BIO 240 Study Guide - Final Guide: Terrestrial Animal, Circulatory System, Flatworm
Document Summary
Zoology test 2: protozoa (unicellular eukaryotes) are notable for their ability to move independently. Protozoa are heterotrophic microorganisms, and most species obtain large food particles by phagocytosis. Porifera (sponges)- these are multicellular organisms which are sessile/sedentary in nature. Most of them are marine while a few are fresh water forms. Body is cylindrical, asymmetrical or has radial symmetry. Body also contains one or more openings called oscula through which water passes out from the body. Sponges feed on minute organisms and small organic particles. Respiration takes place by diffusion of oxygen from water that is flowing into the body. Asexual reproduction takes place by external or internal budding (formation of gemmules) or by disintegration of body into reduction bodies. Cnidaria (sea anemones, corals, jellyfish)- most of them live in the ocean, but a few, like the hydra, live in freshwater. They have neither head nor brain, but a mouth, which is the single body opening.
