Introduction:
“Proteins are large, complex molecules that play many critical roles in the body” (Genetics Home Reference, 2014, p. xx-xx). “They do most of the work in cells and are required for the structure, function, and regulation of the body’s tissues and organs” (Genetics Home Reference, 2014, p. xx-xx). “Proteins are made up of hundreds or thousands of smaller units called amino acids, which are attached to one another in long chains” (Genetics Home Reference , 2014, p. xx-xx). “There are 20 different types of amino acids that can be combined to make a protein” (Genetics Home Reference, 2014, p. xx-xx). “The sequence of amino acids determines each protein’s unique 3-dimensional structure and its specific function” (Genetics Home Reference, 2014, p. xx-xx).
“Proteins are complex molecules made up of carbon, hydrogen, oxygen and nitrogen (sometimes sulphur and phosphorus)” (TutorVista.com, 2014, p. xx-xx). There are four levels to protein structure, there is primary structure, secondary structure, tertiary structure, and lastly quaternary structure. Each structure has a unique shape.
“The primary structure of a protein is its amino acid sequence” (Sadava, 2011, p. 44). “Amino Acid monomers are joined forming polypeptide chains” (Sadava, 2011, p. 45). The primary structure is composed of one of the strongest bonds, covalent bonds. The secondary structure however is made of weaker bonds, which are hydrogen bonds. Secondary structure can create two shapes. Either the alpha helix, or the beta pleated sheets. “The (alpha) helix is a right-handed coil that turns in the same direction as a standard wood screw” (Sadava, 2011, p. 46). “The coiling results from hydrogen bonds that form between the δ+ hydrogen of the N-H of one amino...
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...onomers took longer to travel down the gel, thus resting at the top most bands, illustrated by Figure 2 and proved by Figure 1.
References
Genetics Home Reference (2014, February 10). What are proteins and what do they do? - Genetics Home Reference. Retrieved from http://ghr.nlm.nih.gov/handbook/howgeneswork/protein
Life Science Core at UCLA, Martin, L., Chen, K., Johnson, L., Foley, R., & Murotake, R. (2005). Analysis of Protein Size and Subunit Composition Using SDS- Polyacrylamide Gel Electrophoresis. Los Angeles, CA.
Sadava, D. E. (2011). Life: The science of biology (9th ed.). Sunderland, Mass: Sinauer Associates.
TutorVista.com (2014). Proteins, Composition of Proteins, Classification of Proteins | Tutorvista.com. Retrieved from http://www.tutorvista.com/content/biology/biology-iv/animal-nutrition/proteins.php#
The shape of the protein chains that produce the building blocks and other structures used in life is mostly determined by weak chemical bonds that are easily broken and remade. These chains can shorten, lengthen, and change shape in response to the input or withdrawal of energy. The changes in the chains alter the shape of the protein and can also alter its function or cause it to become either active or inactive. The ATP molecule can bond to one part of a... ... middle of paper ... ...
The primary structure is the sequence of amino acids that make up a polypeptide chain. 20 different amino acids are found in proteins. The exact order of the amino acids in a specific protein is the primary sequence for that protein. [IMAGE] [IMAGE]Protein secondary structure refers to regular, repeated patterns of folding of the protein backbone. The two most common folding patterns are the alpha helix and the beta sheet.
The Lives of a Cell: Notes of a Biology Watcher by Lewis Thomas consists of short, insightful essays that offer the reader a different perspective on the world and on ourselves.
Phelan, J. (2011). What Is Life? A Guide To Biology with Physiology. New York: Peter Marshall.
"A Cell 's Life: The Immortal Life of Henrietta Lacks." Issues in Science and Technology 26.4 (2010): 87. Academic OneFile. Web. 11 Nov. 2016.
...ionships." Philosophical Transactions of the Royal Society B: Biological Sciences. University of Cambridge, 6 Nov. 2006. Web. 24 Mar. 2014.
3 Leicht B. G., McAllister B.F. 2014. Foundations of Biology 1411, 2nd edition. Southlake, TX: Fountainhead Press. Pp 137, 163-168, 177-180,
Abstract/Summary: “Proteins account for more than 50% of the dry weight of most cells, and they are instrumental in almost everything organisms do” (Campbell, 1999). The significance of proteins to the continuation of our biological systems is undeniable, and a study of how to quantify proteins seems an appropriate introduction to our studies of biology. In order to study proteins we must first know how to separate then quantify the amount using basic principles of experimental design such as a standard curve. In this experiment we wish to quantify the amount of previously extracted protein by measuring the absorbance of the unknown amount and determining its concentration by overlaying it against a standard curve of the absorbance of known concentrations of the protein. We used the dye agent Bradford Protein Assay to get an absorbance of 0.078, 0.143, 0.393, 0.473, and 0.527 at the protein’s respective concentrations of 0.28, 0.56, 0.84, 1.12, and 1.40 mg/mL. When a best-fit line was applied to the standard curve, and the absorbance of our unknown concentration (0.317 A) plotted, we estimated a concentration of around 0.84 mg/mL of protein. Our calculations indicated a quantity of 168 mg of protein, which was an approximately 8.96% yield of the projected 1875 mg that was expected. Errors that may have led to this small yield percentage may have stemmed from our previous lab and our initial attempts to extract the desired amount of protein.
Protein have connection with amino acid to help in functions of: skin, muscle, hair and bones
Web. The Web. The Web. 11 February 2014 “Biology: Evolution”. The New York Public Library Science Desk Reference.
"Within a single subunit [polypeptide chain], contiguous portions of the polypeptide chain frequently fold into compact, local semi-independent units called domains." - Richardson, 1981
Proteins are considered to be the most versatile macromolecules in a living system. This is because they serve crucial functions in all biological processes. Proteins are linear polymers, and they are made up of monomer units that are called amino acids. The sequence of the amino acids linked together is referred to as the primary structure. A protein will spontaneously fold up into a 3D shape caused by the hydrogen bonding of amino acids near each other. This 3D structure is determined by the sequence of the amino acids. The 3D structure is referred to as the secondary structure. There is also a tertiary structure, which is formed by the long-range interactions of the amino acids. Protein function is directly dependent on this 3D structure.
J. Losos, K. Mason, S. Singer, based on the work of P. Raven, & G. Johnson, Biology, 8th ed., (McGraw-Hill Education (Asia), Singapore, 2008), pp. 994-995.