Please answer all questions and provide explanations if possible 1. Glycoprotein
ID: 202254 • Letter: P
Question
Please answer all questions and provide explanations if possible
1. Glycoproteins are proteins modified with sugars. Which amino acid residues are sugars 2. 3. 4. commonly linked to? What are the chemical and structural differences between cellulose and glycogen? What are the properties of the C1 anomeric carbon of the pyranose form of glucose? What is the type of lipid depicted below? What would it be called using the different nomenclatures discussed in class? 3 5. What is the backbone scaffold (platform) of a phospholipid? 6. Consider the three (I-III) fatty acids below. From lowest to highest, what is the most likely order of their melting temperatures (Tm)? I. docosanoate, CH3(CH2)20CO2H II. heptadecanoate, CH3(CH2)isCO2H III. cis-A*-heptadecenoate, CH3(CH2)7CH-CH(CH2) 6CO2HExplanation / Answer
1) Serine, Threonine, and Aspargine
Addition of sugars to the proteins called glycosylation which occurs in the endoplasmic reticulum. N-linked glycosylation occurs in the asparagine and O-linked glycosylation occurs in the serine and threonine
2) Cellulose is a structural polysaccharide made up of glucose molecules which are joined by the beta 1,4 linkages and glycogen is storage polysaccharide in animals made up of glucose units which are joined by the alpha 1,4 linkages. Cellulose had straight chain structure but glycogen with branched chain structure. Cellulose in involved in the making of body structure but glycogen involved in the production of energy.
3) the carbonyl carbon of an open chain form of a sugar molecule is called anomeric carbon. On the basis of configuration around the anomeric carbon atom, the D and L isomers are determined.
4) The given molecule is called omega-6 polyunsaturated fatty acid and named as Icosa-5,8,11,14-tetradecanoic acid
The omega fatty acids prevent the development of cancer, cardiovascular diseases, Inflammation and Developmental disabilities. Omega3 fatty acids are three types 1. docosahexaenoic acid 2. -linolenic acid and eicosapentaenoic acid
5) The plasma membrane is composed of Phospholipids, proteins, and cholesterol. The Phospholipids are most abundant amphipathic molecules form the cell membranes. The backbone of phospholipid molecule made up of a glycerol molecule, two fatty acids, and a phosphate group which is modified by an alcohol (e.g. choline).
6) The melting temperature dependent upon the no of double bonds/unsaturation and carbon chain length. If the molecule is more saturated and with long carbon chain it has a higher melting temperature. Based this information the order is I (20 carbons)>II (15 carbons)>III (unsaturated)