Ventilation in fish and insects Flashcards
what is an operculum
a bony flap which protects gill
what is the buccal cavity
the mouth of a fish
what is the primary lamellae/ gill filaments
The gill filaments, branches of tissue which make up the gill
where are gills located on the fish
On the head
Describe the ventilation of a fish
Buccal cavity floor lowers, increasing cavity volume, decreasing cavity pressure.
Water enters due to pressure gradient
Floor raises
operculum moves outwards to reduce pressure in operculum cavity and allow water to travel to gills and exchange gases.
when the buccal cavity floor lowers, what happens to the pressure and volume of the cavity
Pressure decreases, volume increases
what is counter current flow
when the blood flow in the fills and secondary lamellae is flowing in an opposite direction to the flow of water to maximise oxygen absorption
what supports tracheae in insects
RIngs of chitin which prevent it from collapsing
what is the tracheal system
system of air filled tubes, which exchange gases with the tracheal fluid
How does air enter the tracheal system of insects
through a spiracle in the exoskeleton
in more active insects what can cause ventillation
Body movements
