One Quiz Under the Belt & Another Duplicated Lab

It turns out my confidence for yesterday's quiz was not misguided, I believe I did really well. If I made any errors it was only through haste. For some reason I had it in my head that I was taking a really long time to finish, and that everyone was waiting just for me. So I started scribbling as fast as I could, and I think I may have switched two very similar words around...which was a totally stupid, preventable mistake. Hopefully I didn't actually make that error, but if I did, well that's the way the cookie crumbles & it'll teach me to slow down.

I'm very disappointed in yesterday's lab; it was another that I have already done, and not a very interesting one at that. We had to get two deshelled eggs (when you put a whole egg in vinegar to soak, the shell dissolves completely and you're left with only the membanous egg) and place them in two different solutions; one a hypertonic solution & the other a hypotonic solution. We then weighed the eggs at various intervals to see if they had taken on or lost water weight. The point of this lab is to show how different types of solutions effect the diffusion of water in and out of a membrane. On the plus side, we did do a slight variation in that we also looked at sheep's blood under the microscope. We prepared three different slides; on the first we put the blood in an isotonic solution, thus the blood cells retained their normal shape. On the second slide we put the blood in a hypertonic solution in which the cells noticeably shriveled (crenated). On the third slide we put the blood in a hypotonic solution in which the cells swelled and eventually burst (lysed). Overall, this was much more interesting than weighing the eggs.

Sorry, no pictures of this one! I didn't have to do any drawings.