Page 188 - Biology_F5

Comparative studies of natural groups of organisms

Adaptations of millipede to its mode of Activity 3.12
life
Millipedes have the following features that
make them adapt to their environment:
(a) They have many, short and strong legs
that enable them to burrow into the
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soil.
(b) They produce special secretions, S 5
which help them to moisturise dead
organic matter on which they feed.

(c) A millipede tends to curl up into a tight
flat coil for self-defence, and protect
their delicate legs inside an armoured
exoskeleton.

(d) Millipedes produce an offensively
odorous fluid (repugnatorial fluid) S 6
when provoked, this acts as a defence
against predators.

Class Insecta
The class insecta contains all insects and
is the most diverse group of organisms on S
the earth. Members of this class are found 7
in all environments, including freshwater
aquatic and terrestrial environments, but Figure 3.52: Specimens S , S , and S 7
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very few are found in marine environment.
They differ in morphology and feeding Study specimen S , S , and S (Figure
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habits. Although members of this group 3.52) carefully, then answer the
vary greatly, they have some common questions that follow:
characteristics, which make them to 1. Identify specimens S , S , and S by
belong to the same class. Members of this their common names. 5 6 7
class have three pairs of walking legs,
three distinct body parts or regions and 2. Name the classes to which
one pair of antennae borne on the head. specimens S and S belong.
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The antennae are used as sense organs 3. List the observable features that
for detection of odour molecules in the have enabled you to place the two
air, changes in the concentration of water specimens in (2) above into their
vapour, sounds, and gauging air speed. respective classes.
Examples of insects include grasshopper,
butterfly, housefly, cockroach, beetle,
bees, ant, wasp, and termite.

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