3.1.5 gas exchange in other organisms (bony fish & insects) Flashcards
(fish) buccal cavity
mouth
(fish) countercurrent flow
2 fluids flow in opposite directions
(fish) describe filaments
- what can they also be called
slim branches of tissue that make up the gill
(primary lamellae)
(fish) describe lamellae
—> what can these also be called
folds of filament to increase surface area
—> often called secondary lamellae or gill plates
(fish) operculum
bony flap that covers/protects gills
(insect) spiracle
pore that allows air in/out of tracheae
(insect) tracheal fluid
fluid found at ends of tracheoles in tracheal system
(insect) tracheal system
system of air-filled tubes
how do bony fish exchange gases
using gills to absorb oxygen dissolved in water & release carbon dioxide into water
how many pairs of gills do most bony fish have
5
what does each gill consist of
2 rows of gill filaments attached to bony arch
describe the gill filaments
- very thin
- surface folded into many secondary lamellae (gill plates) = large surface area
how does exchange occur in bony fish
capillaries carry deoxygenated blood close to surface of secondary lamellae
describe the dissection of a fish gill
- find operculum
- lift operculum to observe gills/colour
- cut away one operculum
- cut out one gill
describe the countercurrent flow in bony fish
- blood flows along gill arch & along filaments to secondary lamellae
- then blood flows through capillaries in opposite direction to flow of water over the lamellae