Draw a diagram to show the life-cycle of a
silk moth.

The female silk moth lays eggs. When the eggs hatch a tiny Caterpillar comes out, This is the Silkworm or Larva. The silkworm feeds on leaves and grass. When it is ready to enter the next stage in its lifecycle, it first weaves a net around itself. It then secrets a fibre made up of proteins which hardens on exposure to air. This is the Silk fibre. It covers itself completely with this fibre to form a cocoon at this stage the Larva is called Pupa. The Pupa grows and changes inside the cocoon. A few weeks later the cocoon opens and an adult moth come out.

━━━━━━━━━━━━━━━━━━━━

a and b sometimes have a positive value