Gas Exchange In Insects Flashcards
What insects can rely on diffusion alone?
-have to have a large surface area: volume ratio
-smaller animals
Why do insects have to conserve water?
-Have to create a moist surface for gas exchange so it can occur efficiently as they live on land.
What adaptations do insects have to counter water loss?
-water proof covering(exoskeleton) made of chitin with a waterproof cuticle.
-larger insects have a small surface area to volume ratio which minimises the area over water can be lost.
What is the order of a gas exchange system in an insect?
Spiricle ——> trachea ———> treacheoles.
What do the tracheoles do?
Deliver oxygen to respiring cells.
What is the spiricle?
A pore in the abdomen of an insect connected to the trachea which takes in gases.
What are some adaptions of the tracheoles?
-Have permeable walls ah I hate only one cell thick to create a short diffusion pathway.
-contain fluid at the end which the gas can dissolve in to make diffusion more efficient.
What are adaptions for the spiricles?
-have muscles which can open and close the spiricles to balance water loss.
-have gators inside spiricles to trap humid air.
Why do the spiricles contain hair inside?
To reduce water loss at it can increase the water potential gradient which we want to be as low as possible so less water vapour is lost by diffusion.
What is abdominal pumping?
When insects exercise vigorously they use muscles to pump the abdomen rapidly to take up more oxygen into the tracheoles.
Why do insects do abdominal pumping when exercising?
To maintain a steep diffusion gradient so more oxygen will diffuse in and more CO2 will diffuse out during exercise.
Why do some insects have ‘air sacs’ they can fill with gas?
So that if the environment is dry/ has a large water potential gradient they can keep the spiricles closed to prevent water loss.