Biology exam review questions1. Distinguish between the disciplines known as phylogenetics and taxonomy- Phylogenetics: the study of evolutionary history of related species or other taxonomic groups- Taxonomy: a scientific discipline of how organisms are named and classified2. Construct a generalized phylogenetic tree and label and define representative features: ancestral group, sister taxa, basal group, and polytomy3. What is the operative definition of a clade?Clade: a group of organisms that share a unique derived trait4. Construct a generalized phylogenetic tree where in the following groupings are represented: Monophyletic, paraphyletic, and polyphyleticMonophyletic: Consists of an ancestral species and all of its descendants. Equivalent to aclade.Paraphyletic: consists of an ancestral species and some, but not all of its descendantsPolyphyletic: Includes distantly related species but not their most recent common ancestor5. Distinguish between features of organism that would be interpreted as homologous vs. analogousHomologies: shared ancestry that causes phenotypic and genetic similaritiesAnalogy: similarity between two species that is due to a common ancestor with the same trait6. What are the five kingdoms of life?Monera, Protista, Fungi, Plantae, Animalia7. What is the sequence of taxonomic categories introduces by Linnaeus, from most inclusive to most exclusive?Taxonomic categories introduced by Linnaeus: Hierarchical classification: species, specific-epithet, genus, family, order, class, phylum, kingdom, and domain8. What are the three domains of life?Eukarya, anchaea, bacteria9. Provide at least three features that distinguish archaeans from bacteria. What types of environments do archaeans generally inhabit?Archaean traits: Lack peptidoglycan, some have histones, antibiotic response negativeBacterial traits: Most widespread forms of life on Earth, numerous ecological niches, great metabolic diversityHabitats of archaeans: Hot springs, hyper-saline environments, anaerobic aquatic sediments10. Compare and contrast bacteria cells with eukaryotic cells with respect to: cell wall components, reproduction, flagella structure, arrangement of DNA, and overall sizeBacterial cell wall: cell membrane surrounded by a cell wall, peptidoglycan is the primary wall matrix, mucilaginous capsule is commonly presentBacterial DNA organization: region of concentrated DNA: nucleoid, consists of single, large circular DNA molecule, small independent circular DNA may be present: plasmidsBacterial Flagella: consists of stiff tubular protein: filament, exhibits rotary motion powered by basal apparatus, not membrane boundBacteria reproduction: rapid cell cycle, simple cell division: binary fission < 60 minutesunder good conditions, under unfavorable conditions, endospores are formedEukaryotic flagella: undulipodium, consists of distinctive protein microtubule arry: axoeme, membrane-bound, rooted in cytoplasmEukaryotic cell walls: made from cellulose chemically simpleSize of eukaryotic cell: typically 10-100mm in diameterEukaryotic reproduction: interphase and cell divisionEukaryotic DNA organization: nucleus contains chromosomes and histones11. While bacteria exhibit “simple division”, where in the quantity of DNA remains constant following cell reproduction, why would it be incorrect to say that they undergo mitosis?Bacteria undergo binary fission, meaning that they simply divide in half and this does not involve mitosis12. What cellular features serve to distinguish gram-positive from gram-negative bacteria?Gram-positive bacteria have more peptidoglycan are less toxic to humans. It is less resistant to antibioticsGram-negative bacteria has less peptidoglycan and are structurally more complex. Outer membrane contains lipopolysaccharides13. What is the mode of action of the antibiotic known as penicillin?Eliminates infection caused by bacteria14. Describe differences in the following modes of bacterial metabolism: chemosynthetic, photosynthetic, photoheterotrophic, chemoheterotrophic- Chemosynthetic: obtains energy from chemicals- Photosynthetic: converts light energy to chemical energy- Chemoheterotrophic: require an organic source for energy and carbon- Photoheterotrophic: Perform photosynthesis by require an organic carbon source15. What constraints characterize the process of biological nitrogen fixation?Nitrogen fixation: The conversion of atmospheric nitrogen to ammoniaConversion: N2 to NH4: N2 atmo + 4H+ + energy (ATP) → → NH4 (ammonium)16. Provide an example of a free-living (autotrophic) bacteria capable of nitrogen-fixation. Also provide an example of a mutualistic heterotrophic bacterium that fixes nitrogen.Anaerobic and