Invertebrated Animals


Chapter Objectives

At the end of this unit students will be able to
1. identify common features of animals
2. distinguish radial symmetry from bilateral symmetry.
3. identify the primary germ layers and the tissues arising from each.
4. identify the different types of body cavities and their advantages and limitations.
5. describe the advantages of body segmentation.
6. list the milestones in the evolutionary development of animals.
7. summarize the functions of the body systems of animals.
8. differentiate between open and closed respiratory systems.
9. differentiate asexual and sexual reproductive strategies.
10. describe the characteristics and provide examples for the major phyla of invertebrates.

Chapter Terms

Introduction to Animals Invertebrates
blastula
endoderm
ectoderm
mesoderm
body plan
asymmetrical
radial symmetry
bilateral symmetry
cephalization
coelom
acoelomate
pseudocoelomate
coelomate
phylogenetic tree
gastrovascular cavity
respiration
gill
open circulatory system
closed circulatory system
hydrostatic skeleton
exoskeleton
endoskeleton
hermaphrodite
external fertilization
internal fertilization

Cnidarian
Platyhelminthes (flatworms)
Nematoda (round worms)
Mollusca
Annelida
Arthropoda
Echinodermata
Chordata
sessile
medusa
polyp
fluke
segmentation
trachea
spiracle
thorax
abdomen
compound eye
metamorphosis
notochord
protostome
deuterostome
pharyngeal gill slit

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