Page 57 - ICSE Science 3 : E-book
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QUICK LOOK
1. Insects can adjust easily to the environment and are found almost everywhere on
the earth.
2. Insects lack bones on their body. They have a hard outer covering made up of
chitin.
3. The body of an insect is divided into three main parts—head, thorax and abdomen.
4. The head consists of two antennae, two compound eyes and mouthparts.
5. The thorax usually has wings and three pairs of legs.
6. The abdomen contains the digestive system, excretory system and reproductive
system.
7. A butterfl y has four stages in its life cycle—an egg, caterpillar, pupa and an adult
butterfl y.
8. Some insects are social and they live together in large colonies. Examples include
ants, bees and termites.
9. Insects may be useful or harmful to us.
10. We can get rid of their harmful eff ects by using chemicals called insecticides or
pesticides or by using natural methods.
EXERCISES
A. Fill in the blanks.
1. Insects have ______________ eyes which are made up of several smaller
eye units.
2. The tips of an insect’s feet usually contain ____________, ____________
or suckers.
3. The series of changes through which a living thing passes during its
lifetime is called its ______________.
4. ______________ help in keeping the number of mosquitoes under
control.
5. Insects do not have ______________.
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