So, I’m a little stir crazy, and kind of brain fried, and looking for something interesting but non-school-related to do…
My notes and thoughts from Biology 111, for Monday, September 22, 2008. The entire series can be found here.
Before we get to the actual lecture, there’s something I need to address here.
While taking notes, it is often helpful and even necessary to draw little diagrams and pictures, many of which I reproduce in this series by digital means.
This is often simpler, neater, and more helpful than just scanning pages of notes from my notebook.
Until now, it’s really not made much of a difference, but in this lecture we begin drawing diagrams of cell structure, and while it’s not terribly difficult to do digitally, when drawing them in a notebook it is imperative for accuracy to understand the proper method for drawing a cell. It is a skill which requires a great deal of practice.
Chromosomes and various proteins for example, can be very complicated, and drawing them incorrectly can lead to gross misunderstandings and disaster for the student. To help prevent this, I’ve created a digital animation of the proper method for drawing a chromosome inside a prokaryotic cell. The method employed here can be extended and extrapolations to eukaryotic cell diagramming should not be difficult.
The method, along with this lecture, is below the fold.
My notes and thoughts from Biology 111, for Friday, September 19, 2008. The entire series can be found here.
As we took our first exam on Wednesday, September 17, there was no lecture for that day.
We took the first part of class to go over the exam results. I had left the exam feeling very good, figuring I was unsure about and may have missed two or three questions. Turns out, I missed eight.
Out of 64 students in 3 sections, the highest score was a 91, the lowest a 29, and the median 67. I scored an 88.
Doc said not to sweat it too much, as the first exam is the one everyone does a little less well on, unfamiliar territory, etc., and he drops the lowest exam score.
I was rather surprised at about 5 of my 8 incorrect answers, thinking to myself, “What the hell were you thinking???? You know better than that!!!” I really pulled some dumb answers from out of my butt to very simple answers.
One of my incorrect answers though, was the molecular formula of maltose (two glucose molecules bonded together). Now, without thinking, I simply answered with double the formula of glucose, stupidly forgetting to subtract the water molecule from the hydrolysis synthesis that is required to form maltose from two glucose molecules (or any disaccharide from two monosaccharides).
Hence the unforgettable graphic I made subsequently. After making that animation, I will never repeat that mistake.
After going over the exam, we moved on to Chapter 6 – A Tour of the Cell.
Notes for that brief lecture are below the fold.
My notes and thoughts from Biology 111 Lab, for Monday, September 15, 2008. The entire series can be found here.
In this lab, we learned to use reagents to test for the presence of proteins, starch, and sugars, using distilled water as a negative control.
Since distilled water should be straight H2O and nothing else, each time we did a test, we could see what the reagent did in solution without the presence of whatever it was we were testing for.
We worked in groups, and our group consisted of four students.
A. In the first experiment, we tested for the presence of proteins with Biuret reagent, a highly corrosive blue/purply substance. Our Lab Manual and Doc each warned us about its potential hazards, safety precautions, and what to do if we got it on our skin.
We marked four test tubes at the 1 cm level.
1) Test tube 1 we filled to the mark with distilled water. We then added about 5 drops of Biuret reagent. The water turned light blue. This was our negative control to which we could compare the other tubes when the Biuret reagent was added.
Lab continues, below the fold.