Lecture 8 - Mollusca Flashcards
What are the 3 main classes of Mollusca?
- gastropoda
- cephalopoda
- bivalvia
Where is the colem located?
Around the heart
How do molluscs get their shell?
Minerals are abrsorbed through the mantle
What is the foot usually attatched to?
Head
What is the radula?
Ribbon-like teeth found in the head/mouth area
What are the main functions of the radula?
- scrapes food particles from hard surfaces
- conveyor belt to move food to stomach
Describe Mollusca’s circulatory system.
Open circulatory sytem, organs sit in blood, slow blood movement
What is the special name for gills in Mollusca?
ctenidia
What are the functions of ctenidia?
Respiration
What is the oldest part of the bivalve shell?
Umbo
Describe how pearls are produced.
An irritant is lodged between the shell and mantle and narce is secreted around irritant
Describe the general features of bivalves
- mostly marine, some freshwater
- no radula or head
- mostly filter feeders
What are siphons?
Two tube-like structures that bring water in and out of organism
What are the two types of siphons?
- incurrent: water/particles moves in
- excurrent: water/particles moves out
How do salt-water bivalves reproduce?
Gamates are released into the water and are fertilized externally
