Respiration Flashcards
What is the aim of aerobic respiration?
To obtain energy
What does diffusion rate in the lungs depend on?
Surface area of the respiratory surface
Thickness of respiratory surface
Metabolic demands (concentration gradient)
What transports gases around the body in insects?
Trachea
How is passive ventilation carried out in insects?
Air diffuses through spiracles
Enters the trachea
The trachea branch off into tracheoles
Oxygen is delivered directly to cells
How is active ventilation carried out in insects?
Trachea inflate and deflate to pump air through
Increase movement of air by rhythmic body movements (expansion and compression of trachea)
What is tidal ventilation?
Gases exit the same way they enter
What prevents water loss in insects?
Hard outer cuticle
How do hairs around spiracles trap water?
Increases humidity around spiracles to decrease diffusion gradient for water molecules
Why are insect’s air sacs useful?
Store air when environment is dry
When energy demands are high e.g. flying
What happens to haemoglobin when temperatures are low?
Happens in the lungs
Has a higher affinity for oxygen
So oxygen can bind more readily in the lungs
What does increasing pH do to oxygen and what is this called?
Less oxygen binds to haemoglobin
Bohr Effect
Does a foetus have a higher or lower affinity for oxygen?
Higher
What adaptations to fish have for respiration?
Short diffusion distance
Gills have a large surface area
Water flows in a single direction
Countercurrent flow
How is ventilation carried out in birds?
First inhalation = air enters the posterior air sacs
First exhalation = air forced into lungs for gas exchange
Second inhalation = air moves into anterior air sacs
Second exhalation = air pushed out of body
Is ventilation in birds tidal?
No, unidirectional
