Lophotrochozoans: Structure, Function, and Diversity

Lophotrochozoans

A group of protostome animals with diverse forms.

Triploblastic

Organisms with three germ layers: ectoderm, mesoderm, endoderm.

Cephalization

Concentration of sensory organs in the head.

Protosomes

Animals where mouth develops first from ectoderm.

Deuterosomes

Animals where mouth develops second from ectoderm.

Protosomy

Developmental process where mouth forms first.

Lophophore

Ciliated feeding structure surrounding the mouth.

Trochophore larvae

Free-swimming larvae with two cilia bands.

Acoelomates

Animals without a body cavity (coelom).

Pseudocoelomates

Animals with a cavity lined only by mesoderm.

Eucoelomates

Animals with a coelom lined by epithelial cells.

Coelom

Body cavity separating ectoderm from endoderm.

Platyhelminthes

Phylum of flatworms, including free-living and parasitic forms.

Gastrovascular cavity

Branching cavity for digestion and nutrient distribution.

Incomplete digestive system

Single opening serving as mouth and anus.

Extracellular digestion

Digestion occurring outside cells, using enzymes.

Flame cells

Cells regulating waste and salts, resembling kidneys.

Cerebral ganglia

Nerve clusters acting as a primitive brain.

Proglottids

Segments of tapeworms that contain reproductive structures.

Schistosomiasis

Waterborne disease caused by blood flukes.

Rotifers

Microscopic aquatic organisms with ciliated feeding structures.

Mastax

Pharynx structure in rotifers for food processing.

Rhynchocoel

Pocket containing proboscis for capturing prey.

External fertilization

Process where eggs and sperm are released into the environment.