Test 2 Terms Flashcards
(29 cards)
Pseudocoelomate
body cavity called a pseudocoel. located between mesoderm and endoderm. Ex. Nematoda
Acoelomate
no body cavity. Ex.Flatworms
Coelomate
Fluid-filled body cavity which develops entirely within the mesoderm. Ex. Annelida
Schizocoel
true coelom arises through splitting of mesoderm
Enterocoel
true coelom arises as pouches of primitive gut
Protostome
the mouth develops first during gastrulation.
Blastopore is animals mouth; anus develops after at the other end
Deuterostome
the anus develops first during gastrulation.
Blastopore is the animal’s anus and the mouth develops after at the other end
Blind sac gut
Only one opening or ingestion and egestion; the mouth
Complete gut
has a mouth for ingestion and an anus for egestion
Morula
Solid ball of cells after cleavage
Blastula
Hollow ball of cells
Gastrula
blastula folded inward at one point to form a hollow sac with an opening at 1 end (blastopore). is an embryo
Cleavage
The process where a zygote undergoes a series of mitotic division
Bilateral Symmetry
Body design in which body has a right and left half that are mirror images of each other
Radial Symmetry
body design in which body parts are arranged around a central axis and any plane passing through central axis produces 2 mirror images halves
Diploblastic Body Wall
have 2 cellular layers, outer ectoderm and an inner endoderm.
Triploblastic Body Wall
have 3 cellular layers, ectoderm, mesoderm and endoderm
Determinate Cleavage
spiral cleavage (ball is smaller at the top and then expands further down)
Indeterminate Cleavage
Radial Cleavage (ball is completely spherical, equal all around)
Paratomy
Clonal reproduction where a chain of fully formed zooids separate by fission.
Architomy
Clonal reproduction by division into fragments. Each forms a cyst and the whole worm regenerates.
Homocellular Ovary
Yolk is an integral part of the egg
Heterocellular Ovary
Ovary ha 2 regions, germamium to produce egg
and vitellarium where yolk filled cells are produced and surrounds egg.
Open Circulatory System
Blood flows in open spaces called sinuses.