RESPIRATORY SYSTEM(TRACHEAL SYS.) Gas exchange Responsible for delivering oxygen and removing Co2 Insect blood doesn’t contain haemoglobin Has massive plumbing with tubes carry air to cells: TRACHEAL SYSTEM

SPIRACLE Located on the thorax and abdomen One pair of spiracle per segment Opening with muscles, allows air to enter minimize water loss Mechanism of opening and closing of spiracle muscle: Co2 high in body muscles relax  spircales open Co2 escape + Oxygen in when O2 in body approx. outside  muscles contract  spricales pull shut

Eg: muscles cells: tracheols enter deep into the cells: close to mitchondria (where o2 needed) GAS (outside)spiracles tracheal trunk (primary trachea) 2o & 3o trachea tracheole

AQUATIC ADAPTATION BIOLOGICAL GILLS mayflies and damselflies, the gills are leaf-like in shape and located on the sides or rear of the abdomen.  Stoneflies and caddisflies have filamentous gills on the thorax or abdomen.  Dragonflies differ from other aquatic insects by having internal gills associated with the rectum.

Breathing Tubes Snorkel-like a tube with spiracles- the tube above water for air intake Water bubble (DIVING BEETLE) carry a bubble of air with them whenever they dive beneath the water surface