Animals
• Multicellular• Heterotrophic-• Aerobic- require oxygen• Most produce sexually most of the time• Most are mobile most of the time• Embryonic Development
– Ectoderm: Outer Layer– Endoderm: Inner Layer– Mesoderm: Middle Layer
dorsal
posterior
ventral
anterior
Radial symmetry
Bilateral symmetry
No Coelom vs. Coelom
epidermis gut cavity
no body cavity; region between gut and body wall packed with organs
Acoelomate organism(flatworm)
No Coelom
epidermis gut cavity
unlined body cavity (pseudocoel) around gut
Pseudocoelomate organism(roundworm)
Psuedocoel
epidermis gut cavity
peritoneum
lined body cavity (coelom); lining also holds internal organs in place
Coelomate organism
Coelom
Sponge
Sea anemone Coral
Figure 16.7(1)Page 267
Do not post to Internet
outer epithelium (epidermis)
mesoglea(matrix)
inner epithelium (gastrodermis)Medusa
Polyp
Cnidarian body plans
pharynx (protruded)
genital poreoviducttestisovary
branching gut
branching units collect and expel excess water
Do not post to Internet
Flukes mature and mate in human host
Fertilized eggs exit in feces
Ciliated larva hatches
Larva burrow into snail; multiply asexually
Fork-tailed larva leave snail, enter human host
Tape Worms
Portion of a tapeworm
Do not post to Internet
proglottids scolex
Worm Body Structure
Figure 16.18bPage 273
Do not post to Internet
Polychaete Worm
Arthropods
Lobster
ArtrhopodCrustaceans
egg
Larva molts five times
Female carries fertilized eggs under abdomen until they hatch
Young crab molts many times before reaching maturity, and throughout lifetime thereafter
Do not post to Internet
Mollusk
Mollusk Body Plan
Mollusks
Another Mollusk
Echinoderms
Sea Star
Sea urchins
Sea cucumber
Brittle starDo not post to Internet
Vertebrates
dorsal, tubular nerve cord
notochord
pharynx with gill slits tail extending past anus
anus
pore of atrial cavityhindgut
gonadaorta
midgut
segmented muscles
tentaclelike structures
around mouth
Lancelet
Early jawless fish (an agnathan)
supporting structures
gill slit
jaw Early jawed fish (a placoderm)
Galápagos shark
Manta rayDo not post to Internet
caudal fin dorsal fin dorsal fin
pelvic fin(pair)
pectoral fin(pair)
anal fin
inside lobed fin; bony or cartilaginous structures (orange) undergoing modification
limb bones of an early amphibian
Do not post to Internet
yolk sac embryo
chorion
amnion
albumin (“white” of the egg)hardened shell
allantois
Figure 16.32bPage 283
Do not post to Internet
Birds
Confuciusornis sanctusDo not post to Internet
Mammals
Koala
Fig. 16.33d,ePage 284
Bat
Do not post to Internet
Figure 16.33fPage 284
Do not post to Internet