Insects

• Why can’t gas exchange happen

  They have a thick exoskeleton
• Where are the spiracles located

  Along the thorax/ abdomen of most insects
• What is the purpose of the spiracles

  Air enter and leaves through them
• What happens to the spiracles when the insect is inactive

  They close
• what leads away from the spiracles

  the trachea
• What is the trachea lined with

  Spirals of chitin
• What do the spirals of chitin do

  Keeps the trachea open of bent or pressed
• What do the trachea branch to form

  The tracheoles
• what is at the end of the tracheoles

  Tracheole fluid
• What happens when oxygen demand builds up

  Lactic acid builds up resulting in water moving out of tracheoles
• Names two adaptions for larger insects with specialised bra tying mechanisms

  • air sacs on the tracheal system which can be squeezed by flight muscles
  • as the expand abdomen = open front spiracles close back spiracles. contract abdomen = open back spiracles, close front spiracles