Blogging My Biology Class 20080919

Biology, Eighth Edition, by Campbell & Reece, et al.

Biology, Eighth Edition, by Campbell & Reece, et al.

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.

Damn.

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.

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Blogging My Biology Class 20080915 Lab

Biology, Eighth Edition, by Campbell & Reece, et al.

Biology, Eighth Edition, by Campbell & Reece, et al.

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.

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Blogging My Biology Class 20080915

Biology, Eighth Edition, by Campbell & Reece, et al.

Biology, Eighth Edition, by Campbell & Reece, et al.

My notes and thoughts from Biology 111, for Monday, September 15, 2008. The entire series can be found here.

The class started with a reminder that the next class period (Wednesday the 17th) would be our first exam.

Then there was a short review of Hydrocarbons generally, and carbohydrates specifically, just to get us back to the place where we had left off.

We picked up this lecture with our discussion of Lipids.

2. Lipids

Triglycerides —> Fats & Oils

glycerol on the left with three fatty acids

Saturated Fat: glycerol on the left with three fatty acids

Glycerol + 3 Fatty Acids

When a glycerol molecule, C3H5(OH)3 (the vertical part on the left of the image), picks up three fatty acids (the long strings of C and H on the right), they combine to form a triglyceride.

Triglycerides are fats and oils. If the long fatty acid chains all remain straight, each carbon bonding with two Hydrogen atoms and its two neighbor Carbon atoms, the triglyceride can pack densely, and thus becomes a solid at room temperature. This is a saturated fat.

Glycerol on the left with three fatty acids. Note the kink in one fatty acid.

Unsaturated Oil: Glycerol on the left with three fatty acids. Note the kink in one fatty acid.

If one or more of the long fatty acids develops a “kink”, ie two Carbons double bond and dump a Hydrogen, the stack can not pack as densely, and thus becomes a liquid at room temperature. This is an unsaturated oil. If there is one kink, it’s a monounsaturated oil, and if more than one, it’s a polyunsaturated oil.

Ta-da. It was kind of cool to suddenly understand the difference between them after having heard the terms for so long in reference to food labels.

We can measure energy in units called calories.

Because of fat’s high percentage of hydrocarbons (all along those fatty acid chains), it has a high caloric content. For comparison, a gram of fat contains 9 calories, while a gram of carbohydrates contains 4 calories. Remember that those Hydrogen – Carbon bonds are high energy content because of the non-polar covalent bond.

(Lecture continues below the fold)

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Blogging My Biology Class 20080912

Biology, Eighth Edition, by Campbell & Reece, et al.

Biology, Eighth Edition, by Campbell & Reece, et al.

My notes and thoughts from Biology 111, for Friday, September 12, 2008. The entire series can be found here.

There are four main classes of organic compounds in living things that Bio 111 is going to cover.

  • Carbohydrates* —> C, H, O
  • Lipids —> C, H, O (sometimes N & P)
  • Proteins* —> C, H, O, N, S
  • Nucleic Acids* —> C, H, O, N, P

* Carbohydrates, Proteins, and Nucleic Acids are Macromolecules, meaning “really honkin’ big”.

1. Carbohydrates – Sugars – all “ose” endings mean “sugar”.

“Carbon Water”

They have a C:H:O ratio of 1:2:1, so the basic carbohydrate formula would be CH2O

a) monosaccharides –> “one sugar” – these are the simple sugars, and contain between 3 – 7 C atoms in them.

A Few Simple Sugars
C Atoms Molecular Formula Group Name
3 C3H6O3 triose
5 C5H10O5 pentose
6 C6H12O6 hexose

(Lecture continues below the fold)

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Blogging My Biology Class 20080910

Biology, Eighth Edition, by Campbell & Reece, et al.

Biology, Eighth Edition, by Campbell & Reece, et al.

My notes and thoughts from Biology 111, for Wednesday, September 10, 2008. The entire series can be found here.

In the last lecture, we had left off with a discussion of pH and [H+]. We started this lecture by finishing up with pH.

Remember that pH is a negative log scale, so as [H+] goes up, pH goes down.

We came to definitions right off the bat.

Acid –> Any substance that increases [H+] of a solution. This is accomplished by donation of H+ ions (p+, since a Hydrogen without an e is just a p+)

HCl —> H+ + Cl

Hydrochloric acid will break down in solution into its constituent parts, thus directly increasing the [H+] and lowering the pH of the solution.

Base –> Any substance that decreases [H+] of a solution. This can be accomplished in one of two ways:

Donation of OH to combine with H+ already in the solution

NaOH —> Na+ + OH —> OH + H+ —> H2O

Oven or drain cleaner, Sodium Hydroxide, will break down in solution into its constituent parts, one of which is a hydroxide ion. The hydroxide ion combines with H+ in the solution to make water, thus lowering [H+] and raising the pH of the solution.

Sucking up of H+

NH3 + H+ —> NH4+

Ammonia, NH3, will pick up an H+ and become NH4+, thus directly decreasing [H+], and raising the pH of the solution.

Then we moved on to Chapter 4: Carbon and the Molecular Diversity of Life

(The rest of the lecture is below the fold)

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Blogging My Biology Class 20080908 Lab

Biology, Eighth Edition, by Campbell & Reece, et al.

Biology, Eighth Edition, by Campbell & Reece, et al.

My notes and thoughts from Biology 111 Lab, for Monday, September 8, 2008. The entire series can be found here.

In this lab we mostly talked about metric system measurements, then went about taking measurements of various things. Honestly, it was pretty mundane stuff for the most part, and I didn’t enjoy this lab nearly as much as the first two, though I understand the necessity of it.

We used rulers, calipers, and a scale to take measurements of wooden blocks, then calculated their volume and surface area.

We measured the room temperature and the temperature of cold tap water and ice water, and water on a boiling plate, as well as skin temperature.

Then, in the most interesting part of the lab, we measured each other’s tibias, and then each other’s heights (as well as a real dead guy’s tibia). We recorded the tibia length and height of everyone in the lab, and for homework we created scatter plots and trend lines with those numbers.

It was pretty straightforward stuff, really, and well… kinda boring except for the dead guy’s bone that Squicky Britches refused to touch. That was a source of mild humor.

From whence came the art:

The first image is of our textbook, Biology, Eighth Edition, by Campbell & Reese et al.

Other images by me and are licensed under the Creative Commons Attribution- NonCommercial- Share Alike 3.0 License.

Weeds and Tares

Nice catch! by Davers @ Flickr

Nice catch! by Davers @ Flickr

So today I attended my first Science Club event. The club keeps a little garden out back of the science building, and it needed weeding.

I stopped by after English class to find Doc all alone, weeding. He pointed out what needed done, what to yank up and what not to, and I set to work. We had the department head pop in and out to lend her hands, and someone who I think is another instructor helped for a while.

It actually turned out to be a nice bit of relaxing time, just chit chatting with Doc about science, the exam, the class, the lab, that sort of thing. We talked about the Thumb and After the Bar Closes, Randi and Dr. PZ, Dover and Brunswick County, Barbara Forrest and Michael Behe, Gould and Dawkins, and Dionaea muscipula, Spanish class and English class, my history with Dr. Bob and my flirtation with L. Ron Hubbard.

It was a great day for it, just the perfect temperature with a perfect breeze, and I was having a good day regarding my neck. I’m kinda glad no one else showed up, in an odd way.

From whence came the art:

That image is titled Nice catch! by Davers, and is licensed by the artist under the Creative Commons Attribution-Noncommercial-No Derivative Works 2.0 license.