What makes your sandwiches go bad when you leave them in your school bag for a long time?

• It's because of things called bacteria and fungi. Although it may surprise you, a mushroom is a type of fungi, a type that's actually good to eat. Other types of fungi can be poisonous and very bad for your health. They can be large or so small that you don’t even notice it.

• Bacteria are very tiny and you need powerful microscope just to see them. Some bacteria can make you sick so it’s often a good idea to avoid dangerous bacteria when you can. Although a lot of bacteria can be harmful, other types are used to help us make foods like cheese and yoghurt.

• Perhaps the most important thing fungi and bacteria do are to make things rot, returning all the nutrients back to the earth. Without the help of bacteria and fungi, most of our rubbish would be extremely difficult to get rid of, piling up constantly and leaving a bad smell too.

 

Moldy Bread Activity:

• Find a clear plastic dish and put a piece of bread in it, leaving the bread for a few days until it starts going moldy.

• Take the moldy bread and investigate what it looks like under a microscope. Experiment with different lenses and focuses to get different a view of what the mold looks like. After a closer inspection of mold will you be less likely to eat those old sandwiches you find in your schoolbag?