Page 51 - ICSE Science 3 : E-book

Head
wings
thorax Insects have a pair of antennae, a pair of
head antennae
abdomen compound eyes and mouthparts on their head.
They use their antennae as sensory organs to
detect odours (smell), tastes, vibrations and
compound
eye sounds. They have compound eyes which are

legs made up of several smaller eye units. These help
Body parts of an insect the insects to keep track of fast moving things
around them.

The mouthparts of insects can be of diff erent types depending on the type of food
they eat. Many insects like grasshoppers and beetles have biting and chewing
type of mouthparts. Some others like butterfl ies and moths have siphoning type

of mouthparts adapted for sucking nectar from fl owers. Insects like mosquitoes

have a needle-like mouthpart. They use it to break through the tissues of animals
and plants to suck blood and plant juices, respectively. Ants have powerful jaws
that help them to dig and collect food.

Thorax

The middle portion of an insect’s body is known
as thorax. It is divided into three segments. It Did You Know!
Insects breathe through special
bears three pairs of legs, one on each segment.
openings called spiracles present
The legs are adapted to walk, swim, jump, dig on both sides of the body on

and grab. The tips of their feet usually contain thorax and abdomen. Their
number varies from
sticky pads, hooks or suckers which allow them species to species.

to cling to various types of surfaces or to hold
on to their prey.

The thorax also bears wings. Most insects have two pairs of wings, but a few like fl ies

have only one pair. Some insects like ants and fl eas do not have wings at all.

Abdomen

The abdomen usually consists of 11 segments. It contains the digestive system,

excretory system and reproductive system. It may also contain specialised organs
like stingers.

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