1
 Todays Objectives

• TSW be able to recognize and give examples of the
  three types of symmetry found in animals.
• TSW be able to properly use directional terms for
  anatomical position.
• TSW be able to draw the three types of
  triploblastic body plans.

2
Symmetry

• Asymmetry
• Radial Symmetry
• Bilateral Symmetry

3
Asymmetrical animals

• Sponges

4
Radially Symmetrical Animals

• Cnidarians
• Coelenterates
• Nematodes
• Annelids
• Ctenophorans
• Echinoderms

5
Bilaterally Symmetrical Animals

• Platyhelminths
• Chordates
• Fishes
• Herps
• Birds
• Rotifers
• Molluscs
• Arthropods
• ALLOWS FOR CEPHALIZATION!

6
Directional Orientation

• Anterior vs. Posterior
• Dorsal vs. Ventral
• Medial vs. Lateral
• Distal vs. Proximal
• Inferior vs. Superior
• Cephalic vs. Caudal
• Aboral vs. Oral

7
Body Plans

• Acoelomate
• Pseudocoelomate
• Eucoelomate

8
Tissue Layer Body Plans

• Diploblastic ectoderm and gastroderm separated
  by mesoglea
• Triploblastic - ectoderm, mesoderm and endoderm
• Acoelomate
• Pseudocoelomate
• Eucoelomate

9
Acoelomate Body Plans

• Solid mass of cells between endoderm and ectoderm
  (parenchyma)

10
Pseudocoelomate Body Plans

• Body cavity not entirely lined with mesoderm
• Pseudocoelom comes from blastocoel

11
Eucoelomate Body Plans

• Cavity completely lined with mesoderm (peritoneum
  and serosa)
• Visceral structures suspended

12
Review Items

• Draw each type of triploblastic body plan and
  label each germ layer.
• Name at least one phylum of animals that falls
  into each category of symmetry.

13
Anatomical Position Review

• Use the proper terms to describe the relationship
  between the following body parts
• A) hand is ____ to the elbow
• B) knee is ____ to the head
• C) bellybutton is ____ to the spinal cord
• D) heart is ____ to the lungs
• E) head is ____ to the neck (2 terms fit here)
• F) wrist is ____ to the fingers