describing biodiversity - classification Flashcards
yr 11 unit 1
classification systems
provide methods of sorting, so similar or related organism are grouped together. classification is hierarchical. classification is important to identify & organise information about organisms, assist in identification of invasive species, describing biodiversity in ecosystems, and creates universal scientific communication between scientists
hierarchy of classification
domain => kingdom => phylum => class => order => family => genus => species
binomial name
scientific name, first with a genus second with a species. e.g. “Homo sapiens” underlined/italicised
eukarya
eukaryotes - contains DNA, nucleus & membrane bound
prokaryotes
archaea & bacteria, no nucleus or membrane bound organisms
structural characteristics
how similar species are based off physical characteristics (morphology)
methods of reproduction
considered variable (e.g. asexually sexually)
molecular sequences
can reveal subspecies of animals, used to distinguish and classify
porifera
-asymmetrical (no definite symmetry)
-multicellular body, few tissues & no organs
-cells & tissues surround a water-filled space but there is no true body cavity
-all are sessile (as an adult, live attached to something)
-reproduce asexually or sexually
cnidaria
-radically symmetrical (body plan is circular with structures that radiate out)
-gastrovascular cavity with single opening that serves as both mouth and anus
-reproduce sexually & asexually
-simple, net-like nervous system
-live in aquatic environments, mostly marine
mollusca
-bilaterally symmetrical
-body without cavity
-body has thorough gut (with mouth and anus)
-uses muscular foot for locomotion
-open circulatory system with heart and aorta
platyhelminthes
-bilaterally symmetrical (left & right halves of body are mirror images)
-gastrovascular cavity with single opening that serves both as mouth and anus
-body has three layers of tissues, with organs
-body without cavity
-body has blind gut (mouth but no anus)
-flattened body shape
amelida
-bilaterally symmetrical
-body has more than two cell layers, tissues & organs
-body cavity, nervous system & closed circulatory system
-body has thorough gut (with mouth & anus)
nemaroda
-bilaterally symmetrical
-cylindrical morphology
-body covered by tough cuticle (of collagen and chitin)
-alimentary canal (digestive system) with mouth & anus, but no circulatory system
-found in most aquatic habitats, soil, moist tissues of plants, and body fluids & tissues of animals
arthropods
-usually bilaterally symmetrical
-segmented
-hard exoskeleton (external, skeletal of protein and chitin)
-must have through gut (with mouth & anus)
-jointed appendages (body parts attached to main trunk such as arms, legs, wings); has 3-400 pairs of jointed legs
echinodermata
-five rayed symmetry, mostly radial, sometimes bilateral
-body has more than two cell layers, tissues & organs
-thin epidermis covering and endoskeleton; most species prickly due to skeletal bumps & spines
-most have short, through gut with mouth and anus
-body shape highly variable, but with no head
chordate
-90% are vertebrates (have backbones) with two invertebrate groups
-have the following features during development, possibly as embryo), pharyngeal slits, dorsal nerve, notochord, post anal tail
vertebrates - five main classes
-fish: scales made of bony pilates, gills
-amphibian: moist skin, skin permeable to gases, gills during larval stages, lungs as adults
-reptilia: scales made of keratin, lungs with excessive folding
-birds: feathers made of keratin, lungs with bronchian tubes
mammals: skin with follicles which produce hair or fur made out of keratin, lungs with alveoli
mammel subclasses
-monotreme (lays eggs)
-marsupials (nurtured within pouch as a fetus)
-placental (embryonic fetal organ)
bryophytes
non-vascular land plants (mosses)
pteridophytes
seedless vascular plants (ferns)
gymnosperms
pollen & naked seeds (cones/coneifers)
angiosperms
flowers & fruits (flowers/flowering plants)
monocots
-one cotyledon
-veins usually parallel
-vascular bundles usually have complex arrangement
-fibrous root system
-floral parts usually in multiples of three
dicots
-two cotyledons
-veins usually reticulate
-vascular bundles are usually arranged in a ring
-taproot usually present
-floral parts usually in multiples of four or five
division of plant kingdom
due to them being eukaryotic, they are divided into two main groups depending on whether or not they contain vascular tissue