BIO 3102 Study Guide - Silurian, Hemolymph, Placodermi
Document Summary
Includes jawless fish such as lampreys and hagfish: cartilage based skeletons, use of gills, earliest vertebrates, muscular pharynx to suck in water containing food particles. Alternation of generations: represents life cycle of plants, varies between diploid sporophyte and haploid gametophyte. Antheridia: a rounded gametangia (mechanism by which plant holds gamete, flagellated sperm form in this, present in bryophyte gametophytes, exists in contrast to the archegonium which houses and protects the egg cell. Archegonia: flask shaped gametangia, egg cell forms in this, houses and protects egg cell, present in bryophyte gametophytes. Includes crustaceans, arachnids: segmented body encased in exoskeleton, coelom is greatly reduced, has a haemocoel filled with blood like haemolymph, marine arthropods have gills for diffusion, compound eyes. Bony fish: developed before cartilagenous fish, have hard endoskeleton composed of bones, rely on diffusion of oxygen in water across gills, closed circulatory systems.
