Fungi come in many shapes and sizes, ranging from single-celled yeasts and molds to enormous underground networks that can stretch for miles. They differ from plants in that they cannot produce their own food and instead consume and break down dead or living organisms. Fungi spread through tiny spores carried by wind and rain or through networks of underground hyphae. They are found virtually everywhere and play important roles in decomposition as well as having uses like leavening bread and brewing beer. The largest known fungus covers 2,200 acres in Oregon.

1. Fungi 1
Fungi Basics
• Yeasts are single-celled fungi, so they are
microbes. So is mould.
• Fungi are usually bigger than bacteria.
• If there is just one of them, we call it a
fungus.
• Fungi are more like animals than plants.
For one thing, fungi cannot make their
own food like plants do, but instead they
eat other organisms, as animals do.
• With fungi, there are good guys and
there are bad guys. Some make our food
go mouldy, and some cause diseases. But
they also break down dead plants and
animals, keeping the world tidier.
• We use some fungi to do things for us,
like make bread rise and brew beer.
These mushrooms are fungi, but they’re
big and they’ve got loads of cells, so
they’re not microbes. We’ll ignore these
for now.
Yeast cells

2. Fungi 2How They Get Around
• Individual fungi don’t move around.
• But they can spread by making tiny
spores (a bit like seeds) that are carried
by wind and rain and grow into new
fungus cells when they land.
• Some fungi, such as moulds, make long
threads of cells called hyphae. These
threads are what make mould look fuzzy.
Moulds can spread by growing and
extending their hyphae.
What They Look Like
• Fungi come in a variety of shapes and
sizes and different types. They can
range from single cells to enormous
chains of cells that can stretch for
miles.
• Yeast cells look round or oval under a
microscope. They're bigger than
bacteria, but still too small for your eyes
to see them individually.
Draw and label this
fungus cell

3. Fungi 3Where They’re Found
• Fungi usually grow best in places that are
slightly acidic. Fungi live in the soil and on
your body, in your house and on plants and
animals, in freshwater and seawater.
• A single teaspoon of soil contains about
120,000 fungus cells!
Whoa! The mould on this bread is
really out of control!
• If you ever get athlete’s foot (a skin
complaint that gives you itchy feet), then
you’ve got a fungus growing on you! (Don’t
worry, it’s not serious, and you can buy an
ointment that kills the fungus.) The
fungus likes moisture, so drying between
your toes helps to keep it away.

4. Fungi Extras
Read at your own risk – this may shock you!
The Humongous Fungus (definitely not a microbe!)
• Fungi range in size from the microbe we
call yeast to the largest known living
organism on Earth — a 3.5-mile-wide
fungus.
• Nicknamed ‘the humongous fungus’, this
honey mushroom covers 2,200 acres in the
state of Oregon, in the USA.
• The only above-ground signs of the
humongous fungus are patches of dead
trees (which the fungus has killed by eating
them), and the mushrooms (the ‘fruits’ of
the fungus) that form at the base of
infected trees.
• It started out 2,400 years ago as a single
spore invisible to the naked eye. It slowly
grew to immense size by growing long
threads of cells called hyphae, under the
ground.
Threads called
hyphae grow and
spread
underground