Term 1 Topic 1 Plants and food

• Plants make their own food (glucose sugar) by a process called photosynthesis.
• Photosynthesis takes place mainly in the leaves.
• During photosynthesis the plant uses sunlight energy, carbon dioxide (from the air) and water to make glucose sugar.
• Plants change some of the glucose sugar into starch which they store in their leaves, stems and roots, flowers, fruits and seeds.

• Greet the learners.
• Tell them that as humans, we need food to stay alive.
• Ask the learners where they get their food from:

Possible answers: The supermarket; growing vegetables; milk from cows; etc.

• Ask the learners where animals get their food from:

Possible answers:  Grazing in the field; fed by the farmer, etc.

• Ask the learners if they can remember what they learnt about plants in

     Grade 5:

Answers could include –

• We have many different plants in South Africa.
• Plants and animals depend on each other. (Remind them that they learnt about the food chain and that all animals depend on plants as their primary source of food).
• Plants and animals depend on resources, such as air, water, soil and food.
• Now ask the learners where they think plants get their food from? Can they remember what they learnt in Grade 5 about green plants?  Allow time for a brief discussion.
• Explain that green plants make their own food using sunlight energy, water and carbon dioxide.
• Ask the learners if they know what we call the process used by plants to make their own food.

Answer:  Photosynthesis.

• Explain that photosynthesis is the process that plants use to change the energy from sunlight into energy for food.
• Ask the learners if they recently took a “selfie” (photograph) of themselves.
• Ask them what the important things are to think about when you take a photograph.

Possible answers:  Position of person; shadow; light, etc.

• Tell them that we need proper light to take a good photograph.
• A plant needs light and other things to make food.
• The word “photosynthesis” has two parts: photo and synthesis (write this on the board).

photo means “light”

synthesis means “to put together”

The plant uses light energy to make food.

• Ask the learners: Do you think all plants can make their own food?

Answer:  No, only green plants can make their own food.  Plants that cannot make their own food are called parasites.

• Have large pictures of the:

Sun; green plant with roots and green leaves.

• Have the following words written on large pieces of cardboard:

Light energy, carbon dioxide, oxygen, soil and water. 

• Select 8 learners (or ask for volunteers) to participate in this activity.
• Provide each learner with a picture or word poster.

Ask the learners to role play the sun; the light energy, the plant with green leaves and roots; carbon dioxide, oxygen, soil and water as you explain the process of photosynthesis.

The plant uses carbon dioxide from the air, energy from sunlight and water (and mineral salts) from the soil to make food. 

This process (Photosynthesis) takes place in the green leaves of the plant and makes (produces) oxygen that goes back into the air.

• Now give more groups of learners an opportunity to act out the process and let the rest of the learners provide comments and / or correct the “actors” if they make a mistake.

• Tell the learners that we discovered how photosynthesis works in the previous activity.
• It is important for us to understand all the different parts of photosynthesis.
• Present an overview of photosynthesis by using PRESENTATION 1: Photosynthesis.
• Explain the process of photosynthesis to learners using the illustration provided in WORKSHEET A: The Process of Photosynthesis
• Chlorophyll captures the sunlight energy.
• This energy splits the water into hydrogen and oxygen.
• The oxygen releases (goes back) into the air.
• Glucose (sugars) is made using the hydrogen and carbon dioxide.
• These sugars are moved from the leaves to other parts of the plants where they are stored.
• The water in the plant veins carries the sugars.
• When the sugars reach the places where they are stored, they are changed into starch.
• Ask the learners: Do you know where the plants store starch?

Answers could include:

• leaves (cabbage, spinach, lettuce)
• fruit (apples, banana, peaches)
• stem (sugar cane)
• seeds (wheat or mealies)
• flowers (broccoli or cauliflower)
• roots (carrots or beetroot)

• Ask learners to each collect a green leaf during break time.
• Divide the class into 4 groups:
• One group will place their leaves somewhere in the classroom where there is sun.
• A second group will place their leaves in a container with water near a window.
• A third group will place their leaves under their desks.
• The last group will place their leaves in water in a dark place (e.g. a cupboard).
• After a week, the learners will document the status of their leaves on WORKSHEET B: Leaf Experiment.

• Teacher to use WORKSHEET B: MEMORANDUM to mark the learners’ work.

• Show Video Clip 1: Photosynthesis (3:41 min.).

Title:  Photosynthesis | The Dr. Binocs Show | Learn Videos For Kids.

• Remind the learners that:
• Photosynthesis is the process inside plants that changes the sun’s energy into a form of energy that animals can eat.
• Plants change the glucose into starch (ask learners to mention a few examples).

Plants then store this food in different parts of the plant that an animal (or human) will eat.  This can be in the leaves or roots or stems or flowers or seeds or fruits.

• Hand out WORKSHEET C: Food from Photosynthesis.
• Provide learners with old magazines or supermarket advertisements from newspapers that contain pictures of different plant products. These could include sugar cane, tomatoes, lettuce, sunflower seeds, apples, carrots, etc.
• Learners must search for these pictures, cut them out and paste them on the worksheet.
• Under each picture, they should identify the part of the plant that we eat, e.g. leaves, stem or fruit.

• Teacher to use WORKSHEET C: MEMORANDUM to mark the learners’ work.

• For this part of the lesson the teacher will need different types of food.
• Remind learners that plants make glucose, but they store starch.
• Ask learners: Do you know what the difference is between a starch and a sugar?
• Tell them that there is a test that can be done to find out whether a food contains starch or not. This test is called the Iodine Starch Test.

WARNING: Do not allow the learners to taste any of the products used in the activity.

• Display a variety of food products cut into small pieces in containers on the table.
• Tell learners that if we drop iodine onto food, it will turns blue if it contains starch.
• Divide the class into different groups and give each group an opportunity to come to the table to conduct the Iodine Starch Experiment: Learners select a variety of food types, place each food item into a separate bowl and use a dropper to drop iodine onto the different foods.
• Let learners complete WORKSHEET D: Iodine Starch Test Experiment.

• Teacher to use WORKSHEET D: MEMORANDUM to mark the learners’ work.