Page 113 - Science

• Insects do not have bones inside of them, on the

outside are thick plates of armour to which the

muscles attach.

• The armour is an outside skeleton (exoskeleton).

• As human grow, their bones also grow.

• But exoskeleton does not grow, yet insects like

caterpillar increase in size.

• How do they do it?

• When an insect is ready to increase in size, its

body pushes on the exoskeleton and makes it split

and fall away.

• This is called moulting.

• Underneath is a softer armour which can be

stretch but hardens as it is exposed to the air.