Biology Lab

Instructions In this lab, you will build edible models of a representative macromolecule of each of the groups. Please view this tutorial on macromolecules before you begin. To review, you should interact with the macromolecules tutorial linked above. It will open in a new window. There are 4 classes of macromolecules: sugars, lipids, proteins and nucleic acids. 1. Sugars- sugars are composed of monomers (building blocks) called monosaccharides. One example a monosaccharide with 6 carbon atoms is glucose. Starch is an example of a polysaccharide. In order to make starch, a cell connects glucose monomers together by the condensation reaction (sometimes called dehydration synthesis), water would have been released from the reaction. Choose a food to represent glucose monomers and connect 6 of them together end to end. This long chain represents starch. 2. Lipids- some lipids are used to store energy. There are several types of monomers that can be connected together to form different lipids. Glycerol and fatty acids are the two most common monomers, but phosphate groups can also serve as monomers. Triglycerides (fats) are polymers composed of a glycerol molecule and three fatty acids. Choose a short skinny food to represent glycerol. Next add three fatty acids (each fatty acid should be represented as a long skinny food) to the side of the food that represents glycerol. You have just used the condensation reaction to make a triglyceride (fat).(Make sure the food you choose for the models is proportional to the actual size of the molecules) Phospholipids are the major components of cell membranes. To make a phospholipid, start with a glycerol (a short skinny food) and add two fatty acids to one side of the bottom of it and add a small round food (a phosphate) to the top end of the other side of it. 3. Proteins- proteins are sometimes called “polypeptides”. Proteins are made up of monomers called amino acids. There are twenty different types of amino acids that a cell can choose from when making a protein. The special type of covalent bond that holds the amino acids together is called a peptide bond. Enzymes are proteins with a special shapes that help them to do their job just as a tool’s shape must match its purpose. Choose food that has several different color variations to represent amino acids. Place 10 of these small foods end to end in a long chain. This long chain represents a protein. 4. Nucleic acids- Nucleic acids (DNA and RNA) store to information for the order of the amino acids. For this reason, DNA is sometimes called a cell’s recipe book or blueprint. The monomers that make up the nucleic acids are called nucleotides. Each nucleotide is composed of three parts- a sugar, a phosphate and a nitrogen base. There are four different nitrogen bases= A, T, G and C. Your DNA model will roughly resemble a ladder, with the rungs of the ladder composed of two parts side by side(the complementary bases) and the sides alternating between sugars and phosphates DNA is double stranded, the two strands are complementary to each other and are held together by hydrogen bonds between the complementary bases = A-T and G-C. Use the foods you chose previously for the sugar and the phosphate. Place a sugar, phosphate, sugar, phosphate in a row. In a parallel row, place a sugar, phosphate, sugar and a phosphate. Choose a food with 4 different variations to represent the nitrogen bases A, T, G and C. Place two of these foods with different variations between two of the sugars of the sugar phosphate rows and place the other two variations between the other 2 variations of the food that represents the nitrogen base. Make sure you illustrate the correct base-pairing Note: Visually impaired individuals may need a sighted assistant to increase their interaction with this lab. • How your models will be graded 9 points maximum 0 1 2 3 Clarity and file size The file size is over 3.0 MB and or less than half of the labels are easily readable The file size is over 1.5 MB and at least half of the labels are readable The file size is over 750 KB but less than 1.5 MB and all labels are readable The file size is appropriate and all labels are readable Accuracy and completeness Less than 60% of the parts are labeled and/or correct 60-80% of the parts are labeled and/or present 80%-99% of the parts are labeled correctly and/or present 100% of the parts are present and labeled correctly Neatness and Creativity The model is sloppy The model is neat or creative but not both The model is moderately neat and creative The model is very neat and creative • Plagiarism If a student who submits an entire photo which is identical to one submitted by another student or includes a single model that matches another student's model will receive a zero on the entire macromolecules assignment. • Edible macromolecules assignment- sugar, fat and phospholipid photo You will submit a digital photograph of your edible sugar and lipid models here. The photo must be clear, in .jpg format and must be less than 750KB (0.75MB) in size. Instructions: Arrange your models as follows, then take a single picture. The sugar model should be at the top of the picture, and the phospholipid model should be at the bottom. Be sure to label all the parts of each molecule (label the monosaccharides in the sugar, the glycerol, phosphate and fatty acids in the phospholipid). You can arrange the models on a piece of paper and write the labels on the sheet of paper and use arrows to point to the structures. Be sure that the labels are clear and readable in your photo. Your name and the date must be written on the paper and clearly visible. To submit the file, click the assignment title above and then browse for/attach the .jpg files and click "submit". The assignment will be graded within 48 hours. • Protein and DNA model photo You will submit a digital photograph of your edible protein and DNA models here. The photo must be clear, in .jpg format and must be less than 750KB (0.75MB) in size. Instructions: Arrange your models as follows, then take a single picture of them together. The protein model should be at the top of the photo (there must be at least 8 amino acids present) and the DNA model should be at the bottom. Be sure to label the amino acids in the protein and fold or coil the protein a bit so that it shows some secondary structure. DNA model: label nucleotide, sugar, phosphate, and the 4 different bases (adenine, thymine, cytosine and guanine). Your name and the date must be written on the piece of paper. To submit the file, click the assignment title above and then browse for/attach the .jpg files and click "submit".