BIOL 2003 Lecture Notes - Lecture 12: Circulatory System, Cryptobiosis, Panarthropoda
Document Summary
Two synapomorphies of panarthropoda, hemocoel cavity (during embryonic development, where mesoderm would form, part connects to side of blastocoel and becomes hemocoel, ventrolateral leg (doesn"t matter whether segmented or jointed) Phylum onychophora: velvet worms, 70 species, tropical and subtropical leafy habitats, unjointed legs. Soft cuticle (hydrophobic so it repels water and makes it look like velvet) Phylum tardigrada: water bears, marine, freshwater, damp terrestrial. Can find them anywhere: 900 species, 8 unjointed legs, cryptobiosis (abiotic state, create ton that can survive virtually anything, freezing temperatures) Sucking pharynx (eat plant juices or other small invertebrates: anyhydrobiosis: life without water. Become ton state, synthesis of special molecules that form molecules that fill where water was supposed to be. Inverts with segmented bodies, jointed limbs, and an exoskeleton made of chitin: over 80% of named animals (1. 5+ million species, marine, freshwater, terrestrial, and the air, human important.