Plants breathe, just like animals. A lot of children don’t really understand this, and it makes plants seem less alive than they truly are. So here is a cheap experiment you can do at home with your kids to teach them about how plants breathe – something that might just spark a life-long interest in botany!
What you need:
A transparent bowl or jug
Some luke warm water
A newly picked plant leaf
A small stone or pebble
How to do it:
Fill your transparent bowl with luke warm water.
Pop your freshly picked leaf inside and make sure its fully submerged by placing the pebble on top of it.
Put the bowl in a sunny spot and wait a few hours. You can check on it every hour and see how it progresses.
You’ll see that as time goes on, more and more bubbles form on the surface of the leaf – this is respiration, or how the leaf breathes.
This is a rose leaf after about an hour under water. Note all the air bubbles collecting on the underside of the leaf.
How respiration works:
When a plant photosynthesises (makes energy from sunlight), it takes up carbon dioxide (CO2) from the air. It uses the CO2 to make energy, and when it’s done, it produces oxygen as a by-product (something that comes out of photosynthesis that the plant doesn’t need anymore). So because the plant doesn’t need all this air anymore, it lets it out through tiny holes in the leaves called stomata.
Normally you can’t see this happening, but because the leave is underwater, you can see the air bubbles forming and becoming trapped on the surface of the leaf. When you see this, you’re watching a plant breath in real time! Isn’t that amazing?