Exam 5 New Material Flashcards
Blastula
hollow mass of cells
Blastoderm
Actual layer of cells, enclosing the blastocoel
Blastocoel
Fluid filled central cavity
Gastrula
surface cells move inward to form this
cells begin to differentiate
The ten phyla are broken down under 4 categories
No tissue vs. true tissue (1)
Radial symmetry vs. bilateral symmetry (2)
body cavity type (3,4,5)
protostome vs deuterostome (6,7,8,9,10)
Parazoa vs Eumetazoa
Tissue: A group of cells functioning together with specialized functions Lack symmetry 1. Porifera (Sponges) Parazoa: lack tissue Eumetazoa: true tissue
Radial Symmetry
diploblast
have endoderm (lining of the digestive tract) and ectoderm (the outer covering)
2. Cnideria (jellyfish)
Bilateral Symmetry
triploblast
have endoderm, ectoderm and mesoderm (muscles and most organs)
cephalization (concentration of nerves)
Coelom
fluid lined body cavity that separates the gut from the outer body wall, protects organs
Acoelomates
Do not have a coelom
FLATWORMS
3. Platyhelminthes
Coelomates
have a coelom
ANNELIDS
Pseudocoelomates
Combination of both
NEMATODES
4. Rotifera (rotifers)
5. Nematoda (roundworms)
Protostomes
mouth developed first spiral determinate cleavage (fate is determined) 6. Mollusks 7. Annelids 8. Arthropods
Deuterostomes
anus developed first radial indeterminate (totipotent)- develop into anything 9. Echinoderms 10. Chordates
Protostome Coelomates
last 5 groups
Coelomate has the body cavity surrounded by tissue
Molluska
snails, octopuses, clams, sea slugs muscular foot (movement), visceral mass (housing organs) and mantle (tissue layer)
Annelida
earthworms, leeches
begin to see segmentation
earthworms aerate soil and add nutrients
Arthropoda
most successful insects, spiders, crustaceans exoskeleton made of chitin - limits molting true body segmentation jointed appendages
Echinoderms
deuterstome coelomates star fish, sea cucumbers, sea urchins radial symmetry as an adult bilateral symmetry at larval stage tube feet- suction cup appendages water vascular system