Human Population -- Population Puzzle

Human Population Growth:  POPULATION PUZZLE – Extra Credit

Bacteria multiply by division.  One bacterium becomes two.  Then two divide into four; the four divide into eight, and so on.  For a certain strain of bacteria, the time for this division process is one minute (the doubling time).  If you put one bacterium in a bottle at 11:00 pm, by midnight the entire bottle will be full.

1.  At what time will the bottle be half full?

2.  Suppose you could be a bacterium in this bottle.  At what time would you first realize that you were running out of space?  Explain your response.

3.  Suppose that at 11:58 some bacteria realize that they are running out of  space in the bottle.  So they launch a search for new bottles.  They look far and wide.  Finally, offshore in the Arctic Ocean, they find three new empty bottles.  Great sighs of relief come from all the bacteria.  This is three times the number of bottles they’ve known.  Surely, they think, their space problems are over.  Is that so? 


4.  Since their space resources have quadrupled, how long can their growth continue?

(HINT:  How full is each bottle, including the original, at:

            11:58 pm

            11:59 pm

            12:00 am

            12:01 am

            12:02 am

            12:03 am