AS Gas Exchage Flashcards
What is the definition of Surface Area?
What is the definition of Volume?
The definition of Surface area is the size of organism surface.
The definition of Volume is the distance from surface to centre of the organism
How does Gas exchange occur in Single celled organisms?
Single celled organism carry out gas exchange across body surface due to large SA:V
What is present in insects that allows gas exchange?
What is gradient of gas exchange?
Insects have a tracheal system is where gas exchange occurs.
Tracheal system has trachea and tracheoles
Gas exchange happens through diffusion CO2 gradient from Tracheoles to atmosphere
What is the advantage of Spiracles in insects?
1.Spiracles:Oxygen enters and CO2 diffuse out.
What is an adaptation of insects when they are in flight?
In insects when they are in flight muscle cells respire anaerobically to produce Lactate lowers water potential so water moves from
Tracheoles into cells so more air drawn in due to decreased volume in tracheoles
Where does Gas Exchange occur in fish?
In fish gas exchange happens through the gills.
What three adaptations of gills present in fish?
Gill Filaments which are at a right angle to each other which gives it a large Surface Area which increase the rate of diffusion of oxygen from water into blood.
Gills filaments have Lamellae: Lamellae are folded so large Surface so increasing diffusion of oxygen from water into blood .
Lamellae and Gill Filaments are thin which increase diffusion rate.
What is counter current exchange in fish?
What does counter current exchange ensure?
Counter current exchange is when blood and water flow in opposite directions.
Counter current exchange ensures a favourable concentration of Oxygen is maintained across the whole length of the Lamellae
Where does Gas Exchange carried out in plant?
Gas exchange is carried out through Stomata.
Guard Cells Control opening and closing of stomata which is an advantage as it prevent water loss by evaporation.
What is the 4 adaptation of plants in gas exchange?
Leaves have small Surface Area:Volume.
Waxy cuticle thick
Hairy Leaves
Cuticle Rolls to cover stomata
How is leaves having Small SA:V advantageous?
Reducing water loss by evaporation
How is waxy cuticle thick advantageous in plants?
Waterproof covering
How is hairy leaves advantageous in plant gas exchange?
Traps water Vapour which reduces water potential gradient.
How is Cuticle Rolls advantageous in plant gas exchange?
Reduces water potential and less water lost by evaporation
