Radience

Invertebrates, Mollusks, Arthropods and Echinoderms

Science

antenna

a feeler on the head of a crustacean or insect
antenna Simple Definition

anus

the opening at the end of the digestive tract where waste leaves the body
anus Simple Definition

arthropod

an invertebrate with an exoskeleton, jointed legs, and segmented body, like any insect, spider, crab etc
arthropod Simple Definition

bilateral symmetry

body plan composed of two halves which are mirror images of each other
bilateral symmetry Simple Definition

closed circulatory system

a circulation system in which blood flows within a network of vessels
closed circulatory system Simple Definition

cnidarian

aquatic invertebrates with stinging cells, like a jellyfish
cnidarian Simple Definition

echinoderm

a marine invertebrate with an internal skeleton and a water vascular system, like a starfish
echinoderm Simple Definition

endoskeleton

an internal skeleton, it is made of bone and/or cartilage
endoskeleton Simple Definition

exoskeleton

the hard outer covering that protects some animals, like spiders
exoskeleton Simple Definition

insect

an arthropod with three body segments, six legs, two antennae, and compound eyes
insect Simple Definition

invertebrate

an animal without a backbone
invertebrate Simple Definition

larva

the immature form of an animal, it looks very different from the adult form
larva Simple Definition

lung

the respiratory organ that absorbs oxygen from the air and removes carbon dioxide from the blood
lung Simple Definition

medusa

an umbrella-shaped free-swimming organism, like a jellyfish or hydra
medusa Simple Definition

metamorphosis

changes in form as an animal becomes an adult
metamorphosis Simple Definition

mollusk

an animal with a soft body and a muscular foot, it may also have a shell, like a snail or squid
mollusk Simple Definition

molting

the shedding and replacement of an exoskeleton, skin or feathers
molting Simple Definition

open circulatory system

a system in which blood moves through open spaces as well as vessels
open circulatory system Simple Definition

polyp

a tube-shaped organism usually attached to a surface, it is a life stage of a cnidarian
polyp Simple Definition

radial symmetry

body parts arranged in a circle around a central point
radial symmetry Simple Definition

radula

a tonguelike organ with teeth in mollusks like snails
radula Simple Definition

tube feet

hollow tubes that end in suction cups, echinoderms use them to move and collect food
tube feet Simple Definition

water vascular system

a system of fluid-filled tubes in echinoderms like starfish
water vascular system Simple Definition

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