Animal Kingdom

Kingdom Animalia

• eukaryotic • heterotrophic by ingestion • multicellular • composed of cells not surrounded by a cell wall

and rely on structural proteins • (e.g. collagen) for support • composed of specialized tissues (except one

group) which arise from embryonic germ layers • typically motile; not sessile like plants • diploid and reproduce sexually

Traditional taxonomy has focused on body plans (called grades).

• Understanding these body plans will require you to understand some of the anatomical terms found on p. 67

• Dorsal - near or towards the back • Ventral - near or towards the belly • Superficial - near the surface • Deep - below the surface; under • Lateral - near or towards the sides; right & left • Median - near or towards the middle • Pectoral - relates to the chest • Pelvic - relates to the hips region • Anterior - near or towards the front end • Posterior - near or towards the hind end • Caudal - refers to the tail • Cranial - refers to the head • Longitudinal - parallel to the long axis from head to tail • Transverse - perpendicular to long axis from head to tail • Proximal - directional term; close to main part of body • Distal - directional term; far from the main part of the body

Animals will be classified based upon their :

• Symmetry • Tissue development • Body cavity development

Symmetry

• Asymmetrical • Radial symmetry • Bilateral symmetry

Tissues • Sponges are the

only group of animals without true tissues (parazoan)

• Eumetazoan animals have bodies which develop from distinct tissue layers –germ layers

• These germ layers are produced during the process of gastrulation in embryonic development.

• Endoderm • Ectoderm • Mesoderm

Diploblastic animal

Triploblastic animal

• Body cavities – triploblastic animals – Acoelomate – Pseudocoelomate – Coelomate

Phylum Porifera

• Sponges • No tissues

– Epidermal cells – Porocytes – amoebocytes – Choanocytes

• Spicules • Spongin

• Types of sponges – Bath and finger sponges – Glass sponges – Calcareous sponges, Grantia

Phylum Cnidaria

• Diploblastic – Ectoderm epidermis – Endoderm gastrodermis – Mesoglea

• Digestive system – incomplete: mouth only

• Gastrovascular cavity – Functions

• Tentacles – – Cnidocytes w/ nematocysts

• Growth forms – Polyp – Medusa

• Radial symmetry • Reproduction

– Asexual with budding – Sexual – motile sperm

Cnidocyte with nematocyst

Polyp vs. medusa growth forms

Hydra

Obelia

• Life cycle with asexual and sexual stages

• Polyp colony – asexual

• Medusae free-swimming sexual

Other Cnidaria examples

• Corals • Portuguese Man-o-War • Jellies

Phylum Platyhelminthes

• Triploblastic – Endoderm – Ectoderm – Mesoderm – muscle !

• Acoelomate – No body cavity

• Incomplete digestive system • Protonephridia • Dorso-ventrally flattened

. Label the life cycle of the pork tapeworm: final host, intermediate host, bladder worm larva, cyst in pork, ingestion of infected pork, ingestion of grass containing larvae, gravid proglottid, passing of proglottids through intestine