∑ - All organisms are classified into three domains. The Archaea and Bacteria domains are prokaryotes. These are organisms that do not have a membrane bound nucleus and their DNA is not associated with proteins. The Bacteria domain consists of Eubacteria and archaebacteria The Eukarya domain includes eukaryotes, or organisms that have a membrane bound nucleus. This domain is further subdivided into the kingdoms Protista, Fungi, Plantae, and Animalia Groups organisms primarily based on differences in ribosomal RNA structure. Ribosomal RNA is a molecular building block for ribosomes. ∑ - The principal taxa for classifying eukaryotes are kingdom, phylum, class, order, family, genus and species. ∑ - In a natural classification, the genus and accompanying higher taxa consist of all the species that have evolved from one common ancestral species. For natural classification, it is assumed that all members of that group shared a common ancestor at some point in their history. This can be seen in their structure. Unnatural or artificial classification for example would be birds and flies. They both can fly; however flight evolved separately, and they are classified separately β - Application: Classification of one plant and one animal species from domain to species level. Research one plant and one animal example and fill out the table below. Taxa Human Gray Wolf Kingdom Animalia Animalia Phylum Chordata Chordata
stems and leaves Filicinophyta Ferns and horsetails/large flat leaves/have stems and roots Seedless vascular plant/produce spores Coniferophyta Conifers/leaves are needles or scale-like leaves/woody stems Vascular plants/produce seed cones and seed scales Angiospermophyta Flowering plants, flowers and fruits with seeds have roots/stems and leaves Vascular plants/develop ovaries (eggs) and anthers (pollen) β - Application: Recognition features of porifera, cnidaria, platylhelmintha, annelida, mollusca, arthropoda and chordata. Animal Phyla Porifera Sponges/no mouth or anus Pores on the surface that suck in water for filter feeding/ no symmetry Cnidaria Corals, Sea anemones, hydra and jellyfish/ One opening for food and waste Generally soft accept species of hard corals/ radial symmetry/ Tentacles arranged around the mouth (some with stinging cells) Platyhelminthes Flatworms/ one opening for food and waste/lack body cavity except a gut/no circulatory or respiratory system Soft/no skeleton/flat thin ribbon-like shape/ bilateral symmetry Annelida Segmented worms such as earthworms and leeches/ segmented internal cavity with the same organs in each segment/mouth and anus Ringed shaped segments with bristles/ bilateral symmetry Mollusca Snails, bivalves and squid/most have calcium carbonate Mantle secretes shell/bilateral symmetry/most have radula (hard rasping tongue-like
(CaCO3) shell structure) for feeding Arthropoda Insects and crustaceans/mouth and anus/have head, thorax and abdomen Hard exoskeleton made of chitin/bilateral symmetry/ segmented bodies with jointed appendages Chordata All the vertebrates and a few (such as the tunicates - sea squirts) groups, have a mouth and an anus and have a dorsal strengthening structure called a notochord for at least some stage of their lives. Have a nerve cord lying above the notochord and have a series of pharyngeal slits that open up between the mouth and esophagus **Please note that Chordata has a sub-phylum called vertebrata (have a vertebral column) ** β - Application: Recognition of features of birds, mammals, amphibians, reptiles and fish. Birds (aves) Mammals (Mammalia) Amphibians (Amphibia) Reptiles (Reptilia) Fish (Osteichthyes) Skin covered in feathers made out of Keratin Skin has follicles with hair made out of Keratin Moist skin, permeable to water Impermeable skin covered in scales of keratin Scales made out of bony plates in the skin Lungs ventilated using air sacs, with tubes Lungs with alveoli, ventilated with ribs and a diaphragm Simple lungs and moist skin for gas exchange Lungs with extensive folding (increase SA) Gills covered by an operculum Pentadactyl Limbs No limbs Two wings and two legs Four legs for many, some have two arms/wings and two legs Adults have four legs Four legs in most species (some have none) Fins