Unit 3 - Gas exchange and ventilation in bony fish and insects Flashcards
As organisms get larger, what happens to the size of the diffusion distance?
It increases
As organisms get larger, what happens to the size of the surface area?
It increases
As organisms get larger, what happens to the size of volume?
It increases
As organisms get larger, what happens to the size of the SA:V?
It decreases
Why do more active organisms have a greater demand for Oxygen and Glucose?
-more energy is required for more movement
-more ATP must be produced
-more aerobic respiration must occur
-more reactants (glucose and oxygen) is required
What are the 4 features of efficient exchange surfaces?
-increased SA
-thin layers
-good blood supply
-ventilation to maintain diffusion gradient (for gaseous diffusion)
Why does an increased surface area make an exchange surface more efficient?
Provides the area needed for exchange surface to overcome the limitations of low SA:V ratio
Why do thin layers make an exchange surface more efficient?
The distances that substances have to diffuse across are shorter making diffusion quicker
Why does a good supply make an exchange surface more efficient?
The greater the difference in concentration the greater the rate of diffusion, a good blood supply means substances are constantly being delivered and removed, maintaining the steep concentration gradient
Why does ventilation increase the efficiency of a gas exchange surface?
Helps to maintain a steep concentration gradient
Respiratory organ in fish?
Gills
Respiratory organ in insects?
Tracheal
How does air enter body in insects?
Via spiracles
How are gases transported to/from the respiratory surface in fish?
Blood capillaries
How are gases transported to/from the respiratory surface in insects?
Tracheoles
