Bivalves Flashcards
What phylum and class do they belong to
Mollusca
Bivalvia
When did they evolve and are there around today
Cambrian
Yes
What dies articulated mean
The valves are joined together but can move along the hinge lines
What does disarticulated mean
The valves are no longer joined together
What does equivalve mean
Valves of the same size
What does inequivalve mean
Valves of different size
What are siphons
Soft tissue that take in fresh water and filter it and removed used water
Where are most bivalves symmetry
Along the hinge line
How do you know if a bivalve is left or right (sinistral or dextral)
The direction of the umbone
Where is the umbone
It sits directly above the hinge line
What does the hinge itself consist of and rowdies it work
Protruding teeth and sunken pit-like sockets
These articulate against one another when the valves open and close, keeping the structure stable
On the outside f the shell, where the valves are joined what is there and what covers the area
Hinge plate
A ligament covers the area but decays in death
Where is the shell secreted
Mantle (part of the soft tissue inside the bivalve
What marks the position of the soft tissue
Palatial line on the inside of the shell
Finding it hard to remember the differences between Bivalves and Brachiopods?
Got to page 245 in the Geology OCR AS/A2 text book
What is the byssus
A group of thread-like structures made of a protein called collagen
What is a byssal notch
A shallow indentation or hole, which means the byssus does not interfere with opening and closing of the valves
What is cement
The calcareous substance secreted by the mantle and attaches the left valve to the substrate
What did they use to feed
Inhalant and exhalant siphons
What do the inhalant and exhaling siphons do
Inhalant-bring’s in fresh water
Exhalant-remove waste water
What removes particles from the water
The gills
