When insects inhale, air is drawn in through spiracles which are paired openings/pores located externally along the thorax and abdomen of the insect. These spiracles are lined with hairs that filter air entering the system to prevent airway obstruction and reduction of surface area available for gas exchange. Spiracles also help minimize water loss from hairs that trap moist air and valves that help control opening and closing. Since insects are terrestrial organisms that can be subject to desiccation, and therefore loss of water through evaporation, closing their spiracles may allow them to help conserve water and ensure that the gas exchange surface is kept moist ( because respiratory gases dissolve and spread into the environment). muscle fibers). However, the closure of the spiracles may also mean that oxygen-rich airflow is limited and therefore the efficiency of gas exchange would decrease, consequently affecting the rate of cellular respiration and the energy production needed to meet metabolic demands. of an insect. Air then travels from the spiracles into the internal tracheae/tracheal tubes which are supported by rings or bands of chitin (a strong, lightweight material) that help strengthen and provide flexibility to its structure. This ensures that the tracheae are kept open instead of being compressed during vigorous body movements and that the gas exchange surface is still sufficiently ventilated with the necessary oxygen to provide the large amounts of energy needed for such body movements, in particularly the flight when trying to escape. predation. Since there are numerous tracheal tubes that further branch into tiny tracheoles, the surface area to volume ratio increases so that maximum oxygen uptake can occur. Tracheoles are tiny tubes that end in a fluid-filled tip in which respiratory gases are soluble to allow diffusion of oxygen from highly oxygenated air