TAMU Biology 112 Lab Practical 2 Exam Questions and Answers Verified 100% Correct

TAMU Biology 112 Lab Practical 2 Exam Questions and Answers Verified 100% Correct Phylum Brachiopoda - Lophophorates - ANSWER -Characterized by lophophore feeding structure Sessile True coelom Lophophore - ANSWER -Feeding structure which consists of a crown of ciliated tentacles surrounding the mouth Brachiopods vs. Bivalves (Molluscs) - ANSWER -Brachiopod: Lophophore PRESENT Pedicle PRESENT Symmetry PERPENDICULAR to valves Shell CALCITE; CALCIUM PHOSPHATE; PROTEINS Class Articula - ANSWER -Lamp shells Articulating valves hinged along the posterior edge Sockets or teeth which permit the valves to open along the anterior side for feeding Pedicle PERMANENTLY ATTACHED TO SUBSTRATE Lophophore SUPPORTED Gut BLIND Hinge COMPLEX, TOOTHED Shell INFLEXIBLE, CALCAREOUS Pedicle aperature PRESENT Outer layer CHITIN ABSENT Habitat ROCKS Class Inarticula - ANSWER -Primitive brachiopods Simple valve articulation Rely on musculature to open and close Lingula (oldest known animal genus) Pedicle TEMPORARILY ATTACHED Lophophore NOT SUPPORTED Gut COMPLETE Hinge SIMPLE, SMOOTH Shell FLEXIBLE, PROTEIN Pedicle aperature ABSENT Outer layer CHITIN PRESENT Habitat VERTICAL BURROWS IN SOFT SEDIMENT Phylum Mollusca - ANSWER -Bilateral symmetry Lack segments True coelom Basic body plan: -Muscular foot (locomotion) -Visceral mass (houses internal organs) -Mantle (protective tissue fold covers visceral mass) Snails, clams, and cephalopods Classes: -Polyplacophora -Gastropoda -Bivalvia -Cephalopoda Class Polyplacophora - ANSWER -Chitons Protective dorsal plates Class Gastropoda - ANSWER -Slugs and snails Torsion Radula Torsion - ANSWER -During embryonic development, asymmetrical muscle forms and contracts to rotate visceral mass 180 degrees resulting in anus and mantle cavity above adult head Radula - ANSWER -Specialized structure in marine gastropods used to scrape algae off rocks Class Bivalvia - ANSWER -Two valves that make up shell Hinged at mid-dorsal line, held together by adductor muscles Will open shell to extend muscular foot Gill filaments for feeding and gas exchange Open circulatory system Clams, scallops, oysters, muscles Class Cephalopoda - ANSWER -Complex sensory capability Well-developed nervous systems CLOSED circulatory system (only molluscs) Chambered Nautilus, squid, octopuses I.D. systemic heart, brachial heart, ink sac, siphon, pen, caecum Phylum Annelida - ANSWER -Free-living worms "Ring" segments extend to coelom as septa Complete digestive tract Primitive nervous system: dorsal ganglion (brain), ventral nerve cord Closed circulatory system with hemoglobin-based blood Trochophore larval stage Classes: -Errantia -Sedentaria Class Errantia - ANSWER -Mobile worms Class Sedentaria - ANSWER -Sessile worms I.D. mouth, clitellum, anus, pharynx, intestine, crop, gizzard Earthworm cross-section - ANSWER -Lumbricina Synapsid skulls vs. Diapsid skulls - ANSWER -Synapsids: they have single skull opening behind each eye Diapsids: two holes on each side of their skulls. Living diapsids include crocodiles, lizards, snakes and the tuatara Archenteron - ANSWER -Primitive gut Phylum Echinodermata - ANSWER -Sea stars and relatives Larvae bilaterally symmetrical Spiny protective skin Water vascular system -tube feet projections Skeleton of calcite plates