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DIVERSITY (phylogeny - evolutionary history of species/group of species…

- - - - clade - ancestor species and all descendants
        monophyletic - equivalent to clade
        paraphyletic - common ancestor and some, not all descendants
        polyphyletic - group of taxa from multiple ancestors
      - shared ancestral character - trait that originated in the ancestor (ex. backbone)
        shared derived character - evolved trait that is unique to a clade (ex. hair in mammals)
      - outgroup - species not included in specific lineage
        ingroup - specific species that is studied
        ex. ingroup: vertebrates, outgroup: insects
- - - - peptidoglycan - polymer, sugars cross w/ short polypeptides, makes up cell walls (rather than cellulose or chitin)
        Gram stain - used to identify and classify bacteria based on cell wall
        Gram-positive - simpler structure, more peptidoglycan
        Gram-negative - less peptidoglycan, have outer membrane made of carbs bonded to lipids
      - capsule - sticky layer of sugar or protein that surrounds cell wall, dense and organized
        slime layer - not organized layer
        fimbriae - hairlike appendages, use to stick to substrate
        pili - appendages pull two cells together, longer and less
    - - taxis - directed movement toward or away from stimulus,
        in half of prokaryotes
        chemotaxis - move towards nutrients (positive) or away from toxic substances (negative)
      - flagella - scattered over whole surface or only 1-2 ends
        
        diffs from eukaryotes: 1/10 width, not covered by plasma membrane, diff molecular comp and mechanics
        
        suggests that flagella in all domains are analogous b/c same function but diff structures
  - - - transformation - DNA from environment change in genotype & phenotype
        transduction - DNA from viruses change genotype & phenotype
      - conjugation - DNA transferred b/w two prokaryotic cells that are temporarily joined
        ex. donor E. coli attach pilus to receiver
        F factor - (fertility), DNA required to form pili & donate DNA in conjugation
        
        F plasmid -
        F factor as a plasmid
        
        F+ cells donate plasmid & convert F- to +
        
        F factor in chromosome:
        
        Hfr cell (sim to F+) donates to F-
        
        DNA exchanged --> recombinant bacteria
        
        how pathogen resists antibiotics:
        
        mutation in chromosome gene
        - R plasmids - carry resistance genes which code for enzymes that destroy antibiotic