Unit 2 Reflection

This unit was titled the Chemistry of Life. As one can probably tell from the title, the unit was about the basic chemistry necessary for learning biology. In this unit, we learned about the properties of water, different types of chemical bonds, and the four different macromolecules along with their uses and structures. Some labs we did include the sweetness lab, the enzyme virtual lab, and the cheese lab. The sweetness lab demonstrated the relationship between the structure of a carbohydrate and the taste. Both the cheese and enzyme virtual labs gave us an idea of the conditions in which enzymes work best. We were pretty successful with our sweetness lab and enzyme lab, but the cheese lab had quite a few setbacks. We had a pretty severe time restraint, so if the milk didn't curdle within 15 minutes, we had to call it a Did Not Curdle. Also, there was a lot of ambiguity surrounding what the word "curdle" actually meant. It was hard to tell how much curdling would actually count as "curdling" because of this ambiguity.
From this unit, I definitely learned a lot of content as well as skills. I learned, contrary to my previous intuition, that not all sugars are that sweet. Also, I had assumed in the past that since acids were good at breaking things down, enzymes would be most effective in an acidic environment. However, I was clearly wrong, and I now know that enzymes work best in a neutral pH and at room temperature. I also never knew that a pipette had markings for volume, but now that I do know this, I will put it to good use to make my measurements much more accurate in the future.
However, I still have many unanswered questions and more I want to learn about. Like for I example, I know that enzymes work best in a neutral pH and room temperature, but when it comes to curdling milk, how come they are more effective in a warm, acidic environment? Also, as we did do experiments regarding carbohydrates and proteins, I am still curious to see if we will work with lipids and nucleic acids, the two macromolecules that we haven't touched on much outside of the vodcasts. Sometimes, these experiments make me think about my own diet, and I still feel like there are many foods that don't fall into any of those categories. However, maybe as I learn more in the future, those burning questions will finally be answered.

Sweetness Lab

In this lab, we asked the question: How does the structure of a carbohydrate affect its taste (sweetness)? We found that monosaccharides and disaccharides tended to be on the sweeter side while the polysaccharides were pretty plain tasting. Monosaccharides were very sweet, disaccharides were medium-sweet, and the polysaccharides were tasteless. The average degree of sweetness among the monosaccharides was about 123. For the disaccharides, it was 45, and for the polysaccharides, it was 0. This data supported my claim because I predicted that fructose (a monosaccharide) would be very sweet. Indeed. it was the very sweetest.

Carbohydrate structure and the amount of rings could affect how they are used by organisms. A more simple carbohydrate would be broken down very quickly, but have a smaller energy release while a more complex carbohydrate might take longer to be broken down, but have quite a bit of energy released.

The testers didn't give each sample the same rating. Of course, this makes sense because different people haven't different senses of taste. For example, Marie rated many of the sugars with a higher degree of sweetness than I did. This is most likely because I have a dull sense of taste, since a I eat a lot of spicy stuff. Marie, on the other hand, doesn't eat spicy foods.

Taste buds cause humans to taste sweetness as well as other flavors. However, the amount of taste buds varies from person to person. The more taste buds a person has, the more sensitive their sense of taste is. In the example above, it would be logical to conclude that Marie has more taste buds than me.

What Is Biology?

Jean Lab

                    In this lab, we asked the question: What concentration of bleach is best to fade the color out of new denim material in 10 minutes without visible damage to the fabric? We found that unless the concentration was at least 50%, the solution would literally do nothing. As seen in the data table, all trials for fabric damage and color change resulted in 0's for concentrations less than 50%. Since 50% had a pretty subtle change (average 1) and 100% had a bit of fabric damage, we can conclude that the right concentration is probably somewhere between the two concentration. Our hypothesis was right because indeed there does exist a concentration of bleach that can fade jeans perfectly.  

                   While our hypothesis was supported by our data, there could have been errors due to inexact timing of submerging and washing out of bleach. These timing errors could've affected the results because some samples that were submerged longer would be more faded than others. Also, we noticed that our bleach was a lot less yellow than other bleaches so maybe our bleach was not pure. This could've affected our results by making the jeans a lot less faded than they should've been. In the future, we could have everyone in the class start at the same time and maybe we could have everybody use bleach from the same bleach bottle.

                   This lab was done to demonstrate how difference concentrations of bleach could yield different results on the color and quality of denim jeans. Also, as the very first lab of the year, the lab was probably also for helping students understand how an experiment is carried out. I can relate this experiment to one time when I was doing the laundry, I used too much bleach. The results were not pretty. Based on my experience from this lab, I now know how to bleach my jeans. Although this experiment isn't very applicable to biology, it still helped me understand the steps of executing an experiment.