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Deuterostomes Protostome Vs Deuterostome Protostome

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Deuterostomes Protostome Vs Deuterostome Protostome Protostome vs Deuterostome First-Mouth Second - Mouth Deuterostomes Lab 7 Protostome vs Deuterostome Cleavage Gastrula Gastrula •Protostome • Deuterostome (Diploblastic) (Triploblastic) • Determinate Cleavage • Indeterminate Cleavage Ectoderm – Embryonic cell has a – Embryonic cells can destiny become anything Endoderm – Take one cell = loss of all – Take one cell away others tissues that would come compensate Mesoderm from that cell – You grow a twin from the one cell you took away Archenteron- Space within endoderm Blastopore Blastopore Archenteron: becomes adult digestive tract Blastopore: becomes the mouth or anus 1 Coelom Formation Cleavage •Deuterostome – Enterocoelom •Deuterostome • From the Archenteron – Radial • Folds/pinches from Endoderm •Protostome •Protostome – Schizocoelom –Spiral • Schizo = split • Spit from Endoderm Phylum Echinodermata (echino- spines or spiky, dermata- skin) • Pentaradical- 5 planes Today’s Phyla • Ossicles- CaCO3 endoskeleton • Large Coelom Echinodermata • Water vascular system Chordata • Tube feet •Spines 2 Phylum Echinodermata Class Asteroidea • Know the differences • Central Disk between the classes •5 Rays – Ossicle configuration • Pedicellariae – Type of pedicellariae, spines or spikes • Tube feet on base – Placement of mouth • Eye Spot – Size of tube feet •Predator – How does each exhibit – Feeds on Bivalvia pentaradial symmetry Class Ophiuroidea Class Echinoidea • Similar to Asteroidea • Long Spines (urchin) •Browsers • Smaller, thinner rays – Feed on algae, polyps, and detritus • Long tube feet • Coelom only in central disk • Test: fused ossicles • Pentaradial symmetry obscured • Faster, more flexible 3 Class Holothuroidea Class Crinoidea • Oblong, lateral plane of • Sea Lilies & Feather symmetry Stars • Tentacles at mouth • Sessile (don’t move) • Tube feet pentaradial place lengthwise • Central stalk with rays • Crawl or burrow • Filter feeder – Tube feet on branches • Feeds on detritus move catch food Phylum Chordata Common Traits Chordata 1. Notochord • Know the differences between the classes 2. Pharyngeal gill slits – When does it have a notochord? – When does it have gill slits? 3. Dorsal, tubular nerve – What do the gill slits turn into? (Vertabrata) chord – What kind of skeleton does it have? 4. Post anal tail – What kind of epidermis does it have? – What special epidermal structures does it have? – Exothermic or Endothermic? – Does the egg develop in the water or in an amniotic sac? 4 Subphylum Urochordata Subphylum Cephalochordata • All Marine • All Marine • Larvae – Pharyngeal gill slits • Fish-like – Post anal tail – Notochord – Dorsal, tubular nerve • Adults chord – Pharyngeal gill slits • Adults – Post anal tail – Pharyngeal gill slits – Notochord – Post anal tail – Dorsal, tubular nerve chord Subphylum Vertabrata Superclass Agnatha • Skull & vertebrae • No paired appendage column •No jaw • Components differ • Cartilage skeleton by class • All stages – Pharyngeal gill slits – Post anal tail – Notochord – Dorsal, tubular nerve chord 5 Superclass Gnathostomata Superclass Gnathostomata • Paired appendages • Know differences •Jaws between classes • Cartilage or bone – Chondrichthyes skeleton – Osteichthyes –Amphibia – Reptilia –Aves –Mammalia 6.
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