Good Science Victorian Curriculum Year 7

CHAPTER 2: CLASSIFICATION
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Living things are classified by
their characteristics
Biologists classify living things. The science of grouping living things
is called taxonomy, and a biologist who specialises in classification
is a taxonomist.
Millions of different types of organisms live on Earth. All living things:
• are made of cells
• are made of molecules containing carbon
• have biological characteristics in common, such as being able
to grow, move, reproduce and respond to stimuli.
Many other characteristics are shared by only some organisms.
Plants and animals have very different characteristics, of course,
but the differences between types of animal are also very significant.
Consider the differences between dogs and octopuses!
What is the name of the science of grouping living things?
The importance of classification
One of the most important reasons to classify living organisms is to work
out what relationships exist between different groups. Is a cat closely
related to a tiger? They have similarities, but also some very significant
differences. Classification systems help biologists learn how these
two animals, or any other two living things, are related.
A classification system helps biologists identify newly discovered
organisms. These discoveries happen more often than you might think –
the more we explore the world, the more new organisms we find. Many of
these, such as bacteria, are tiny – but new plants, insects, fish and other
animals are also discovered every year.
A classification system helps biologists from different countries
to communicate. An Australian wildlife scientist may use different
everyday names for trees and plants than a Chinese, French or
Indonesian scientist, but if they use the same classification system,
they can identify the organism more easily.
What are the benefits of classifying living things?
Figure 2.2
The ninja
lanternshark is a
small shark with
body parts that
glow in the dark.
It lives deep in the
ocean and was
not discovered by
scientists until 2015.
Investigation 2.1
Observing and
classifying
KEY SKILL
Writing a research
question
Go to page 142
CHECKPOINT 2.1
1 Describe classification in your
own words.
2 Give at least three reasons
for classifying living things.
3 Explain what is meant by the
term taxonomy.
4 Identify four situations where
things are classified in
everyday life.
5 Classify the following objects
into three groups: an apple,
a car, a fish, a basketball,
a mobile phone and a drop
of blood. Justify your choice
of classification.
6 Give some characteristics
of living things.
7 Classification can help identify
which species are closely
related. Suggest how.
INQUIRY
8 When we classify living
things, the first two categories
that usually come to mind
are plants and animals.
Brainstorm with a partner to try
to identify other categories of
living things.
SUCCESS CRITERIA
I can describe what
classification is.
I can explain three reasons
why classification is useful.
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