Key Characteristics
*Mollusks are triploblastic coelomates with bilateral symmetry and cephalization
*Have four main body parts. The foot for movement, visceral mass that contains most of the internal organs, mantle which surrounds the visceral mass which secretes calcium carbonate (the shell).
*Have a free swimming larval stage called trochophore
*Can have an open or closed circulatory system
*There are about 50,000 species in this phylum
Habitat
Mollusca live in or near water. Some are freshwater such as mussels, others are saltwater like octopi.
Interesting Facts
1. Mollusks are the largest marine phylum, comprising about 23% of all the named marine organisms.
2. Some oysters alternate their gender, male one year, female the next
3. Octopi have the most developed eye of all invertebrates and can see in color
4. Squid have little or no sense of hearing
5. An unhatched baby octopus can squirt ink
*Mollusks are triploblastic coelomates with bilateral symmetry and cephalization
*Have four main body parts. The foot for movement, visceral mass that contains most of the internal organs, mantle which surrounds the visceral mass which secretes calcium carbonate (the shell).
*Have a free swimming larval stage called trochophore
*Can have an open or closed circulatory system
*There are about 50,000 species in this phylum
Habitat
Mollusca live in or near water. Some are freshwater such as mussels, others are saltwater like octopi.
Interesting Facts
1. Mollusks are the largest marine phylum, comprising about 23% of all the named marine organisms.
2. Some oysters alternate their gender, male one year, female the next
3. Octopi have the most developed eye of all invertebrates and can see in color
4. Squid have little or no sense of hearing
5. An unhatched baby octopus can squirt ink