the DYNAMIC CELL...
  
        some estimates of number of chemical reactions in cells and
        speed of molecular movements inside of cells...

            -  bacterial ribosomes add new aa's @ rate 20 aa/sec
                       bacteria have
  15,000 ribosomes = 300,000 aa/sec or some 1,000 proteins/sec
 
 
            - eukaryotic ribosomes @ 2 aa/sec
                       eukaryotes have over 1 million ribosome = 6,500 proteins/sec

        over 500 molecules pass through each of the 30004000 nuclear pores every second
  
        individual cell of the body make and use on average 10 million ATP/sec
  
        typical enzyme may catalyze 2,500 reactions/sec
 
        a single phospholipid in 1 min may travel breadth of cell
   
        mitochondria in each cell are replaced about every 10 days

                                                                                            Cell Biology animations by john kyrk

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  Scale of Cell (obviously small, but)

        consider that gravity is probably inconsequential...

        instead, electrostatic attractions between molecules and the kinetic energy of motion
                        are the dominant energy forces

        here events take nanseconds and speed is measured in  чm/sec

            -  flagella can move bacteria thru water at 60 cell lengths/sec  = 120 чm/sec (0.0004ft/sec)

            -  Alexander Popov - WR 50M free moves at 1.26 body lengths/sec (7.6 ft/sec)

            -  cheetah, fastest animal known, = 25 body lengths/sec  (115ft/sec)
 

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Cells are truly dynamic...
 
 
   Thousands of chemical reactions occur each second,

    molecules constantly enter and exit across the plasma membrane,

    thousands of proteins are constantly being made,

    cell vesicles move along protein fibers of cytoskeleton,

    cytoskeleton, itself, grows and shrinks continually,

    cells move as a whole flagella or cilia, or cell crawling,

    and motor proteins convert ATP into movement...

 

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