If you look under the surface of the pond, you see a very busy ecosystem indeed! There are plants, fish and insects, and those are just the visible organisms. There are way more microscopic organisms than big ones, which I'll save for a future post.
|Green algae growing just below the surface of our pond.|
|Interconnected strands of green algae pulled up from under the surface.|
|Green algae out of the water.|
I looked at the algae from our pond using a microscope that magnified what I saw by a factor of 100. In the picture below, you can see the cell wall between adjacent algal cells, just above the pointer. Cell walls are rigid structures made of cellulose (a strong, rigid molecule), and they give plant cells their shape. Paper is made by starting with plant material and getting rid of everything but the cellulose, meaning that paper is essentially squished, dried plant cell walls.
|The pointer rests on a filament of green algae. A broken alga releases its cell contents. 100x|
Below is another view under the microscope, with one normal filament and one filament with shrunken cell contents. The chloroplasts and other structures have been compressed into a central structure in each cell. The strange filament may be undergoing reproduction or it could be stressed, but either way, you can see the beautiful cylindrical shape of each individual cell.
|Shrunken cell contents in the lower filament allow you to see the cell walls. The round object is an air bubble. 100x|