Classification The three-domains Bacteria Archaea Eukarya The six-kingdom system Bacteria Archaea Protista Plantae Fungi Animalia The traditional five-kingdom system Monera Protista Plantae Fungi Animalia
(Forams and Radiolarians) Rhizarians Rhodophyta Alveolates Stramenopile CHLOROPHYTA AMOEBOZOANS Euglenozoa
Evidence indicates that animals evolved from choanoflagellates (protists) ~ 570 mya Single cells Often clonal Heterotroph No specialization or coodination between cells
Animal Classification 1. DNA sequencing 2. Body Symmetry 3. Presence or absence of body cavity 4. Embyonic Development
Symmetry
Body Cavity Most bilateral animals have body cavities Body cavities are fluid-filled cavities between the digestive tube and the outer body wall Functions: skeleton, providing support for the body and a framework against which muscles can act protective buffer between the internal organs and the outside world They can allow organs to move independently of the body wall
Body Cavity? epidermis gut cavity A No coelom (acoelomate animal) organs packed between gut and body wall Fig. 25-4a, p. 405
Body Cavity? epidermis gut cavity B Pseudocoel (pseudocoelomate animal) unlined body cavity around gut Fig. 25-4b, p. 405
Body Cavity? epidermis gut cavity C Coelom (coelomate animal) body cavity with a lining (dark blue) derived from mesoderm Fig. 25-4c, p. 405
Protostomes Embryonic Development Blastopore forms mouth first Deuterostomes Blastopore forms anus first
Porifora - sponges Sessile (Larva motile) No true tissues or organs Exhibit asymmetry or radial symmetry Filter feeders
Sponge Anatomy (water flow out of the sponge) epithelial cell pore spicules (water flow into the sponge) amoeboid cell pore cell collar cell (water flow) Fig. 23-5
Sponge filtration/feeding Collar Cell Collar Cell http://www.youtube.com/ watch?v=t7e1rq7zhlc&feat ure=player_embedded http://www.youtube.com/watch?v =29W77870BgE&list=PLVN5247pO BYcE1Mn_pWHIL9l0sMIx19TI
Figure 23-4 The diversity of sponges Copyright 2011 Pearson Education, Inc.
Cnidaria Sea Anemone Radial symmetry Two tissue layers Filled with water supports body Nerve net Nematocysts -stinging organelles that release toxins
Cnidarian Weaponry: The Cnidocyte trigger filament trigger nuclei (b) Cnidocytes Fig. 23-8
Cnidaria: Symbiosis Coral is a mutualism between photosynthetic dinoflagellates (protist) and a cniderian (animal) Algae in coral called zooxanthelle
In many coral species polyps form colonies Cnideria video Colonial polyps secrete a hard external skeleton of calcium carbonate The skeleton remains after the polyp dies New polyps build on the skeletal remnants of earlier generations
Copyright 2011 Pearson Education, Inc. Figure 23-6a Anemone
Copyright 2011 Pearson Education, Inc. Figure 23-6b Sea jelly
Copyright 2011 Pearson Education, Inc. Figure 23-6c Coral
Figure 23-7a Polyp mouth lining of gastrovascular cavity body wall tentacle gastrovascular cavity (a) Polyp foot Copyright 2011 Pearson Education, Inc.
Medusa lining of gastrovascular cavity gastrovascular cavity body wall tentacle (b) Medusa mouth Copyright 2011 Pearson Education, Inc.
Nematoda - round worms Exoskeleton (molts) Unsegmented Psuedocoelom (false body cavity) Bilateral worms 3 tissue layers Parasites and decomposers
A freshwater nematode posterior end intestine anterior end ovary vagina eggs mouth cuticle Copyright 2011 Pearson Education, Inc.
Copyright 2011 Pearson Education, Inc.
Platyhelminthes - flatworms Bilateral symmetry 3 tissue layers Cephalization (nerve mass) True organs and organ systems Aceolomate (no body cavity) Parasitic forms but some free living
Figure 23-9 Flatworm diversity Copyright 2011 Pearson Education, Inc.
Figure 23-17 The exoskeleton allows precise movements Copyright 2011 Pearson Education, Inc.
Figure 23-18 The exoskeleton must be molted periodically Copyright 2011 Pearson Education, Inc.
antennae abdomen thorax head compound eye mouth parts wing Copyright 2011 Pearson Education, Inc.
Copyright 2011 Pearson Education, Inc.
Copyright 2011 Pearson Education, Inc. Figure 23-21a Aphid
Copyright 2011 Pearson Education, Inc. Figure 23-21b Ant
Copyright 2011 Pearson Education, Inc. Figure 23-21c Beetle flying
Copyright 2011 Pearson Education, Inc.
Copyright 2011 Pearson Education, Inc.
Copyright 2011 Pearson Education, Inc.
Copyright 2011 Pearson Education, Inc.
Copyright 2011 Pearson Education, Inc. The diversity of myriapods
Copyright 2011 Pearson Education, Inc. Figure 23-24c Hermit Crab
Copyright 2011 Pearson Education, Inc. Figure 23-24d Barnacles
Copyright 2011 Pearson Education, Inc. Figure 23-24b Sowbug
Annelida - segmented worms Polychaetes- many hairlike chetae 12,000 species Mostly marine Oligochaets- few or no chetae Earthworms 10,000 species Aquatic or terrestrial decomposers Hirudinia- leeches 700 species
coelom intestine nephridia excretory pore ventral nerve cord anus coelom brain mouth pharynx ventral vessel hearts esophagus crop gizzard intestine ventral nerve cord Copyright 2011 Pearson Education, Inc.
Copyright 2011 Pearson Education, Inc. Diverse annelids
Mollusca (clams, snails, slugs, octopuses & squids) unsegmented bilateral symmetry coelomates aquatic & terrestrial possess all organ systems
Figure 23-14 The diversity of gastropod mollusks Copyright 2011 Pearson Education, Inc.
The diversity of bivalve mollusks Copyright 2011 Pearson Education, Inc.
Copyright 2011 Pearson Education, Inc. Figure 23-16a Octopus
Copyright 2011 Pearson Education, Inc. Squid
Copyright 2011 Pearson Education, Inc. Figure 23-16c Nautilus
Copyright 2011 Pearson Education, Inc. Figure 23-27a Sea cucumber
Copyright 2011 Pearson Education, Inc. Figure 23-27b Sea urchin
Copyright 2011 Pearson Education, Inc. Figure 23-27c Sea star