Macromolecules Lab Report

The purpose of this lab is to learn how to properly conduct two different macromolecules test, the nucleic test and protein test in order to identify whether four different types of food, contain proteins and nucleic acid. The way an individual can determine if a specific macromolecule is present is by conducting qualitative tests, which allows an individual to determine whether a certain macromolecule is present by observing the color change. Additionally, for statistical analysis semi-quantitative tests will be conducted as well to determine the relative amount of a macromolecule that is present in the food based on the color change. (Dooley 20). Moreover, before conducting this experiment an individual must determine the positive and negative

control for each macromolecule test. For instance, the positive control for the protein test will be pepsin, since pepsin is a known solution that contains protein, while the positive control in the nucleic acid test will be DNA since DNA is a nucleic acid, thus it has to contain this macromolecule. The purpose of the positive control is to compare the color change of this control to the color change of the other solutions in order to determine if the macromolecule being tested is present in the solution. Meanwhile the negative control for both experiments will always be water since it does not contain any macromolecule.
Hence, this experiment mainly is about two significant macromolecules that are found in food.

Macromolecules are define as large molecules of structures found in living organisms. There are four types of macromolecules, which are proteins, carbohydrate, nucleic acid, and lipids also known as fats. Carbohydrates, proteins, and nucleic acids are made of monomers, which are structural units that eventually attached together to form polymers (Dooley 20). For instance, proteins are made of amino acids, which are monomers. In addition, it has a complex structure, which consist of four different levels, primary, secondary, tertiary, and quaternary. The first structure of protein is the primary structure, which is the sequence of amino acid, while in the secondary structure alpha and beta helices are formed. The structure, in which a protein becomes active, is in the tertiary structure, which is where polypeptide subunits fold. Meanwhile, only certain proteins have the quaternary structure, which is when, more than one polypeptide folds. Proteins are prominent macromolecules mainly because of their numerous functions. For instance, proteins are known for increasing the rate of reactions due to that enzymes are a type of protein. In addition, they are a form of defense mechanism such as they attack pathogens, which cause diseases. In other words, scientists study and gain more insight on certain illness and how to prevent them by using proteins. For example, in a recent study,

scientists developed a new form of technology to study HIV proteins, which is beneficial because it can help them have a better understanding of what causes this deadly virus, thus eventually perhaps leading to a cure or even more sufficient ways to prevent this virus (Whiteman).
Moreover, like proteins nucleic acids have monomers as well which are known as nucleotide. Nucleic acids contain purine bases such as adenine (A) and guanine (G), pyrimidine bases that are cytosine (C), uracil (U) and thymine (T), five carbon sugars and phosphate groups (Holcomb). In addition, there are two distinct types of nucleic acid, which are DNA, and RNA, both that are different in numerous ways. For instance, unlike RNA, DNA does not have a hydroxyl group, thus making it less reactive than RNA. However, while RNA is more reactive, DNA is more stable mainly because it forms a double helix, while RNA is unable to form a double helix and has only one strand (Freeman 60). Additionally, another way RNA and DNA differ is because RNA does not contain thymine, on the contrary it has uracil instead. While, a similarity between DNA and RNA is that they help cells create proteins as well as replicate. Overall, the hypothesis of this experiment is that all the food being tested for nucleic acid and protein will contain both macromolecules. Furthermore, in order for a color change to occur during both test specific indicator are required, for instance for protein a biuret reagent is necessary, while a dische’s reagent is required in order to observe color change.