Biology 2- Animal Science 1.2

nine major phyla names

porifera, cnidaria, platyhelminths, nematodes, annelids, mollusca, arthropoda, echinoderms, chordates

non-bilateral animals

no bilateral symmetry, most ancient

complex life cycle

switches between asexual and sexual reproduction, polyps and medusas

phylum porifera

sponges - no organized tissues or structures, no symmetry, filter feeders, in through pores and out through osculum, three functional layers: choanocytes, mesophyll, outer epithelial layer, spicules for structure and defense

phylum cnidaria

jellyfish and anemones - diploblastic, specialized tissues in two levels, radial symmetry, incomplete digestive tract, complex life cycle

go back to non major phyla starting at 49 and classes

go back to non major phyla starting at 49 and classes

phylum platyhelminths

flatworms, flukes - parasitic, triploblastic, acoelomate, organ level organization, bilateral symmetry, incomplete digestive tract, lack specialized structure for gas exchange, complex life cycle

phylum nematoda

roundworms - pseudocoelom, organ level organization, no circulatory system, bilateral symmetry, unsegmented

phylum mollusca

snails, clams, octopuses - complex organs and mantle, coelom present but reduced, filter feeders with complete digestive tracts, open circulatory system with a few large vessels

phylum arthropoda

insects - most successful and 75% of species, chitin exoskeletons, segmented, coelom, organs, open circulatory system, respiratory system with trachea, complete digestive tract, joints, nervous and respiratory systems

phylum echinodermata

starfish - coelom, organs, endoskeletons, water vascular systems, bilaterally symmetrical larvae and radial adults, spiny skin marine, bilateral larval stage and radial adults, endoskeletons made of ossicles plates

phylum chordata

everything else, humans - four principle features are dorsal nerve chord, notochord, pharyngeal slits and postanal tail at some stage of life, organs, complete digestive system

internal and external fertilization

internal happens in animal body and external happens outside

cleavage patterns

protosome spirals, deuterostomes radial

what is the closest ancestor to animals 

protists

phylum annelida

segmented worms- most have bristles or setae, coelomates, organ level organization, complex and complete digestive tract, closed circulatory system, bilaterally symmetric

hemimetabolous vs holometabolous

three stage incomplete metamorphosis, egg, nymph, adult vs full metamorphosis with larval stage

traits of deuterostome animals

large and complex, pore development mouth second, 2 major phyla of echinodermata and chordata

diversity of ray fin fish

evolution of protrusible jaw that can be extended to bite

membranes of amniotic egg

chorion (gas exchange) amnion (encases embryo) yolk sac (surrounds yolk) allatois (surrounds waste cavity)

kinetic skull

lower jaw not directly attached to skull

hooves and horns

mammal trait, horns permanent and antlers temporary