Many insects start life as soft-skinned grubs, or larvae, but
eventually they all turn into adults with hard, segmented
bodies and six jointed legs. Their skin is toughened with a
substance called chitin, which is rather like hard plastic, so
it acts as an external skeleton. It is often shiny and brightly
coloured, but it can look furry or scaly. Most adult insects
like this wasp also have wings made from sheets of chitin,
powered by muscles inside their bodies.Insect anatomy
(^1) ANTENNAE
An insect’s long antennae help it feel its
way, but they are mainly used to detect
scent. They are covered with sensitive
nerve endings that pick up chemical
signals. The antennae of some moths
can detect scents from more than a
kilometre (0.6 miles) away.
The sensory antennae
of this wasp enable it to
recognize food and other
members of its colony
eyes has just one lens that Each of the three simple
cannot form an imagecan sense light but
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(^3) EYES
Like many other insects, an adult
wasp has two large compound eyes.
Each has hundreds of tiny lenses
that see the world as a mosaic of
coloured dots. A wasp also has
three small simple eyes, which are
called ocelli, on the top of its head.
(^2) HEAD
An insect’s head contains its brain
and carries most of its sense organs.
It is also equipped with mouthparts
that are specialized to deal with its
diet. A mosquito has a sharp needle
for sucking blood, while this wasp has
stout jaws for chewing other insects.
(^4) THORAX
The legs and wings of an insect are
attached to the front section of its
body, the thorax. This is packed
with wing muscles, which power
the wings rather like someone in
a rowing boat using a pair of oars.
It also contains the insect’s crop,
used to store food.
Compound eyes give
the wasp quite good
vision, and are also very
sensitive to movement
HEAD THORAX
Long, jointed antennae
are vital sense organs
2
3
4
1
Fine, touch-sensitive
bristles on the insect’s
body detect vibrations
and air movements
The antenna of a female
wasp has 12 segments, while
the male antenna has 13
Mandibles, or mouth
parts, are used to slice
vegetation or prey
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