Arthropods and Echinoderms

An arthropods hind section, it contains reproductive and digestive organs. Abdomen. In simple terms, the abdomen is the part of an animal's body where digestion and reproduction happen.

A structure that grows out of the body of an arthropod, like a leg or wing. Appendage. In Science, an appendage is a body part that extends from the main body, such as a leg, wing, or antenna.

An arthropods respiratory organ, with folded walls arranged like pages in a book. Book lung. A book lung is a breathing organ in some arachnids, like spiders, that looks like stacked pages and helps them exchange gases with the environment.

The shell of a turtle or tortoise, or the plate that covers the head of a crustacean. Carapace. In science, a carapace is a hard protective outer covering found on certain animals, like turtles and crustaceans.

A group of individuals in an insect society that performs specialized tasks. Caste. In science, a caste is a group within a social species that has a specific role, such as workers or soldiers in ants or bees.

A fused head and thorax found in some arthropods. Cephalothorax. In some arthropods like spiders and crabs, the cephalothorax is a body part where the head and chest are combined into one section.

One of a pair of appendages that act as pincers or fangs, in Chelicerata like sea spiders. Chelicerae are mouthparts used for feeding or defense in certain arthropods, like spiders and scorpions.

Metamorphosis with 4 stages, where the young and the adults look very different. Complete metamorphosis. Complete metamorphosis is when an insect undergoes four distinct stages egg, larva, pupa, and adult, each looking different from the others.

Metamorphosis with 3 stages, where the young and the adults look alike. Incomplete metamorphosis. Incomplete metamorphosis is when an insect changes form in three stages egg, nymph, and adult, and the young nymphs resemble the adults.

Sieve-like structure that filters particles from an echinoderms water vascular system. Madreporite. The madreporite is a small, porous plate on the surface of echinoderms that acts like a filter to manage water flow into their water vascular system.

An excretory tube located in the abdomen of most insects and arthropods. Malpighian tubule. Malpighian tubules help insects remove waste from their bodies by filtering out unwanted substances from their blood.

A fused head and thorax found in some arthropods the mouthpart adapted for biting and chewing food, in most arthropods. Mandible. A mandible is the jaw or jawbone, particularly in arthropods, used for biting and chewing food.

An immature form of an insect that resembles the adult in form and function. Nymph. In simple terms, a nymph is a young insect that looks similar to its adult form but is not fully developed.

The second pair of appendages in arachnids, used for sensing and for holding prey, is called a pedipalp. In simple terms, a pedipalp is a specialized limb in spiders and scorpions that helps them sense their environment and catch food.

The paired openings located in the pharynx, behind the mouth of a chordate embryo. Pharyngeal pouches are small pockets that develop in embryos and can become parts of the face, neck, or throat.

The third stage of complete metamorphosis, between larva and adult insect, is called pupa. A pupa is a life stage in which an insect transforms inside a protective casing before becoming an adult.

The silk-producing glands of a spider. Spinneret. A spinneret is a special organ in spiders that they use to produce and release silk threads.

A small hole in an insects thorax or abdomen for air to enter and leave. Spiracle. A spiracle is an opening on an insect's body that helps it breathe.

An arthropods midsection, behind its head, it may have legs and wings attached. Thorax. The thorax is the middle part of an insect's body where the legs and wings are connected.

One of the hollow tubes that transport air through the body in terrestrial arthropods. Tracheal tubes are small airways in insects that help them breathe by delivering oxygen directly to their tissues.