Unit 7 - Flatworms and Rotifers

Bilateral symmetry, Cephalization, Triploblastic, has coeolom.

Lophotrochozoa and Ecdysozoa

Tufts and rows of cilia

Ring of hollow, ciliated tentacles, Mouth is inside the ring, Anus is outside the ring.

Flatworms, No coelom, No skeleton, True muscle, circular, logitudinal and vertical.

Ventral epithelium is ciliated, Dual glands produce adhesive and nonadhesive mucus Rhabdite cells that provide physical protection.

Organisms that do not display parasitic traits

Non-ciliated syncytial tegument in parasitic forms, microvili

Incomplete or none at all, only a mouth and no anus.

A series of tubes that lead externally of the organism.

Mainly for osmoregulation - maintaining water balance with external environment. The Protonephridia is made of flame cells and tube cells.

Turbellaria, Trematoda, Monogea, Cestoda.

Tricladida and Polycladida, Dugesia and marine lifeforms.

All are endoparasites, have one or more oral suckers, hermaphroditic and gonochoristic.

Subclass Digenea have at least 2 host, Intermediate host is a mollusk, definitive host is a vertebrae.

Typically ectoparasites, Eggs hatch into larvae that attach to host, Opisthaptor for attachment.

All endoparasites, live in GI tract of host, no digestive system, instead absorb nutrients across their own wall.

Attaches to gut wall via a scolex, the tegument has many microtriches.

Each segment of a tapeworms body.

Tapeworms sexually reproduce in the hosts stomach and shed mature proglottids which are full of eggs.

Because their ciliated corona looks like rotating wheels.

Complete alimentary canal, pharynx contains mastax, salivary and gastric glands add digestive enzymes, digestive tube empties into cloaca, waste exits cloaca via anus which is dorsal.

2 protonephridia, collecting tubules carry excretory fluid to bladder, bladder empties into the cloaca, function both in excretion of nitrogenous waste and osmoregulation.

No heart or blood vessels, nutrients distributed via hemolymph throughout the hemocoel.

Bilobed brain lies dorsal to pharynx, A pair of ventral nerve cords contain nerve fibers connected to various sensory and motor organs.

Gonochoristic, Parthenogenesis is common, Class Bdelloidea has no males.