I’m going to get back to the Blogging My Biology Class series, finish out 111, do up 112, and tack on my Zoology class as well. It’s going to be a bit jumpy, though, but on the main series page they’ll all wind up in order by date of the class, rather than date of posting.
For now, my classmate Kristy needs notes from a particular day, so that’s up first.
We started out with a few announcements, a reminder that anyone wanting to do 20 hours of service learning would receive 4 points on their final grade, but that forms were due in to the Student Services office by Friday, 11 September. It’s more than half a letter grade in our 7 point grading system, so it’s worth the price of admission.
Next up was Loggerhead Sea Turtle Nest Sitting down on Topsail Island. There are several nests ready to hatch out any day, and anyone wanting to see this was welcome to head down and hang out. I wound up sitting at a nest on Friday, Saturday, and Sunday nights, several hours each night, but no turtles thus far. I may or may not be able to make it tonight. It’s pouring down the rain, I’ve developed a head cold, and I have an 8 AM English class tomorrow. Of course, if I don’t make it, they’ll hatch tonight just to spite me. Little bastards.
I took a bunch of pictures of other stuff while waiting, and I’ll be posting them here on the blog for your viewing pleasure.
With that, we got back to where we had left off on Wednesday, with the Tissue Level of Organization.
There are several types of tissues in animals, and for our purposes they can be broken down into four groups.
1. Epithelial tissues cover or line structures in the body. The epidermis (the skin) is an example. An interesting little side note here is that it takes about 2 – 4 weeks for a bottom layer of the epidermis to make its way to the top. The top layer gets sloughed off (and becomes the dust in your house and feeds your bedbugs), and the body replaces the bottom layer with fresh epithelial cells. The second layer is now the top layer, etc.
2. Connective tissues have few cells, made up of many fibers. Some examples are cartilage, tendons, ligaments, bone, blood, and adipose (body fat).
3. Muscle Tissue comes in three varieties:
a. Skeletal (a voluntary type of muscle tissue) can have very long, multi-nucleic cells, some of which are over a foot long (in your inner thigh area).
b. Cardiac (involuntary type of muscle tissue) that keep the heart beating without thinking about it, are made up of contractile cells.
c. Smooth (another involuntary type of muscle tissue) which line the gastrointestinal tract and are responsible for peristalsis, the contract/release mechanism that moves food through the bowels.
4. Nervous Tissue responds to stimuli, and is responsible for conducting nerve impulses. Nervous tissue comes in two flavors:
a. Neurons – Really long cells – There is one cell from the spinal cord to the big toe, for instance. I had no idea.
b. Neuroglia Cells – supporting cells that support the neurons.
And at this point we moved into Chapter 4, Taxonomy and Phylogeny of Animals.
We talked a bit about Linnaeus, the Swedish botanist and medical doctor who categorized about 30k species and created the system of binomial nomenclature we use today. The two part, Latin and Latinized scientific names we use to categorize living things is composed of a genus and a specific epithet. Latin is the language of choice because it’s a dead language, thus the meanings of words are not subject to change in the same way words do in a live language like English.
Consider the bald eagle. When named, the word “bald” meant white. It was an obvious choice for the white-headed predatory bird. Today, “bald” means to be without hair or covering. Obviously, the bald eagle has a covering of feathers, so the name doesn’t really apply literally anymore. This sort of thing isn’t such a problem in a language nobody speaks anymore. So the Bald Eagle’s scientific name is Haliaeetus leucocephalus.
We humans, for instance, are categorized as Homo sapiens. Remember that the genus is always capitalized, the specific epithet is never capitalized, and the entire name is always either italicized if in print, or underlined if hand-written.
Side Note: Linnaeus is said to have lost (meaning they died) as much as 1/3 of his students while collecting and categorizing those 30,000 species. He used his students in a way not unlike the way in which a scientist might use his grad students today, except that scientists today mostly try to keep their grad students alive. (…mostly.)
Doc III left us with two more scientific names before the end of the class.
The youpon (similar to a holly): Ilex vomitoria, which breaks down –> Ilex (holly genus) vomit (self explanatory) oria (to eat). So in plain English: “It’s like a holly, eat it, puke.”
Our American Alligators here: Alligator mississippiensis, which should be pretty easy to figure out.
It was a lightish day, and here is where the class ended.
From whence came the art:
The first image is of our textbook, Animal Diversity, by Hickman, Roberts, Keen, Larson, and Eisenhour.
The second image (of a Great Black-backed Gull, Larus marinus) is titled Wary Gull, by me, and is licensed under the Creative Commons Attribution Noncommercial Share Alike license.