MODERN CLASSIFICATION Linnaeus Binomial nomenclature Taxon (taxa) Phylogenetics- the tracing of evolutionary relationships
EARLY HISTORY OF LIFE Solar system~ 12 billion years ago (bya) Earth~ 4.5 bya Life~ 3.5 Prokaryotes~ 3.5 to 2.0 bya Oxygen accumulation~ 2.7 bya photosynthetic cyanobacteria Eukaryotic life~ 2.1 bya Muticelluar eukaryotes~ 1.2 bya Animal diversity~ 543 mya Land colonization~ 500 mya
BACTERIA Domain: Bacteria Domain: Archaea Prokaryotic- no membrane-bound organelles, microscopic Shape 1. Cocci (sphere) 2. Bacilli (rod) 3. Helical (spiral) Archaea Vs. Eubacteria DOMAIN ARCHAEA No peptidoglycan Do not respond to antibiotics Extremophiles 3 main groups: methanogens, extreme halophiles, extreme thermophiles DOMAIN EUBACTERIA Peptidoglycan in cell walls Growth inhibited by antibiotics 5 main groups: spirochetes, chlamydias, gram+, cyanobacteria, proteobacteria Prokaryotes Decomposers Unlock organics from corpses and waste products Symbiosis Symbiont/host mutualism (+, +) parasitism (+, -) commensalism (+, 0) Disease Opportunistic: Normal residents of host; cause illness when defenses are weakened Exotoxins: Bacterial proteins that can produce disease w/o the prokaryote present (botulism) Endotoxins: Components of gram - membranes (Salmonella)
DOMAIN EUKARYA Nucleus Membrane-bound organelles Larger in size than prokaryotic cells Fungus, plant, and animal cells Kingdom Protista Ingestive: (animal-like); protozoa Absorptive: (fungus-like) Photosynthetic: (plant-like);alga Kingdom Plantae Bryophytes (mosses), Pteridophytes (ferns), Gymnosperms (pines and conifers) Angiosperms (flowering plants) Plants: multicellular, eukaryotic, photosynthetic autotrophs Terrestrial colonization: Vascular tissue The seed The flower
Monocots: 1 embryonic seed leaf (lilies, palms, grasses, grain crops) Dicots: 2 embryonic seed leaves (roses, peas, sunflowers, oaks, maples) Vascular tissue refinement: vessel elements/fiber cells Kingdom Fungi Heterotrophic by absorption (exoenzymes) Decomposers (saprobes), parasites, mutualistic symbionts (lichens) Hyphae: body filaments Mycelium: network of hyphae Chitin cell walls (polysaccharide) Phy: Chytridiomycota aquatic fungi; chytrids lineage closest to protists (flagella) Phy: Zygomycota •Rhizopus (food mold) •Mycorrhizae: mutualistic with plant roots •Zygosporangia: resistant structure (freezing and drying) Phy.: Ascomycota •sac fungi • yeasts, truffles, morels, •asci: sexual spores •conidia: asexual spores Phy.: Basidiomycota • club fungus •mushrooms, puffballs, shelf fungus, rusts •basidiocarps: produce sexual spores Kingdom Animalia Heterotrophic Most are mobile Ingestion followed by digestion Multicellular (most have tissues) Lack cell walls Sexual reproduction 35 phyla- most are marine
Gymnosperms Cone-bearing plants Lack enclosed chambers (ovaries) for seeds Ovules and seeds develop on specialized leaves called sporophylls Ginkgo, cycads, and conifers All are “evergreens” Needle-shaped leaves Vascular tissue refinement: tracheids~ water conducting and supportive element of xylem Angiosperms Most diverse and geographically widespread of all plants “Flowering plants”(Phy: Anthophyta)
