Plants Germination
Primary 4 · Science and Elementary Technology
Plants Germination
Lesson 5 of 5
15 min
Let's begin
At lunch, Uwase eats cassava, Irish potatoes, isombe and beans. "Today you ate a root, a stem, some leaves and some seeds!" says her teacher. Uwase laughs. Which is which?
| Part | Its jobs | Parts we eat |
|---|---|---|
| Roots | hold the plant firmly in the soil; take in water and mineral salts; some store food | cassava, sweet potato, carrot |
| Stem | holds up the leaves, flowers and fruits towards the light; carries water up from the roots and food from the leaves to other parts; some store food | sugarcane; Irish potato (an underground stem) |
| Leaves | make food for the plant, using sunlight, water and air; let out water vapour and oxygen | cassava leaves (isombe), amaranth (dodo), cabbage |
| Flowers | make seeds; colours and sweet smells bring bees and butterflies, which carry pollen from flower to flower | cauliflower |
| Fruits | protect the seeds and help spread them | avocado, mango, banana, tomato |
| Seeds | grow into new plants | beans, maize, rice, groundnuts, soya |
An Irish potato grows under the ground, but it is a swollen stem called a tuber. Look at its "eyes": they are buds, and each one can sprout into a new plant. Cassava and sweet potato, on the other hand, are swollen roots.
When a bird eats a ripe fruit, it may drop the seeds far away. Some fruits burst open and throw out their seeds, like bean pods drying in the sun. Spreading seeds gives new plants room to grow.
Put a white flower, or a leafy stem, in a glass of water coloured with blue ink. The next day, look at the petals and leaves: blue lines appear! The coloured water travelled up the stem to the flower and leaves.
Tip
Roots drink, the stem carries, leaves cook, flowers make seeds
Try each one first, then tap Show answer to check.
Which part of a plant makes its food?
Answer: The leaves, using sunlight, water and air.
Is an Irish potato a root or a stem? How do you know?
Answer: A stem (a tuber). It has eyes, which are buds that grow new shoots.
Which part of the cassava plant do we eat as isombe?
Answer: The leaves.
In the ink experiment, what makes the petals turn blue?
Answer: The stem carries the coloured water up to the flower.
Why do bees visit flowers, and how does this help the plant?
Answer: They come for the sweet nectar and carry pollen from flower to flower, which helps the plant make seeds.
What you learned today
Sources and credits
The exercises (Try it yourself and the practice questions) are written by Ganzaa.
This lesson adapts CC BY-SA material and is shared under CC BY-SA 4.0.
Quick check
Which part of a plant uses sunlight, water and air to make food?
