Ventillation And Gas Exchange In Insects Flashcards
How do insects prevent water loss
Lipid layer to prevent water loss
How do insects stay protected
They have an exoskeleton made of hard fibrous material
3 adaptations of insects to prevent water loss
1: small surface area to volume ratio where water can evaporate from
2: waterproof exoskeleton
3: spiracles where gas enters and water evaporates from, can open and close
What is the trachea
Network of internal tubes
They have rings within them to strengthen the tubes and keep them open
What are the tracheoles
The trachea branches into smaller tubes called tracheoles
They deliver oxygen to respiring cells
State 3 methods of moving gases within the tracheal system
- diffusion
- mass transport
- anaerobically respire
Describe gas exchange by diffusion
When cells respire they use of oxygen and produce carbon dioxide
Creating a concentration gradient from the tracheoles to the atmosphere
Describe gas exchange by mass transport
An insect contracts and relaxes their abdominal muscles to move gases on mass
Describe how insects respire anarobically for gas exchange
When the insect is in flight it respires anaerobically to produce lactate
This lowers the water potential of the cells so water moves from the tracheoles into the cells by osmosis
This decreases the volume of water in the tracheoles so more air from the atmosphere is drawn in
3 adaptations for efficient diffusion in insects
1: large number of fine tracheoles for a large surface area
2: walls of tracheoles are thin and there’s a short distance between spricales and tracheoles for a short diffusion pathway
3: use of oxygen and production of carbon dioxide sets up steep diffusion gradient
Describe ventilation in insects
Muscles contract to force air out
Pressure increases
Muscles relax and air moves out due to low pressure
