Gas Exchange Flashcards
How do flatworms exchange gases?
Simple diffusion
Do flatworms have a permeable surface?
Yes
Do flatworms have haemoglobin?
No
Do earthworms have haemoglobin?
Yes
What has a larger surface area to volume ratio, the flatworm or the earthworm?
The flatworm
Does the earthworm have a high oxygen requirement?
No
What is the respiratory surface of the earthworm?
The skin
What do amphibians use for gas exchange?
Their skin and their lungs.
How would you describe the skin of an amphibian?
Moist and permeable
Do amphibians have a cardiovascular system?
Yes
How do fish inhale?
• The mouth opens
• The operculum closes
• The floor of the mouth cavity is lowered
• The volume of the mouth cavity increases and the pressure falls
• Water flows into the mouth
How do fish exhale?
• The mouth closes
• The operculum opens
• The floor of the mouth cavity is raised
• The volume of the mouth cavity decreases and the pressure increases
• Water flows out of the gills
What is the advantage of counter current flow?
The concentration gradient is maintained across the entire gill plate
What is counter current flow?
Blood and water flow in opposite directions, maintaining the concentration gradient.
