Ecdysozoans and Their Characteristics

Flashcards focusing on key vocabulary related to ecdysozoans, arthropods, and echinoderms.

Ecdysozoan

An animal that molts its exoskeleton as it grows.

Tagmata

Body segments in arthropods; each different regions like head, thorax, and abdomen.

Exoskeleton

A hard outer structure composed of chitin and protein that protects against water loss.

Ecdysis

The process of shedding the old exoskeleton.

Jointed Appendages

Limbs that may be modified for various functions, such as sensing or locomotion.

Open Circulatory System

A system in which the blood is not entirely contained within blood vessels.

Ommatidia

Independent visual units that make up compound eyes in arthropods.

Spiracles

Small holes that lead to trachea for breathing in terrestrial arthropods.

Malpighian Tubules

Structures in terrestrial arthropods that excrete waste and reabsorb water.

Chelicerata

A subphylum that includes spiders, ticks, mites, and horseshoe crabs.

Spinnerets

Appendages associated with spiders that produce silk for webs.

Crustacea

A class of arthropods that includes crabs, shrimp, and lobsters, characterized by having a cephalothorax.

Nauplius

A free-swimming larval stage of crustaceans before reaching maturity.

Decapods

Crustaceans that have 5 pairs of thoracic appendages and a reinforced exoskeleton.

Hexapoda

The largest group of animals on Earth, characterized by having three tagmata: head, thorax, abdomen.

Sensory setae

Hairlike structures that help detect sounds and communicate in insects.

Myriapods

A subphylum that includes centipedes and millipedes, characterized by many body segments.

Bilateral Symmetry

Symmetry where the body can be divided into two equal halves; seen in larval Echinodermata.

Water Vascular System

A network in echinoderms involved in locomotion and feeding.

Asteroidea

A class of Echinodermata that includes sea stars, which are important predators.

Echinoidea

A class that includes sea urchins and sand dollars; they lack arms and have spines.

Ophiuroidea

A class of brittle stars, characterized by their ability to autotomize arms for escape.