Carbohydrates

One of the first  real subject-oriented competencies in my TExES prep book is 004-Structure and function of Carbohydrates, lipids, proteins, and nucleic acids.

Today, I'm just focusing on the Carbohydrates. These are the first big sciency-words that a lot of kids experience in HS Biology. Some of these terms are familiar. They've heard them before, but never truly knew what they meant, or how they fit into the scheme of things.

So I devised this nifty diagram to help clear up some of the cluster.

I'd probably start out with just writing the Carbohydrates header on the board, and discussing monomers and polymers. I'd tell them what they notice about the formula (CH2O)n. How do the numbers of atoms relate? There are 2 hydrogen atoms for each C and O.

From there, we'd start out with the smallest, the monosaccharides. I'd encourage them to come up with clever  ways to remember the 3. For me, it's "Glue a Fruit at a Gala." Then we'd move on to combining these monosaccharides into disaccharides. Again, they would be asked to come up with a familiar little saying to help them remember. All 3 have Glucose. For me, Maltose reminds me of my friend Malorie. She was skinny, despite eating so many sugary things, so a lot of Glucose (Glu + Glu). Lactose 'lacks' the Lu (Glu + Gal). Fructose....toss a Stir FRy (Glu + Suc). There's an endless number of possibilities. Maybe give them this as a homework assignment.

Then we'd go to the polysaccharides. I found it easier to break them up into plant and animal categories, each with one 'structure'(cellulose and chitin) and one 'energy storage' (glycogen and starch).

After this discussion, we'd break up into groups and I'd hand out a paper copy of the chart, and a page of these to each group (as well as scissors and a glue stick)

I'd lable each monosaccharide what it is (glu/fru/gala). Then, they would need to put these next to the appropriate label on the main diagram. To make the disaccharides, they'd need to combine the appropriate monosaccharides, and paste them together on the diagram.

This idea is still a work in progress. I may make it even more complicated, perhaps with a kind of treasure hunt around the class to scavenge the pieces instead of just giving them a paper to cut out. See? constant evolution and re-evaluation. That's what being a teacher is all about.

Well, that and actually...you know...teaching = )