Phylum Annelida Lecture Notes

This set of flashcards covers key concepts, characteristics, and features of the Phylum Annelida as discussed in the lecture notes.

What defines the Phylum Annelida?

Annelida is characterized by segmented worms, one or more pair of chitinous setae, and internal separation by septa.

What type of development do annelids undergo?

Annelids undergo protostome development.

What are the main body adaptations in Annelida?

Compartmentalization allows local deformation of the body wall without affecting hydrostatic pressure in other compartments.

What type of circulatory system do annelids have?

Annelids possess a closed circulatory system with contractile dorsal and ventral blood vessels.

How do annelids exchange gases?

Gas exchange occurs across the body surface and may also occur through gills or other specialized structures.

What are the primary features of Hirudinea?

Hirudinea, or leeches, have anterior and posterior suckers, few or absent chaetae, and may be predatory or parasitic.

What is unique about the reproductive strategy of Clitellata?

Clitellata exhibit hermaphroditism with permanent gonads and engage in reciprocal sperm exchange.

What are the characteristics of the Siboglinidae group?

Siboglinidae consists of tube-dwelling species with a gut absent and a symbiotic relationship with bacteria.

What is a key distinguishing feature of Echiura?

Echiura are characterized by a non-segmented body plan as adults, with a spoon-shaped proboscis.

How do Sipuncula differ from other annelids?

Sipuncula have a U-shaped gut, a large coelom, and do not have a circulatory system.