The need for gas exchange surfaces

Question 1

Why is gas exchange important?

Answer 1

• Living things need oxygen for respiration
• Its how gases mover between an organism and its environment

Question 2

Whats makes a good gas exchange surface?

Answer 2

• Large SA
• Short distance of diffusion
• Moist surface (dissolve in water which helps them move across membrane)
• Good blood supply (maintain concentration gradient)

Question 3

Single circulation of a fish

Answer 3

gill capillaries (blood is oxygenated)
aorta
systematic capillaries (blood is deoxygenated)
atrium -> ventricle