Insects are part of an animal group known as 'arthropods'. Arthropods are known as such in that
they utilize hard protective exterior cases known as an 'exoskeleton'.
Arthropods contain a host of well-known multi-legged creatures
including arachnids (spiders), millipedes and crustaceans
(ocean lobsters and crabs).
This exoskeleton makes up the entire surface
of the insect's body, put together by separate plates meeting
the joints of the body and legs. Arthropods do have muscles
within the exoskeleton, but the muscles attach to the exoskeleton
itself (as opposed to muscles attaching to ligaments and tendons,
which attach themselves to bones in a human body. Movement
is accomplished through these moving muscles, which in turn,
move the plated exoskeleton parts. Exoskeletons are primarily made of a substance
known as 'chitin', which is comparable to our real-world plastic.
This substance is made to be "self-moistured" to prevent the
surface of the insect from drying out.
Basic Parts of an Insect
There a three basic parts to an insect - the head, thorax (the central portion of the body)
and abdomen (the ball typically seen on many insects).
The head of an insect is where the main receptor parts are located.
Typically, you will find the eyes, mouthparts constituting
the mouth and biting parts (which also serve to guide food
into the mouth), and a pair of antennae, which are sensory
organs that allow the insect to use it's smell, taste, touch
and 'hearing' abilities. The head of the insect is the most
powerful part of it's body and is built from several connecting
plates. The eyes of an insect are known as 'compound
eyes' meaning that they are made up of several smaller
eyes functioning in unison.
The thorax, or mid-section, typically
holds the wings (if the insect can fly), usually two pairs
(for a total of 4 wings) and 3 sets of legs (for a total
of 6 legs). The thorax is also the central location of the
more powerful muscles used in operating the wings and legs
of the insect. The wings of most insects are setup with
a support structure of thickened veins. The pattern of these
veins varies from insect to insect. The feet-tips of insects
will usually contain sticky pads, hooks or suckers of some
type which allow the inset to cling to various types of
surfaces or to clasp on to it's prey.
The abdomen makes up the last, and
probably the most recognizable, part of the insect. This
section of the body stores the bug's digestive system, reproductive
organs and sting organs (if applicable). The abdomen is
a reactive part of the insect body, meaning that it can
expand when the insect feeds.
The body of an insect is does not mature like
the body of a human does. The body of an insect must 'molt'
or shed it's skin in an effort to grow. Once the insect has
shed it's old skin, it then takes in air or water into it's
new skin to 'blow' it up to it's new size. This must be done
before the exoskeleton hardens once more, or else the insect
will not grow into it's new larger size. Some insects have
been know to molt over 20 times in their lifetime, but this
process ceases when the insect has reached maturity in it's
adult stage. |