Ventilation in other organisms

Question 1

What’s the name given to the system fish use?

Answer 1

counter current system

Question 2

Explain the counter current system?

Answer 2

blood flows one way in gill plates and water flows over in other direction. This maintains a steep concentration gradient of oxygen into the blood so that a much higher level of oxygen saturation of the blood is achieved

Question 3

How do fish get water to flow through their gills?

Answer 3

Open mouth and floor of buccal cavity lowers which increases the volume and decreases the pressure so that water flows in. Mouth shuts and floor is raised so that volume decreases and pressure increases. The increased pressure forces operculum open and water moves out over gills

Question 4

Why do the tips of gill filaments overlap?

Answer 4

to increase resistance against flow of water so that it flows slower therefore increasing the time for gaseous exchange.

Question 5

How do insects deliver oxygen to their cells?

Answer 5

directly delivered through holes in abdomen called spiracles which have tracheae connected that lead to trachioles which have permeable walls allowing oxygen to pass out directly into the cells

Question 6

How are spiracles controlled?

Answer 6

sphincters which can close to reduce water loss when oxygen isn’t in high demand