Biochemistry WGU c785 Exam Practice Questions and Answers

Biochemistry WGU c785 Exam Practice Questions and Answers Nonenzymatic glycosylation or glycation creates glycoproteins by: 1. Chemical addition of sugars to polypeptides 2. Extracellular synthesis 3. Attaching 20 amino acids 4. Secretion into extracellular matrix - Ans:-1 Nonenzymatic glycosylation or glycation creates glycoproteins by the chemical addition of sugars to polypeptides. Since this type of glycosylation is nonenzymatic, the time and the concentration of sugar control glycosylation. Because people with higher circulating levels of glucose have higher levels of nonenzymatic glycosylation, measurement of the glycosylated hemoglobin A1c is a diagnostic test used to monitor blood sugar levels in persons with diabetes. Which of the following is a 5-carbon sugar? 1. Glucose ©GRACEAMELIA 2024/2025 ACADEMIC YEAR. ALL RIGHTS RESERVED FIRST PUBLISH OCTOBER 2024 Page 2/6 2. Fructose 3. Ribose 4. Sucrose - Ans:-3 Ribose is a pentose, a simple sugar (monosaccharide) that has five carbon atoms per molecule. It is synthesized in the body and obtained in small amounts from consumption of ripe fruits and vegetables. Ribose serves as an energy substrate for the resynthesis of ATP and is a key component of ribonucleic acid (RNA). Deoxyribose, a component of DNA, also is a pentose. The optimum pH of pepsin is: 1. 5 2. 7.1 3. 8.1 4. 2 - Ans:-4 The optimum pH for enzymes varies for different enzymes and even enzymes with similar actions may have different optimal pH based on where they act. For example, trypsin, a digestive enzyme that acts in the small intestine has an optimal pH of 8 while pepsin, which acts in the more acidic milieu of the stomach, has an optimal pH of 2. ©GRACEAMELIA 2024/2025 ACADEMIC YEAR. ALL RIGHTS RESERVED FIRST PUBLISH OCTOBER 2024 Page 3/6 A catabolic enzyme: 1. Joins two or more substances into a larger molecule 2. Cleaves a molecule into two or more parts 3. Inserts a substance between two or more existing molecules 4. Acts as a chemical messenger between amino cells - Ans:-2 A catabolic enzyme engages in destructive metabolism, which involves degrading or breaking down complex molecules into simpler ones with the resulting release of energy. In the body, the breakdown of food in the gastrointestinal tract by a variety of digestive enzymes is an example of a catabolic process. The opposite of catabolism is anabolism. An anabolic enzyme: 1. Cleaves a molecule into two or more parts 2. Inserts a substance between two or more existing molecules 3. Joins two or more substances into a larger molecule 4. Acts as a chemical messenger between amino cells - Ans:-3 Anabolism is the opposite of catabolism and is a set of metabolic pathways that serve to create, construct, or synthesize larger molecules from smaller ones, such as the synthesis of carbohydrates, ©GRACEAMELIA 2024/2025 ACADEMIC YEAR. ALL RIGHTS RESERVED FIRST PUBLISH OCTOBER 2024 Page 4/6 proteins and fatty acids. Anabolic processes consume or require energy rather than releasing energy. Examples of anabolic processes include gluconeogenesis, glyoxylate cycle, and glycosylation. An allosteric enzyme has which of the following properties? 1. It can only operate in an acidic environment, 2. It can only operate in an alkaline environment, 3. It becomes active only when it binds with a specific cofactor, 4. It can function either as a catabolic or anabolic enzyme. - Ans:-3