I have posted to this grp. before and have always had luck in
getting responses to my questions so here it goes again..
I am studying for my micro final and I need some clarifications:
1) Phototaxis: when bacteria go into darkness, they stop, and reverse
direction back into light. Called shock response. My book says this is
different from chemotaxis but doesn't give details. They both are
behavioral responses, are they not? The only diff. I see is that in
chemotaxis, there is a physical agent that actually binds to the cell to
influence flagellar rotation. Light obviously can't bind to anything.
Is this the difference they are talking about?
2) Reducing bacteria: reduce compounds using external e- donors and ATP.
This reduction results in a PMF being generated which allows for ATP
synthesis. This new ATP can be used in the reduction of other compounds
(replaces ATP used in step 1). Is this statement correct?
3) Chemolithotrophs oxidize inorganic cmpds. to get e- for reducing power
and the synthesis of ATP. These 2 things then reduce CO2 to
polysaccharides. How can this be called aerobic respiration by
microorganisms when CO2 is converted to polysaccharides. I thought
respiration was the reduction of polysaccharide to CO2?
Sorry this is so long. Thanks in advance for your help. This is my last
final before graduation on the 18th!!!!
B.S biology UNC- Chapel Hill