PROTEINS AND NUCLEIC ACIDS
Qn. Which two of the four macromolecules do you believe to be the most important for life? Give evidence to support your suggestion (include a full description of the macromolecules you describe both in terms of structure and function) Introduction
All the four macromolecules=lipids, proteins, carbohydrates and nucleic acids= are essential for the functioning of an organism's body (Campbell, biology). They work hand in hand to help us survive. For example, Lipids are an immediate energy source. ATP, for example, is used by the body when in energy deficit. Proteins are needed to form muscles and bones. Carbohydrates are the main energy source for the body. Without this energy, we would not be able to function. And finally, Nucleic Acids contain the DNA required to make us who we are. Without DNA, we would not be alive. It is obvious that without these four macromolecules we would not exist. However from the four of them, I believe proteins and nucleic acids to be the most important as they both carry out major functions in our bodies. PROTEIN
Structure of proteins
Proteins are polymers composed of 20 amino acids which are joined together by a peptide bond which forms a polypeptide chain. A polypeptide coiled into a specific 3-dimensional shape makes a protein. (Campbell, biology, pp78) Proteins are divided into two classes: fibrous and globular proteins. Globular proteins are compact, soluble, and spherical in shape, while Fibrous proteins are elongated and insoluble. Globular and fibrous proteins may sometimes display different types of protein structure. These structure types are; primary, secondary and tertiary structure (Campbell biology, pp82-83) 1. Primary structure
Primary structure refers to the unique order of amino acids to form a protein.Protein is constructed from 20 amino acids. All amino acids have a hydrogen atom (H), carboxyl group (-COOH), and an amino R group. The R group is the one that determines the...
Bibliography: Campbell Reece, Biology, Eighth edition, Benjamin Cummings, 2008.
Janice R. Herman. Protein and the body. Oklahoma Cooperative Extension Service.
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