In our June 2018 News & Views issue, we asked Science teachers and Burkies to share examples of work their class work. Below is a project sample.
TEACHER: Lindley van der Linde
Biology can become heavily focused on new terms and concepts. In the fall the Biology class covers what could be considered a dry unit on biologically important molecules including carbohydrates, lipids, amino acids and nucleic acids. This unit covers what it means to be an organic molecule, introduces the functional groups that attach to a carbon chain to make basic building blocks (monomers), and is students’ first exposure to connecting monomers to make long chains of molecules called polymers. Students conduct a concurrent lab introducing them to the concept of an indicator, a positive or negative test for the presence of monomers or polymers. By using Benedict’s solution, students see firsthand how the indicator (which is normally blue) turns green in the presence of disaccharides (like lactose), and orange in the presence of monosaccharides (like glucose), and therefore is a positive test for a monosaccharide. Thus, students learn the names and structures of building blocks of their own bodies. The simplest way for athletes to get energy using cellular respiration is to break down long chains of carbohydrates (a polymer) into glucose (a monomer).
Lani Ashnault ’21
This year in biology, the knowledge I have retained from hands-on experience is extensive. We have done many labs in the Science Center in the past eight months. Personally, I believe that the most engaging experiments were at the beginning of the year. These consisted of testing organic compounds for their contents. One of our first labs was Benedict’s test. Benedict’s reagent turns from its original color (turquoise) to green, yellow, or orange, depending on what reducing sugar it is introduced to. Therefore, if you mixed Benedicts with a polysaccharide, then it would stay blue. If mixed with a disaccharide, it would turn green. When you have a monosaccharide and add Benedicts to it, it would turn orange. Following Benedict’s test, we performed an iodine test. Plants store glucose as polysaccharide starch. When we put iodine in the liquids, the ones that turned black, or blue presented presence of starch. These experiments helped me view the roles of organic compounds based on their contents, and how it can affect the outcome of experiments when in contact with different reagents.
Dan Gillis ’20
Throughout our biology class this year, we have learned about many interesting topics. After studying the structure of eukaryotic cells at the beginning of the year, our class learned the roles of certain organelles within eukaryotic cells. The chloroplasts and the mitochondria were the most interesting organelles because they support the basis of life. In the chloroplast of plant cells, photosynthesis occurs. During photosynthesis, carbon dioxide and water, transform into glucose and oxygen with the help of sunlight. In this process, glucose and oxygen are products of the reaction. In the mitochondria of animal cells, cellular respiration occurs. During cellular respiration, oxygen and glucose, are converted into energy with the products being carbon dioxide and water. Photosynthesis and cellular respiration are two very important biological processes that use each other’s byproducts as reactants in order to support life on earth. The mitochondria and the chloroplast are interesting and vital organelles because they are the place where cellular respiration and photosynthesis occur. As an assignment for Lindley, Danny Proffit and I made a video which compares a cell and its organelles to a ski mountain.
Sammi Trudeau ’20
In Biology, we have been studying genetics and patterns of inheritance. Through Punnett squares and the rule of multiplication, we tracked our personal genetic histories and the genetic lines of European royalty. Understanding basic rules, names, and patterns of genes provided helpful background knowledge when it came to analysis and predictions. It was interesting to see the traits that are determined by genetics. The most amusing part was watching people try to roll their tongues when it wasn’t part of their genetic makeup. As the winter concludes, we are looking forward to more hands-on activities and labs.