EntoproctaEntoprocta Entou'prQkt@ (inside rectum/anus), or Kamptozoa kaem(p)t@'zou@, is a phylum of mostly sessile aquatic animals, ranging from long. Mature individuals are goblet-shaped, on relatively long stalks. They have a "crown" of solid tentacles whose cilia generate water currents that draw food particles towards the mouth, and both the mouth and anus lie inside the "crown". The superficially similar Bryozoa (Ectoprocta) have the anus outside a "crown" of hollow tentacles.
PolychaetePolychaeta (ˌpɒlɪˈkiːtə) is a paraphyletic class of generally marine annelid worms, commonly called bristle worms or polychaetes (ˈpɒlɪˌkiːts). Each body segment has a pair of fleshy protrusions called parapodia that bear many bristles, called chaetae, which are made of chitin. More than 10,000 species are described in this class. Common representatives include the lugworm (Arenicola marina) and the sandworm or clam worm Alitta.
AcoelaAcoela, or the acoels, is an order of small and simple invertebrates in the subphylum Acoelomorpha of phylum Xenacoelomorpha, a deep branching bilaterian group of animals, which resemble flatworms. Historically they were treated as an order of turbellarian flatworms. The etymology of "acoel" is from the Ancient Greek words ἀ (), the alpha privative, expressing negation or absence, and κοιλία (), meaning "cavity". This refers to the fact that acoels have a structure lacking a fluid-filled body cavity.
FlatwormThe flatworms, flat worms, Platyhelminthes, or platyhelminths (from the Greek πλατύ, platy, meaning "flat" and ἕλμινς (root: ἑλμινθ-), helminth-, meaning "worm") are a phylum of relatively simple bilaterian, unsegmented, soft-bodied invertebrates. Unlike other bilaterians, they are acoelomates (having no body cavity), and have no specialised circulatory and respiratory organs, which restricts them to having flattened shapes that allow oxygen and nutrients to pass through their bodies by diffusion.
NephridiumThe nephridium (plural nephridia) is an invertebrate organ, found in pairs and performing a function similar to the vertebrate kidneys (which originated from the chordate nephridia). Nephridia remove metabolic wastes from an animal's body. Nephridia come in two basic categories: metanephridia and protonephridia. All nephridia- and kidney- having animals belong to the clade Nephrozoa. A metanephridium (meta = "after") is a type of excretory gland found in many types of invertebrates such as annelids, arthropods and mollusca.
BryozoaBryozoa (also known as the Polyzoa, Ectoprocta or commonly as moss animals) are a phylum of simple, aquatic invertebrate animals, nearly all living in sedentary colonies. Typically about long, they have a special feeding structure called a lophophore, a "crown" of tentacles used for filter feeding. Most marine bryozoans live in tropical waters, but a few are found in oceanic trenches and polar waters. The bryozoans are classified as the marine bryozoans (Stenolaemata), freshwater bryozoans (Phylactolaemata), and mostly-marine bryozoans (Gymnolaemata), a few members of which prefer brackish water.
Segmentation (biology)Segmentation in biology is the division of some animal and plant body plans into a series of repetitive segments. This article focuses on the segmentation of animal body plans, specifically using the examples of the taxa Arthropoda, Chordata, and Annelida. These three groups form segments by using a "growth zone" to direct and define the segments. While all three have a generally segmented body plan and use a growth zone, they use different mechanisms for generating this patterning.
CestodaCestoda is a class of parasitic worms in the flatworm phylum (Platyhelminthes). Most of the species—and the best-known—are those in the subclass Eucestoda; they are ribbon-like worms as adults, known as tapeworms. Their bodies consist of many similar units known as proglottids—essentially packages of eggs which are regularly shed into the environment to infect other organisms. Species of the other subclass, Cestodaria, are mainly fish infecting parasites.
Fishing baitFishing bait is any substance used to attract and catch fish, e.g. on a fishing hook. Bait items are both selected from and placed within the environment in order to capture prey. Traditionally, fishing bait is natural fish food such as night-crawlers, insects, worms, and smaller bait fish. Fishermen also use lures such as processed food, plastic baits and bionic lures to attract fish. Despite the importance of fish's attraction to bait, the way fish react to different baits is quite poorly understood.
Evolutionary gradeA grade is a taxon united by a level of morphological or physiological complexity. The term was coined by British biologist Julian Huxley, to contrast with clade, a strictly phylogenetic unit. An evolutionary grade is a group of species united by morphological or physiological traits, that has given rise to another group that has major differences from the ancestral condition, and is thus not considered part of the ancestral group, while still having enough similarities that we can group them under the same clade.
