MathBench > Measurement

Hemocytometers

Nemo gets tired

minnowsParrotfish are pretty big, and that makes them easy to count.

But parrotfish are obviously not the only thing Nemo needs to count. The next biggest tank is full of guppies. Here's a picture of the middle layer:

As you can see, Nemo's got a problem here -- a lot of counting, and that's just for one layer. And it's only going to get worse as he gets to smaller and smaller organisms, so let's deal with it now.

Or rather, let's listen in as Nemo tries to deal with it.

bored

Nemo: But I don't wanna count every single guppie in there. They reproduce like rabbits, you know.

L. J. Silver: Yo ho ho, and a do-you-want-this-internship-or-not? Counting is what I'm barely paying you to do, so hop to it.

Nemo: Right. No, what I meant is, there has got to be a better way. What if I just count the guppies in 3 of the squares?

L. J. Silver: Then you'd get done a lot faster. And you'd be wrong, ye scurvy bilge rat.

Nemo: But we just need to know the density. I could find the number in those squares and just divide by volume of the squares I counted.

L. J. Silver: Arrr...

Nemo: Watch, it'll be fun....

photo credits: minnows | bored