Gas Exchange In Fish And Insects Flashcards
What is in a fishes gills?
2 rows of fill ligaments that are connected to a bony arch
How many gills do bony fish have?
5
What are the gills covered by?
A bony plate called an operculum
How are the filaments adapted for gas exchange?
They are very thin and are folded into many secondary lamellae for a large surface area.
The blood capillaries are close to the secondary lamellae for quick gas exchange
What is countercurrent flow?
Blood flows the opposite was as the water in the lamellae for a high diffusion gradient so the most oxygen is absorbed
How are fish ventilated?
The buccal cavity can change volume. If the floor of the mouth goes down it draws in water to the buccal cavity.
The mouth closes and the floor raises again so the water goes through the gills.
How are the operculum and buccal cavity connected?
As the water is pushed into the buccal cavity, the operculum moves outwards.
This reduces the pressure in the operculum cavity to help the water into the gills.
How do insects transport oxygen?
Not in the blood. They have an open circulatory system that can be both blood and tissue fluid.
It can be affected by the insects body movements
How does air go around an insect?
They have a tracheal system so that the air goes directly to the reprising tissue
What happens at a spiracle?
They are little pores at the end of the segments that go into the tracheae
What are tracheoles?
The spiracles divide into tracheoles and could have some gas exchange
What is at the ends of the tracheoles?
Tracheal fluid
What happens in the tracjeole and tracheal fluid?
Gas exchange occurs
What happens when an insect is active?
The tracheal fluid is withdrawn to increase surface area to increase how much the insect can diffuse more in
How are insects ventilated sign the tracheal system?
The tracheal systems expand and have flexible walls. These act as air sacs that can be squeezed by the flight muscles. The expansion and contraction of these sacs ventilate the tracheal system
