. - Check the roots if you are moving a seedling to a larger container. They become longer and grow more branches. Write the date, the height and the number of leaves in a table. If the numbers go up, the plant is growing. A stone measured in the same way does not grow. ### What a plant needs so that it can grow Growth uses food, water and air. Green leaves make food when they get sunlight. Roots take in water and mineral salts. A seedling kept in a dark place becomes pale and weak because its leaves cannot make food. A seedling that is never watered wilts, stops growing and may die. Adding manure or compost supplies mineral salts and helps the plant grow well. When you record a seedling over several weeks, you are collecting evidence that plants grow. That is the same kind of evidence you look for on a nature walk. ## Key words • growth — becoming bigger and forming new parts • shoot — the young stem that grows upward from a seed • mineral salts — substances from the soil that a plant needs in order to grow well ## Worked examples ### Example 1 A class plants maize on Monday. On Friday they see a small green shoot. Two weeks later the shoot is taller and has more leaves. Which characteristic of living things is this? Working: 1. The plant has become bigger and has formed new leaves. 2. Becoming bigger and forming new parts is growth. Answer: Plants grow. ## Worked examples ### Example 2 A seedling kept in a closed cupboard for a week is pale and weak, while a seedling by the window is green and firm. What was missing for the pale seedling? Working: 1. Green leaves need sunlight to make food. 2. The cupboard seedling had water but little or no light. Answer: Sunlight. Without light the leaves cannot make food, so the seedling does not grow well. PAGE 13: Lesson 5: How plants grow — Answers to practice ## Activity: Measure a seedling each week You will need: Bean or maize seeds, Tins or a small garden bed with soil, Water, A ruler, A notebook 1. In groups, plant a few seeds in moist soil and label the tin with your group name. 2. When the shoot appears, draw it and measure its height from the soil to the tip. 3. Once a week, record the date, the height and the number of leaves in a table. 4. Discuss what the table shows: the plant is growing. Compare it with a stone, which does not grow. 5. Water the seedlings and wash your hands. Do not taste seeds that have been treated with chemicals. ## Practice 1. What comes out of a seed first, the root or the leaves? 2. Give two measurements you can record to show that a plant is growing. 3. Why does a seedling become weak if it is kept in the dark? ## Answers to practice 1. The root grows out first and turns downward. The shoot and leaves follow. 2. Height of the plant and the number of leaves (also the thickness of a tree stem). 3. Its leaves cannot make food without sunlight. ## Summary • A seed swells, sends out a root and a shoot, and becomes a seedling. • Taller stems, more leaves and longer roots are evidence of growth. • Plants need water, air, sunlight and mineral salts in order to grow. PAGE 14: Lesson 6: Ways plants make new plants — New plants from stems LESSON 6: WAYS PLANTS MAKE NEW PLANTS ===================================== ## What you will learn • Describe how new plants grow from seeds, stem cuttings and bulbs. • Record evidence of reproduction in plants around the school. Curriculum outcomes: a) identify characteristics of plants as living things ## Introduction A mango tree can leave a seed inside its fruit, and that seed can become another mango tree. Sugarcane does something different: a piece of its stem can grow into a new plant. ## Notes Reproduce means to make new plants of the same kind. A plant that reproduces leaves young plants after it. This is one reason plants are grouped as living things. Plants do not all reproduce in the same way. You can find the evidence on a nature walk and in books or other materials. ### New plants from seeds Many plants grow flowers. Part of the flower becomes a fruit, and the fruit holds seeds. A maize cob is packed with seeds. A bean pod holds bean seeds. A mango fruit has a large seed inside. If a healthy seed is planted in moist soil, it can grow into a new plant of the same kind. Farmers eat some of the harvest and save some seeds to plant next season. Seeing fruits and seeds on a plant is evidence of reproduction. ### New plants from stems Some plants are grown from pieces of stem called cuttings. - Sugarcane is planted by laying pieces of stem in the soil. Buds at the joints grow into new shoots and roots. - Cassava is planted from stem cuttings. The cutting sends out roots and new leaves. - Sweet potato vines are long stems. When a vine is planted in a mound of soil, it grows new leaves and storage roots. You do not need a seed to get a new sugarcane, cassava or sweet potato plant. The stem itself can grow into one. PAGE 15: Lesson 6: Ways plants make new plants — Example 1 ### New plants from bulbs and underground stems An onion grows from a bulb. A bulb stores food, so a new shoot can grow from it. An Irish potato is a swollen underground stem. Each eye on the potato is a bud that can grow into a new potato plant. Some grasses send a stem along the ground, and a new plant forms where that stem touches the soil. ### Recording what you find In your notebook, make three columns: Plant, Part used to make a new plant, and Evidence I saw. For example, "Bean, seed, pods with seeds on the plant" or "Sugarcane, stem cutting, new shoots from a planted stem." Share the table with your group. Do not cut plants in the school compound unless the teacher gives you a cutting to plant. ## Key words • cutting — a piece of stem planted so that it grows into a new plant • bulb — an underground part, such as an onion, that can grow into a new plant • node — a joint on a stem where a bud or a leaf grows ## Worked examples ### Example 1 A farmer cuts sugarcane stems into pieces, covers them lightly with soil, and waters them. New shoots appear. Which characteristic of plants does this show? Working: 1. The pieces of stem are becoming new sugarcane plants. 2. Making new plants of the same kind is reproduction. Answer: Plants reproduce. ## Worked examples ### Example 2 Sort these into "grown from seed" and "grown from a stem": maize, cassava, beans, sweet potato. Working: 1. Maize and beans are planted as seeds. 2. Cassava is planted from stem cuttings and sweet potato from vines, which are stems. Answer: From seed: maize and beans. From a stem: cassava and sweet potato. PAGE 16: Lesson 7: Comparing roots, stems and leaves ## Activity: Search and share how plants reproduce You will need: Science books or class charts, A digital device if the school has one, Notebook 1. Search in print materials, and in non-print materials if you have them, for ways plants reproduce. 2. Write at least three ways: seeds, stem cuttings, and bulbs or underground stems. Add one example of each. 3. Discuss your findings with your group. Listen to examples you did not find yourself. 4. Walk in the compound only with the teacher and record any fruits, seeds or new shoots you can see without damaging plants. 5. Wash your hands after handling soil or plants. ## Practice 1. What is a cutting? 2. Name two plants commonly grown from pieces of stem. 3. Why is a fruit on a bean plant evidence of reproduction? 4. An Irish potato has eyes that sprout. What are the eyes? ## Answers to practice 1. A piece of stem that is planted so it grows into a new plant. 2. Any two: sugarcane, cassava, sweet potato. 3. The fruit holds seeds, and each healthy seed can grow into a new bean plant. 4. Buds on an underground stem. Each bud can grow into a new plant. ## Summary • Many plants reproduce by seeds held inside fruits. • Sugarcane, cassava and sweet potato can grow from stems. • Onions grow from bulbs, and potato eyes are buds on an underground stem. LESSON 7: COMPARING ROOTS, STEMS AND LEAVES =========================================== ## What you will learn • Distinguish a tap root from fibrous roots. • Describe differences in stems and leaves of common plants. Curriculum outcomes: b) describe functions of external parts of plants ## Introduction A carrot pulled from the soil shows one thick root. A maize plant pulled up carefully shows a bunch of thin roots instead. Both are roots, but they are built differently. ## Notes The external parts of a plant are the parts you can see: roots, stem and leaves on a seedling, and later flowers and fruits. These parts do the same kinds of work on every plant, but they do not all look the same. Comparing them helps you describe a plant clearly and explain what each part is for. ### Two kinds of roots - A tap root has one main root that grows deep, with smaller roots branching from it. Bean plants, carrots and mango trees have tap roots. A carrot is a tap root that has swollen to store food. The main root holds the plant firmly and reaches water deeper in the soil. - Fibrous roots are many thin roots of about the same size, growing from the base of the stem. Maize, grass and onions have fibrous roots. They spread out and hold the topsoil firmly, which helps stop soil from being washed away. Wash soil off a seedling gently so you can see which kind of root it has. Then replant it and water it. PAGE 17: Lesson 7: Comparing roots, stems and leaves — How to compare fairly ### Stems The stem holds the plant up and carries water and food. Stems differ. - A bean seedling has a soft green stem. - A tree has a hard woody stem called a trunk, protected by bark. - Sugarcane has a tall jointed stem that stores sugar. The joints are called nodes. - A sweet potato vine is a stem that creeps along the ground. - An Irish potato grows underground, but it is a stem, not a root. The eyes are buds. Roots do not have buds like these. ### Leaves Most leaves are green and have veins. The veins carry water and food. A leaf is usually joined to the stem by a stalk. - Maize and grass have long narrow leaves. - Bean and mango leaves are broader. - A banana leaf is very large. - Sukuma wiki and spinach are grown for their broad leaves, which people eat as vegetables. ### How to compare fairly Look at one part at a time. Draw two plants side by side and label the roots, stem and leaves. Write one sentence about how the roots differ and one sentence about how the leaves differ. If you use a tablet or computer, you can draw and paint the two plants in a drawing application and type the labels. Share the drawings and check one another's labels. [DIAGRAM] TYPE: svg ALT: A tap root has one main root. Fibrous roots are many thin roots of similar size. PAYLOAD: CAPTION: A tap root has one main root. Fibrous roots are many thin roots of similar size. [/DIAGRAM] PAGE 18: Lesson 7: Comparing roots, stems and leaves — Example 1 ## Key words • tap root — one main root with smaller roots branching from it • fibrous roots — many thin roots of about the same size • vein — a line in a leaf that carries water and food • trunk — the hard woody stem of a tree ## Worked examples ### Example 1 A learner compares a bean seedling and a maize seedling. The bean has one main root. The maize has many thin roots. Name each type. Working: 1. One main root with smaller branches is a tap root. 2. Many thin roots of similar size are fibrous roots. Answer: Bean: tap root. Maize: fibrous roots. ## Worked examples ### Example 2 Why is an Irish potato called a stem even though it grows underground? Working: 1. The potato has eyes, which are buds. 2. Buds grow into new shoots. That is a feature of a stem. Answer: It is an underground stem. The eyes are buds that can grow into new plants. ## Activity: Draw two seedlings and compare their parts You will need: A bean seedling and a maize or grass seedling, Water for washing soil off roots, Pencil and paper, A drawing application on a computer or tablet, if available 1. In pairs, observe the roots, stem and leaves of each seedling. Take turns so everyone handles the plants gently. 2. Draw both seedlings, show the soil line, and label roots, stem and leaves. 3. Write whether each plant has a tap root or fibrous roots, and one difference between the leaves. 4. If a digital device is available, draw, paint and label one plant in a drawing application and show it to your peers. 5. Replant the seedlings and wash your hands. PAGE 19: Lesson 7: Comparing roots, stems and leaves — Answers to practice ## Practice 1. What is the difference between a tap root and fibrous roots? 2. Name one plant with a tap root and one plant with fibrous roots. 3. What do the veins in a leaf do? 4. What is the woody stem of a tree called? ## Answers to practice 1. A tap root is one main root with smaller branches. Fibrous roots are many thin roots of about the same size. 2. Tap root: bean, carrot or mango. Fibrous roots: maize, grass or onion. 3. They carry water and food. 4. A trunk. ## Summary • Tap roots have one main root. Fibrous roots are a cluster of thin roots. • Stems may be soft, woody, jointed, creeping or underground. • Leaves differ in shape, but most are green and have veins. LESSON 8: FLOWERS, FRUITS AND SEEDS =================================== ## What you will learn • Describe the functions of flowers, fruits and seeds. • Explain the order from flower to fruit to seed to a new plant. Curriculum outcomes: b) describe functions of external parts of plants ## Introduction A hibiscus flower is bright, but its work is not only to look pretty. After insects visit it, part of that flower can grow into a fruit that holds seeds. ## Notes Roots, stems and leaves keep a plant alive from day to day. Flowers, fruits and seeds have a different job: they allow the plant to reproduce. You usually see them on a plant that has grown past the seedling stage. ### Flowers A flower is an external part. Many flowers have coloured petals and a scent. Bees, butterflies and other insects visit them to collect nectar, a sweet liquid in the flower. Pollen sticks to the insect and is carried to another flower. This is called pollination. After pollination, part of the flower grows into a fruit. Not all flowers look like a rose or a hibiscus. Maize has two kinds of flowers on the same plant. The tassel at the top sheds pollen. The silk on the young cob receives pollen. Each thread of silk leads to a place where a maize seed can form. ### Fruits A fruit develops from a flower and protects the seeds while they grow. Some fruits are soft and juicy, such as a mango, an orange, a banana or a tomato. Some are dry, such as a bean pod or a maize cob. People often cook tomatoes and bean pods as vegetables, but in science they are fruits because they carry seeds. The fruit keeps the seeds safe while they develop. When an animal eats the fruit, or a person carries it, seeds may be dropped in a new place and grow there. PAGE 20: Lesson 8: Flowers, fruits and seeds — Example 1 ### Seeds Inside a seed is a tiny young plant and stored food. The stored food feeds the young plant until its leaves open and start making food. Seeds differ in size and shape. A bean seed is large and easy to split open. A tomato seed is small. Farmers dry seeds and keep them in a cool, dry container so they do not rot or sprout before planting time. ### One story in order Flower, then fruit, then seed, then a new plant: that is reproduction by seed. When you draw a mature plant, label the roots, stem, leaves and any flower or fruit you can see. Use straight lines for the labels, write the names clearly, and give the drawing a title. If you can, also paint and label the plant using a digital drawing tool, then compare your labels with a chart. ## Key words • pollination — the transfer of pollen that allows a flower to start forming seeds • nectar — a sweet liquid in many flowers that attracts insects • fruit — the part that develops from a flower and carries the seeds ## Worked examples ### Example 1 A learner says a tomato is not a fruit because it is cooked in stew. How should you answer using the function of a fruit? Working: 1. A fruit develops from a flower and holds seeds. 2. A tomato develops from a flower and has seeds inside it. Answer: A tomato is a fruit because it comes from a flower and carries seeds. ## Worked examples ### Example 2 Put these in the order they happen: seed grows into a plant, flower is pollinated, fruit forms, new seeds are inside the fruit. Working: 1. Pollination happens to the flower first. 2. The fruit forms and holds the new seeds. 3. A seed can then grow into a new plant. Answer: Flower is pollinated, fruit forms, new seeds are inside the fruit, seed grows into a plant. PAGE 21: Lesson 8: Flowers, fruits and seeds — Label a flower, a fruit and a seed ## Activity: Label a flower, a fruit and a seed You will need: A flower, a fruit cut across by the teacher, and a large seed such as a bean, Hand lens if available, Pencil, paper and coloured pencils, Digital drawing tool if available 1. Observe the flower, the cut fruit and the seed. Do not taste anything unless the teacher says the food is safe to eat. 2. Draw the three items and label petal, fruit and seed. On the fruit, point to where the seeds are. 3. Discuss the function of each part with your group and write one sentence for each. 4. Use a digital device, if you have one, to paint and label a plant that shows a flower and a fruit. 5. Wash your hands after handling plant parts. ## Practice 1. What is pollination? 2. Why is a bean pod a fruit? 3. What two things are inside a seed? 4. What is the function of a fruit? ## Answers to practice 1. The carrying of pollen to a flower so that a fruit and seeds can start to form. 2. It develops from a flower and carries seeds. 3. A tiny young plant and stored food. 4. It protects the seeds. It can also help the seeds to be carried to new places. ## Summary • Flowers are the parts used in pollination. A fruit then develops and holds the seeds. • A seed contains a young plant and stored food. • The order is flower, fruit, seed, new plant. PAGE 22: Revision quiz REVISION QUIZ ============= Answer all the questions, then mark yourself on the Answers tab. 1. Which of these is a living thing? A. A stone B. A plastic bottle C. A bean plant D. A desk 2. A plant near a window bends towards the light. This shows that plants: A. reproduce B. respond to changes C. die D. remove waste 3. Name the characteristic of living things shown when a maize plant dries up after harvest. 4. Which part of a plant holds it firmly in the soil? A. Leaf B. Flower C. Root D. Fruit 5. Which part of a plant makes food? A. Leaves B. Roots C. Seeds D. Flowers 6. Water moves from the roots to the leaves through the: A. flower B. stem C. fruit D. seed 7. Cassava and carrots are examples of plant parts that store food. Which part are they? A. Stems B. Leaves C. Roots D. Flowers 8. What is the main function of a flower? 9. Which of these is a good way of caring for plants? A. Plucking flowers B. Stepping on seedlings C. Mulching and watering D. Peeling bark 10. Give two reasons why we should care for plants. 11. A seed takes in water, a root grows down and a shoot grows up. This is evidence that plants: A. Die B. Grow C. Are non-living D. Have no roots 12. Which plant is commonly grown from pieces of stem? A. Maize B. Sugarcane C. A carrot D. A stone ANSWERS ======= 1. C. A bean plant A bean plant grows, reproduces, removes waste, responds to changes and dies. 2. B. respond to changes Bending towards light is a response to a change in the environment. 3. Plants die. All living things die at the end of their lives. 4. C. Root Roots grow into the soil and anchor the plant. 5. A. Leaves Green leaves make food using sunlight, water and air. 6. B. stem The stem carries water and mineral salts up from the roots. 7. C. Roots Cassava and carrots are roots that store food. 8. Reproduction – it develops into a fruit with seeds. After pollination, part of the flower grows into a fruit that carries seeds. 9. C. Mulching and watering Mulching keeps soil moist and watering gives the plant the water it needs. 10. Any two: plants give us food, oxygen, shade, timber, firewood, medicine, and they hold soil together. People and animals depend on plants in many ways. 11. B. Grow The seed is becoming a larger plant with new parts. That is growth. 12. B. Sugarcane Sugarcane is planted from stem cuttings. Buds on the stem grow into new plants.