Plants Germination
Primary 4 · Science and Elementary Technology
Plants Germination
Lesson 2 of 5
15 min
Let's begin
Keza soaks a bean in water overnight. In the morning it is fat and soft. She peels off its skin and gently splits it into two halves. Tucked inside she finds something tiny, like a curled-up baby plant!
A bean has two cotyledons. A maize grain has only one cotyledon, and most of its food is stored beside it in the grain.
Roots always grow down and shoots always grow up, even if you plant the seed upside down!
Tip
R before P: the Radicle comes first, then the Plumule
The root goes down to drink; the shoot goes up to the light.
Try each one first, then tap Show answer to check.
Which part comes out of the seed first?
Answer: The radicle (the baby root).
What are the cotyledons for?
Answer: They store food for the young plant until its leaves can make food.
Why does a dry bean get fat when you soak it overnight?
Answer: It soaks up water and swells.
Put these in order: the first leaves open; the seed coat splits; the seed swells; the plumule grows up; the radicle grows down.
Answer: The seed swells → the seed coat splits → the radicle grows down → the plumule grows up → the first leaves open.
Mugisha plants a bean upside down. Which way will its root grow?
Answer: Down. Roots always grow down and shoots always grow up.
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
Match each part of a bean seed to what it is.
Tap one on the left, then its partner on the right.
