Platyheminthes Flashcards
Acetabulum
Cup-shaped structure, especially a sucker
Acoelomate
Organisms that have lost their coelom, resulting in spongy and porous mesh through which fluids readily move acting as a circulatory system
Adhesive gland
Gland in which secreted fluids will help the flatworm stick to its host.
Auricle
Small bundles of nerves found on the heads of flatworms (giving them their strange shape), function as sensory organs to distinguish which side a stimulus is coming from
Bilateria
Organisms with bilateral symmetry and three germ layers
Blastopore
The opening of the archenteron in the gastrula that develops into the mouth in protostomes and the anus in deuterostomes
Blastula
An early form of an embryo undergoing developmental processes, such as (spiral or radial) cleavage. It is marked by the presence of blastocoel and cells made up of around 128 cells
Cercaria
a free-swimming larval stage in which a parasitic fluke passes from an intermediate host (typically a snail) to another intermediate host or to the final vertebrate host
Cerebral ganglion
one of a pair of ganglia situated in the head or anterior part of the body in many invertebrates in front of or dorsal to the esophagus; also : a median ganglion formed by the fusion of such a pair
Chemoreception
Sensory function for flatworms translating a chemical signal into an action potential
Circular muscle
Muscle layer encircling the body between the epidermis and longitudinal muscle layer
Coelom
A fluid-filled body cavity completely lined by tissue created from the mesoderm
Cysticercus
A larval tapeworm that is at a stage in which the scolex is inverted in a sac, and that is typically found encysted in the muscle tissue of the host
Definitive host
The host in which a parasite reproduces sexually
Deuterostomia
Group of animals containing true body cavities (coelom), blastopore anus, radial cleavage, mesodoerm and coelom form from outgrowths of the primitive gut
Diverticulum
An abnormal pouch or sac opening from a hollow organ
Dorsoventral muscle
Muscles going from back to front (belly and back) of the body
Dual gland adhesive organ
Viscid gland cells fasten microvilli of anchor cells to the substrate; secretions of releasing gland cells provide a quick chemical detachment
Ecdysozoa
Syperphylum with organisms that develop a three-layered cuticle which they later will shed and grow back
Ectoderm
The outermost layer of cells or tissue of an embryo in early development, or the parts derived from this, which include the epidermis and nerve tissue
Ectoparasite
A parasite, such as a flea, that lives on the outside of its host
Endoderm
(AKA gastroderm) inner cell lining used for digestion
Endoparasite
A parasite, such as a tapeworm, that lives inside its host
Enterocoel
A coelom or coelomic cavity, present in some invertebrates, which has developed from the wall of the archenteron
Euceolomate
Any of the animals with “true” coelom, which is characterized by a body cavity completely lined with a peritoneum that attaches to organ
Eye cup
In planaria, a primitive eye that detects light and its direction
Flame cell
one of the hollow cells terminating the branches of the excretory tubules of certain invertebrates, having a tuft of continuously moving cilia
Gastrulation (Gastrula)
The process in which a metazoan embryo in an early state of germ layer formation following the blastula stage, consisting of a cuplike body of two layers of cells, the ectoderm and endoderm, enclosing a central cavity, or archenteron, that opens to the outside by the blastopore: in most animals progressing to the formation of a third cell layer, the mesoderm.