Describe the structure and function of the trochophore larva and name two groups that possess this larval stage.
A trochophore larva is characterized by a ring of cilia used for swimming and feeding. This larval stage is found in mollusks and annelids.
How do flatworms (Platyhelminthes) differ from other lophotrochozoans in terms of body cavity and digestive system?
Flatworms are acoelomates, meaning they lack a true body cavity, and have a rudimentary digestive system with only one opening (the mouth), through which both ingestion and egestion occur.
What is parthenogenesis, and which lophotrochozoan group commonly uses this reproductive strategy?
Parthenogenesis is a form of asexual reproduction where females produce offspring from unfertilized eggs. Rotifers commonly use parthenogenesis.
What is the main structural feature of a trochophore larva, and what is its function?
A trochophore larva has a ring of cilia used for swimming and feeding. The cilia help the larva move and bring food toward its mouth.
Name two groups of lophotrochozoans that possess the trochophore larval stage.
Mollusks and annelids both have a trochophore larval stage.
How do flatworms (Platyhelminthes) differ from other lophotrochozoans in terms of body cavity?
Flatworms are acoelomates, meaning they lack a true body cavity. Most other lophotrochozoans are coelomates or pseudocoelomates.
Describe the digestive system of flatworms and how it differs from that of other lophotrochozoans.
Flatworms have a rudimentary digestive system with only one opening, the mouth, for both ingestion and egestion. Other lophotrochozoans typically have a complete digestive tract with both a mouth and an anus.
What is parthenogenesis, and which lophotrochozoan group commonly uses this reproductive strategy?
Parthenogenesis is a form of asexual reproduction where females produce offspring from unfertilized eggs. Rotifers commonly use parthenogenesis.
What is the function of the lophophore in lophophorate animals?
The lophophore is a specialized feeding structure used for suspension feeding. It consists of ciliated tentacles that capture food particles from the water.
What are the three main body parts found in mollusks, and what is the function of each?
Mollusks have a foot for movement, a visceral mass containing internal organs, and a mantle that often secretes a shell. The mantle also forms a cavity housing the gills and anus.