Survey
* Your assessment is very important for improving the work of artificial intelligence, which forms the content of this project
Download (a) Cleavage
Document related concepts
no text concepts found
Transcript
Fig. 32-1 Fig. 32-2-3 Blastocoel Cleavage Endoderm Cleavage Blastula Ectoderm Zygote Eight-cell stage Gastrulation Blastocoel Cross section of blastula Gastrula Blastopore Archenteron Fig. 32-3 Individual choanoflagellate Choanoflagellates OTHER EUKARYOTES Sponges Animals Collar cell (choanocyte) Other animals Fig. 32-7 (a) Radial symmetry (b) Bilateral symmetry Fig. 32-8 Coelom Digestive tract (from endoderm) Body covering (from ectoderm) Tissue layer lining coelom and suspending internal organs (from mesoderm) (a) Coelomate Body covering (from ectoderm) Pseudocoelom Muscle layer (from mesoderm) Digestive tract (from endoderm) (b) Pseudocoelomate Body covering (from ectoderm) Tissuefilled region (from mesoderm) Wall of digestive cavity (from endoderm) (c) Acoelomate Fig. 32-9 Protostome development (examples: molluscs, annelids) Deuterostome development (examples: echinoderm, chordates) Eight-cell stage Eight-cell stage Spiral and determinate (a) Cleavage Radial and indeterminate (b) Coelom formation Key Coelom Ectoderm Mesoderm Endoderm Archenteron Coelom Mesoderm Blastopore Blastopore Solid masses of mesoderm split and form coelom. Mesoderm Folds of archenteron form coelom. Anus Mouth (c) Fate of the blastopore Digestive tube Mouth Mouth develops from blastopore. Anus Anus develops from blastopore. Fig. 32-10 “Porifera” Eumetazoa Metazoa ANCESTRAL COLONIAL FLAGELLATE Cnidaria Ctenophora Deuterostomia Ectoprocta Brachiopoda Echinodermata Bilateria Chordata Platyhelminthes Protostomia Rotifera Mollusca Annelida Arthropoda Nematoda Metazoa Silicea Calcarea Ctenophora Eumetazoa ANCESTRAL COLONIAL FLAGELLATE “Porifera” Fig. 32-11 Cnidaria Acoela Bilateria Deuterostomia Echinodermata Chordata Platyhelminthes Lophotrochozoa Rotifera Ectoprocta Brachiopoda Mollusca Annelida Ecdysozoa Nematoda Arthropoda Fig. 32-UN1 Common ancestor of all animals Metazoa Sponges (basal animals) Eumetazoa Ctenophora Cnidaria Acoela (basal bilaterians) Deuterostomia Bilateral summetry Three germ layers Lophotrochozoa Ecdysozoa Bilateria (most animals) True tissues
Related documents