Thursday, April 23, 2009

25) What Are The Building Blocks For Cells?

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glass jar, plastic vial, distilled water, tap water, oscillatoria culture. optional: watch glass, microbalance, bunsen burner?

Lets grow some Oscillatoria. We'll collect some Oscillatoria from a pond. watch it. pretty sophisticated algae! the strands can slide against each other and arrange themselves into sheets to catch the sun! of course they reproduce. notice that there are two different kinds of cells in the strands.

Here are some electron micrographs: pretty complicated inside.

now we'll grow them from scratch. We'll boil a jar to kill all the critters in it wash it out. Next we'll filter some water out, to get all the critters and gunk and parts out of it. boil it to kill any other critters we missed. look at it under a microscope. can't find anything in there? ok, we'll put it in the jar, put in a few strands of Oscillatoria, leave some air, and put it in the sun.

what happens? IT GROWS! what on earth is it building all those parts out of? where does the GREEN come from? It's time for our next level of discovery: CHEMISTRY!

Maybe there is lots of stuff still in the water! we can try to distill the water and use that. does it grow as well?

we can try to grow it in a plastic vial instead of glass, does it grow as well in that?

after we grow a bunch of Oscillatoria, we can weigh it, then dry it out then weigh it again, then burn it. turns into smoke and ash? what's is THAT? try weighing that!here, try burning some wood, how does THAT turn to smoke, and moisture, and ash. Just what IS stuff that it can go through these TRANSFORMATIONS? We have to imagine a whole new level of parts and how they are put together. It certainly is looking like living creatures take each other apart and can even use water, glass and air into VERY SMALL parts to make themselves! what are these parts?

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