The Lophotrochozoa Flashcards
What are the phyla within the lophotrochozoa?
- Annelids
- Platyhelmithes
- Molluscs
Describe the body plan of annelids.
- Veriform (worm shaped)
- Large Coelom
- C and L muscles
- Segmented
- Septa
- VNC
- Water permeable skin
What are the three main classes of Annelids
- Polychaeta (Paraphyletic)
Ragworm
Lugworm
Fanworms - Oligochaeta (may be monophyly)
earthworms
-Hirudinea
Leeches
What is a coelom?
Fluid filled body cavity lines with a epithelial cell layer
What are septa?
Body wall divisions in layers of tissue
- splits up the coelom
What are parapodia?
Muscular perturtions from the sides of errant polychaetes that aid in movement
What is peristalsis?
- Increasing and decreasing of perimeter of sedentary polychaetes and oligochaetes
- aids in burrowing
C contract and L relax → smaller perimeter
C relax and L contract → larger perimeter
What does dioecious mean?
Having separate male and female individuals.
What is the reproductive structure in oligochaetes?
Clitellum
What is the main feeding mechanism of Hiridinea?
Blood-sucking ectoparasites.
What are the main features of Platyhelminthes?
- Three germ layers
- Bilaterial symmetry
- Centralised nervous system (with ‘brian’)
- no coelom
- no anus
- no repiritory organs
- no blood system
What are the main classes of Platyhelminthes?
- Planarians (freshwater flatworms)
- Polyclads (marine flatworms)
- Monogeneans (flukes)
- Trematodes (flukes)
- Cestodes (tapeworms)
Which Platyhelminthes are free-living and which are parasitic
Free-living:
- Planarians
- Polyclads
Parasites:
- Monogeneans (1 host, ecto)
- Trematodes (<1 hosts, endo)
- Cestodes (endo)
What are the main classes of Molluscs?
- Gastropods
- Bivalves
- Cephalopods
What is the basic body plan of a Molluscs?
- Through-gut
- Not segmented
- Shell and mantles
(shell secreted by mantle) - Gills
- Radula
(with odontophore)
