lecture 5.txt

  1. lecture 5
    cell envelope
  2. this structure allows somet thigns to pass through the membrane iwout energy expenditure and others can�t
    semipermeable membrane
  3. __ are channels in membrane that allow water to pass without energy expenditure
  4. these are proteins with a gate that control flow of ions
    gated channels
  5. these are large complex transport which allows protein conglomerates to pass with energy
  6. _ is the tendency for water to flow according to its gradient
  7. this is a higher concentration of solute
  8. this is a lower concentration of solute
  9. equal concentrations across a membrane is called
  10. _ is the bursting of a cell due to hypotonic environment
  11. tendency for h2o to flow across membrane and cause pressure; occurs in bacteria due to cell wall
    turgor pressure
  12. shrinking of cells due to hypertonic environment is called
    plasmolysis (crenation)
  13. process of making solutes inside a cell to prevent plasmolysis
  14. particle formed to prevent plasmolysis
  15. separation of ions that creates a gradient of charge and concentration
    proton motive force
  16. what is the formulat for pmf
    voltage potential + concentration gradient
  17. when the membrane is slightly negative its called
    membrane potential
  18. when there are more protons outside of the cell
    there is a proton gradient
  19. _ causes electrons to flow to do waste-like pump pumping H+ out
    respiratory chain
  20. _ changes shape when hit by light and flips electrons to outside of membrane
  21. _ forms cell wall with sugar and amino acid
  22. 4 amino acids in which the third amino acid must have 2 amino groups
    peptide side chains
  23. _ connects 2 strands of peptidoglycan connected by pentaglycine bridge
    peptide crosslinking
  24. process of making crosslinks of peptidoglycan with peptide bonds
  25. _ makes glycosidic bonds between peptidoglycan
  26. polymer of phosphate and usgar that sticks out of cell; provides phosphate surface and protection from digestive enzymes
    techoic acid
  27. phosphate and sugar that anchors peptidoglycan to cell membrane
    lipoteichoic acid
  28. transport channels through outer membrane which allows things into the periplasm
  29. only present in G- bacteria, asymmetric with LPS on outside
    outer membrane
  30. _are large�molecules�consisting of a�lipid�and a�polysaccharide�joined by a�covalent bond; they are found in the�outer membrane�of�Gram-negative�bacteria, act as�endotoxins�and elicit strong�immune responses�in animals
  31. a�lipid�component of an�endotoxin�held responsible for�toxicity�of�Gram-negative�bacteria. It is the innermost of the three regions of thelipopolysaccharide�(LPS, also called�endotoxin) molecule, and its�hydrophobic�nature allows it to anchor the LPS to the outer membrane
    lipid A
  32. O antigens are the immunodominant part of the lipopolysaccharide molecule in the intact bacterial cell.
    • O-antigen
    • \
    • waxy layer in mycobacterium from 60-90 degrees C
    • mycolic acid
  33. organism which lacks cell wall and therefore lacks a particular shape
Card Set
lecture 5.txt
Micro 221 lecture 5