Ecdysozoans

Flashcards covering key vocabulary terms from the Ecdysozoa lecture.

Ecdysis

Molting of the cuticle to accommodate a growing animal.

Cuticle (in Ecdysozoans)

Non-living, secreted, tough exoskeleton made of collagen or chitin.

Nematoda

Phylum of roundworms, very abundant in many habitats, with about 28,000 identified species and potentially 500,000 species.

Pseudocoelomate

A body cavity that is not completely lined by mesoderm.

Nematode Cuticle

Outer, non-cellular, collagenous covering with three layers (cortex, matrix, basal) that maintains internal hydrostatic pressure and provides mechanical protection.

Amphids

Anterior depressions in the cuticle of nematodes that contain modified cilia and function in chemoreception.

Phasmids

Structures near the anus of nematodes that function in chemoreception.

Pseudocoelom (in Nematodes)

A spacious, fluid-filled cavity in nematodes that contains visceral organs and forms a hydrostatic skeleton.

Ascaris lumbricoides

Intestinal Roundworm of Humans

Enterobius vermicularis

Human Pinworm

Nectator americanus

New World Hookworm

Trichinella spiralis

Porkworm

Filarial Worms (Wuchereria sp.)

Human parasites that live in the lymphatic system and can cause Elephantiasis.

Dirofilaria immitis

Infects dogs in the US and causes Heartworm disease.

Phylum Nematomorpha

Horsehair worms; adults are free-living, juveniles are parasitic of arthropods, and they lack a digestive system.

Phylum Kinorhyncha

Minute worms living in marine habitats; burrow by moving the snout and using scalids to hold to the substrate.

Priapulida

Marine worms found in cold waters that live in marine sediment and feed on invertebrates and worms.

Loricifera

Live in the spaces between marine sand and gravel; have a spiny head (introvert), thorax, and abdomen (surrounded by cuticular lorica).