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FIND OUT MORE. Microorganisms 85 • Reproduction 101

86 Nature

Fungi

Neither plants nor animals, the fungi kingdom includes

toadstools, puffballs, and some. MOULDS. Fungi feed on

living or dead organisms by making them rot. Fungi are

visible only when spore-bearing fruiting bodies form.

MOULDS

Fungi called moulds produce the woolly or

furry growths found on rotting foods, such

as bread and fruit. The growths are formed

by thread-like hyphae that grow upwards

and release spores from their tips. These

spores then sprout on other foods.

HOW DO FUNGI FEED?

Fungi absorb nutrients from plant or animal matter

around them, which may be living or dead. They

produce long, slender threads called hyphae that

spread through their food. The hyphae release

enzymes that break down the food into

substances that the fungi can easily absorb.

HOW DO FUNGI REPRODUCE?

Most fungi reproduce by releasing tiny

spores that then germinate (sprout) and

grow into a new fungus. The spores are

produced by, and released from, a fruiting

body that is visible above the ground.

Some fungi drop spores, which are blown

away by the wind. Others shoot them out in

an explosive burst.

IS MOULD USEFUL?

Some moulds are useful. Penicillium, for example, is a

common blue mould that grows on fruit. It produces

an antibiotic called penicillin, which is used to kill

bacteria that cause harmful diseases. Penicillium

moulds are also used to flavour some cheeses.

4 BREAD MOULD

Pin moulds grow on starchy foods, such as bread, in a mass of

grey hyphae with black tips that release spores. The spores float

to other pieces of bread. Unseen here are hyphae growing into

the bread and absorbing its nutrients.

PENICILLIN TABLETS 3

This dish shows bacteria growing

on agar jelly. The white tablets

contain penicillin. Clear areas

around the tablets show

where penicillin has killed

some of the bacteria.

DON’T EAT! 3

The bright red colour

of these fly agaric

toadstool caps warns

animals that they are

poisonous. The caps, which are

supported by stalks, produce

spores. These spores are released

from downward-hanging

plates, or gills.

ARE MUSHROOMS AND TOADSTOOLS THE SAME?

Toadstools are brightly coloured and poisonous to eat,

but mushrooms are usually edible and dull in colour.

Both toadstools and mushrooms are fruiting bodies

(spore-bearing structures) produced by fungi. They

belong to the same group, the Basidiomycetes, so

scientists make no distinction between the two.

FUNGI CLASSIFICATION

Scientists are continually

revising the classification of the

fungi kingdom (with more than

100,000 species), but currently

they divide it into three groups:

• Pin moulds (Zygomycota);
  
  
  • Yeasts, moulds, morels, and
    truffles (Ascomycota, or spore
    shooters);
  
  
  • Smuts, rusts, jellies, mushrooms,
    and brackets (Basidiomycota, or
    spore droppers).
  
  
  
  

1 BUDDING YEAST CELLS

Yeasts reproduce by budding.

New cells grow out like bubbles

from parent cells, then separate.

1 PUFFBALL

When the puffball is mature, a

hole forms in the top. The slightest

knock then causes the puffball to

shoot clouds of spores into the air.

fungi