Good Science Victorian Curriculum Year 7

BIOLOGICAL SCIENCES
2.6
CLASSIFYING
FUNGI
LEARNING INTENTION
At the end of this lesson I will
understand how scientists
classify fungi.
KEY TERMS
antibiotic
a substance that kills or slows
the growth of bacteria
decomposer
an organism that breaks down
and recycles decaying matter
parasite
an organism that gets nutrients
from the body of another
organism, causing it harm
symbiont
an organism that lives with
a host organism, and both
organisms benefit
LITERACY LINK
READING
Make a list of five words in this
lesson that a primary school
student might not understand,
then write a definition for each.
NUMERACY LINK
DATA
Jo found six mushrooms.
The three growing in sunlight
weighed 25 g, 28 g and 22 g,
while the three growing in shade
weighed 15 g, 35 g and 38 g.
What does this data show about
where mushrooms like to grow?
1
2
When he constructed his classification system, Carolus Linnaeus
only recognised two kingdoms: animals and plants. He thought
that organisms such as mushrooms and yeast were plants.
Since that time, scientists have classified these organisms
in their own category: kingdom Fungi.
Fungi are not the same as plants
Fungi are similar to plants in a number of ways. They can’t move around,
and they reproduce using spores. However, they are different from plants
in some important ways:
• Fungi can live in many different places, such as air, water, soil and on
plants and animals.
• Instead of roots, fungi have hair-like filaments that grow into whatever
they live upon.
• Fungi do not create their own food using photosynthesis.
One of the most important characteristics of fungi is how they receive
nourishment. They are decomposers, breaking down dead organisms
into simple compounds. Fungi do this using enzymes that break down
dead plant and animal matter from their surroundings. They then absorb
those nutrients through their filaments.
Some fungi are parasites that feed on living things. They harm the
organisms on which they live so that they can digest the damaged parts.
Other fungi are symbionts, and actually help the organisms on which they
live. A symbiont living on a plant’s roots will take sugar and oils from the
plant, but the plant gains useful minerals from the fungi when it decays.
What are the main characteristics of fungi?
Many fungi are part of our diets
There are more than 70 000 different species of fungi, and many of them
can be eaten. Mushrooms, truffles and morels are all edible. Mushrooms
are common in Australia and around the world, and they grow in many
different environments. Truffles and morels are rarer, and are often
considered an expensive delicacy. These fungi grow underground in close
relationships with the roots of trees such as oaks.
The fungus that has the biggest part in our diets is yeast. Yeasts are
microscopic fungi that feed on sugars and produce carbon dioxide.
Unlike most fungi, they are single-celled
organisms. They are used to bake bread,
because the carbon dioxide gas they produce
when they break down the bread flour makes
the dough rise. Yeasts are also used to break down
sugars in plants to produce some drinks.
How do yeasts cause bread to rise?
28 GOOD SCIENCE VICTORIAN CURRICULUM 7