Lophotrochozoa Bio Lab

Anterior

near the front of the body, or head

Aortic arches

a series of structures connected to the blood vessels that pump blood into the dorsal and ventral blood vessels

Beak (mollusks)

the basal projection of the oldest part of the shell of bivalve mollusks; a two-part structure situated in the buccal bulb within the head that functions as the jaws of the animal; the mandibles

Bivalve

have a shell divided into two halves and have a powerful adductor muscles that draw the two halves tightly together to protect the animal. Most are suspension feeders

Branchial Heart

a type of heart found in coleoid cephalopods that supplements the systemic heart

Cephalopod

are active marine predators; the muscular foot of a cephalopod has become modified into a muscular ex-current siphon and part of the tentacles

Cephalizaiton

possession of a head region that contains sense organs

Chromatophores

pigment-containing cells

Choanocytes

a flagellated feeding cell found in sponges. Also known as a collar cell

Circulatory system

a network of organs and vessels that function to flow blood, nutrients, hormones, oxygen and other gases to and from cells

Cirri

a hair-like filament found in many animals; the appendages of barnacles; the barbel of some fish ; feelers on both the anterior and posture ends of clam worms

Clitellum

the sexual reproductice organ of the earthworm

Corona

the ciliated mouth of a rotifer that propels the animal through the water and moves food particles to the mastax

Crop

the organ used for the storage of food in earthworms

Deuterostome

an animal with developmental mode characterized by the development of the anus from the blastopore; also disntingued by radial cleavage and by the body cavity forming as out-pockets of mesodermal tissue

Diploblastic

having two germ layers

Eumetazoan

a member of a clade of animals with true tissue. All animals except sponges and a few other groups

Esophagus

muscular tube connecting the mouth with the stomach

Fin

an external appendage used in propelling or guiding the body of many aquatic animals

Ganglion

a cluster of nerve cell bodies

Gastropod

most gastropods are marine. Undergo torsion. As gastropod embryo develops, its visceral mass rotates up to 180 degrees causing the animal’s anus and mantle cavity to end up above its head.

Gill (animal)

a respiratory organ found in many aquatic animals that extract dissolved oxygen from the water

Gizzard

the organ found in earthworms, used for mechanical digestion

Gonad

male or female gamete-producing organ

Hermaphroditic

a condition in which an individual functions as both male and female in sexual reproduction by producing both sperm and eggs

Inc sac

structure found in many cephalopods that produces ink

Incomplete gastrovascular cavity

only on opening in the gastrovascular cavity

intestine

a long tube running from the stomach to the anus and functions to absorb nutrients and water

Lophophore

crown of ciliated tentacles that surround the mouth and function in feeding

Mantle

a fold of tissue that drapes over the mollusks and may secrete a shell; one of three main parts of mollusks

Mastax

a muscular pharynx that contains the jaws of a rotifer

Medusa

the floating flattened mouth-down version of the cnidarian body plan

Metanephridia

an excretory organ found in many invertebrates that typically consists of tubes connecting the ciliated internal opening to external openings

muscular foot

a muscular structure usually used fir movement; one of three main parts of mollusks

nidamental gland

female reproductive organ found in the mantle of some mollusks that secretes the shell

Parapodia

in polychaete worms, a paired muscular appendage that functions in locomotion, sensation or respiration; an extension in sea slugs and other mollusks

Pen

a hard internal body part found in many cephalopods made of chitin like material and functions as a support for the organism and an attachment point for muscles

Pharynx

an area in the vertebrate throat where air and food passage cross; in flatworms, the muscular tube that protrudes from the ventral side of the worm and ends in the mouth

Polyp

the alternate form of the medusa

Polyplacophoran

chitons have a shell composed of 8 dorsal plates, but the chiton’s body itself is unsegmented

Posterior

near the back of the body or the rear end

proglottids

the body regions of the tapeworm, sometimes containing ovaries, testis, or egg

Protosomes

an animal with the developmental mode distinguished by the development of the mouth from the blastophore; often characterized by spiral cleavage by the body cavity forming when solid masses of mesoderm split.

Scolex

the head region od a parasite tapeworm

Seminal receptacle

a female reproductive structure that functions as the storage organ for male gametes

Septa

a wall that divides a cavity or structure into smaller ones; in coral, one of the radial calcareous plates

Setae

a stiff structure that resembles a har or bristle; in earthworms, hair-like strucutre that create traction against a substrate and aid in locomotion

Siphon

an external valve found in most mollusks used for waste excretion, get propulsion, and transfer of sperm and egg

Tentacle

an appendage used for grasping or moving around

Trochophore

a distinctive larval stage observed in some lophotrochozoan anima, including annelids, and mollusks

Visceral Mass

in mollusks, it contains most of the internal organs; one of the three main parts of a mollusk