Molluscs Flashcards
1
Q
Are molluscs with Spiralians or Ecdyozoans?
A
SPIRALIANS!
2
Q
What are the eight living classes of Molluscs?
A
- Solenogastres
- Caudofoveata
- Polyplacophora
- Monoplacophora
- Bivalvia
6 Scaphopoda - Gastropoda
- Cephalopoda
3
Q
What are the apomorphies of Molluscs?
A
- Dorsal mantle with secreted chitin cuticle and calcareous spicules
- Radula
- foot and paired pedal retractor muscles
- bipectinate gills
- Tetraneural nervous system
- pair pedal nerve cord and pair of visceral nerve cord
4
Q
APLACOPHORA: apomorphies? (phallic looking worm tbh) (3)
A
- Cylindrical vermiform body (meaning it KINDA looks like a worm)
- no foot. instead has pedal groove
- has mantle with cuticle and calcerous spicules.
5
Q
What classes are within aplacophora?
A
Solenogastes and Caudofoveata
6
Q
POLYPLACOPHORA: apomorphies? (turtle shell looking things)
A
- has 8 dorsal overlapping valves,
- valve have tegmentum and articulamentum layers (something to do with neural stuff)
- They have sense organs embedded in the tegmentum of each valve
7
Q
advantages of the argonite-based lenses of polyplacophorans? (2 - re: dundancy)
A
- Having mutiple eyes creates redundancy, helps to reduce impacts of broken eyes.
- Redundancy also helps to organism to see wider view of its hemisphere for danger
8
Q
CONCHIFERA: apomorphies
A
- One piece of shell ith periostracum and calcareous layers
- Mantle margins with 3 folds
- Crystalline style - stiff mass in stomach and style sack of digestive enzymes
- No mantle spicules
- 8 pairs of dorsoventral pedal retractor muscles
9
Q
GASTROPODA! SNAILS! Apomorphies? (5)
A
- Torsion
- coiled asymetrical
- Anterior mantle cavity
- Operculum
- Left gonad lost
10
Q
BIVALVIA! apomorphies?
A
- Bivalve
- Adductor muscles
- lost radula
- suspension feeders
- inhalant and exhalant siphons
- relatively long-lived
