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BIO2135 – Animal Form and Function

Phylum Mollusca●Miller and Harley Chap. 11

BIO2135 – Animal Form and Function

Mollusca Phylogeny

Fig. 11.1

BIO2135 – Animal Form and Function

Lophotrochozoa PhylogenyFlat bodies

Platyzoa

Lophozoa

Trochozoa

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BIO2135 – Animal Form and Function

Mollusca Taxonomy● Class Caudofoveata (150 sp.)

– Wormlike marine burrowers● Class Solenogastres (250 sp.)

– Wormlike marine surface dwellers

● Class Polyplacophora (950 sp.)– Flattened with dorsal segmented shell

● Class Monoplacophora (25 sp.)– Flattened with dorsal complete shell

● Class Gastropoda (35 000 sp.)– Coiled shell on a distorted body

● Class Cephalopoda (550 sp.)– Elongated body with tentacles and siphon

● Class Bivalvia (30 000 sp.)– Filter feeders in a hinged shell case

● Class Scaphopoda (300 sp.)– Elongated body in a tube shell

BIO2135 – Animal Form and Function

Mollusca Body PlanFig. 11.2

BIO2135 – Animal Form and Function

Mantle and Shell

Fig. 11.3

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BIO2135 – Animal Form and Function

Radula

Fig. 11.4

BIO2135 – Animal Form and Function

Gastropod Torsion

Fig. 11.5

BIO2135 – Animal Form and Function

Shell Spiralling

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BIO2135 – Animal Form and Function

Gastropod Anatomy

Fig. 11.6

BIO2135 – Animal Form and Function

Gastropod Copulation

BIO2135 – Animal Form and Function

Gastropod Respiration

Fig. 26.14

Fig. 11.7c

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BIO2135 – Animal Form and Function

Bivalve Anatomy

Fig. 11.8 & 11.11

BIO2135 – Animal Form and Function

Bivalvia Burrowing

BIO2135 – Animal Form and Function

Bivalvia Burrowing

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BIO2135 – Animal Form and Function

Bivalve Feeding and Respiration

Fig. 11.9

& 11.10

BIO2135 – Animal Form and Function

Bivalve Circulation

Fig. 11.12

BIO2135 – Animal Form and Function

Bivalve Reproduction

Fig. 11.13 & 11.14

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BIO2135 – Animal Form and Function

Larval Stages

Fig. 10.2 & 11.13

BIO2135 – Animal Form and Function

CephalopodAnatomy

Fig. 11.13

BIO2135 – Animal Form and Function

Cephalopod Nervous System

Fig. 24.7 & 24.15

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BIO2135 – Animal Form and Function

Cephalopoda Feeding

BIO2135 – Animal Form and Function

Cephalopod Locomotion

BIO2135 – Animal Form and Function

Cephalopod

•Chromatophores•Photophores

• Ink

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BIO2135 – Animal Form and Function

Cryptic Camouflage

BIO2135 – Animal Form and Function

Next Class- Annelida● Miller and Harley Chap. 12