Gas Exchange In Insects Flashcards
What is the role of spiracles in gas exchange in insects
are small openings on the thorax of the insect through which air enters and leaves, as well as water.
They can be opened (during periods of high demand for oxygen) or closed (when the insect is inactive)
What is the role of trachea in gas exchange in insects
Tracheae are large tubes which lead off from spiracles, carrying air into the body.
They are lines with chitin to give them mechanical strength, but are impermeable so no gaseous exchange can take place
What is the role of Tracheoles in Insects- Gas Exchange
Tracheoles come off of tracheae branches and are single elongated cells which run between tissues.
What is the effect of tracheoles having no chitin
They have no chitin lining so are permeable allowing gaseous exchange.
What is the effect having lots of tracheoles
Lots of tracheoles give a large area for diffusion
What is the effect of tracheole having a moist lining
Moisture in tracheoles allows oxygen to diffuse into liquid before diffusing into tissues.
What is mechanical Ventilation
Air is actively pumped into the tracheal system.
The spiracles open and the insect makes muscular pumping movements of the thorax, abdomen or both
What is the effect of the ventilaiting movement
it changes the volume and therefore the pressure inside the body drawing air in and out of the tracheae and tracheoles
How have insects adapted to minimize water loss
Small SA:VOL ratio
Waterproof ekoskelton
Spiracles
What is the effect of tracheal fluid in gas exchange in insects
limits penetration of oxygen down tracheoles, reducing area available for diffusion
What happens when their is high levels of activity in a insect (tracheal fluid)
during periods of high activity the build up of lactic acid causes tracheal fluid to move out and expose more area for gaseous exchange,
What is the role of air sacs highly in active insects in insects
which act as reservoirs during times of high activity, but can be deflated.
What effect does air sacs have in active insects
increase the volume of air moved through the respiotary system
How does gas exchange occur in insects 1/3
Air enters the system through the spiracles. However some water is lost when the open so spiracle sphincters are kepy closed as much as possible
How does gas exchange occur in insects 2/3
Air moves along the trachea and tracheoles by diffusion. The network of tiny tracheous gives a large SA this is where gas exchange takes place
