00107exam2 - BIOG 001 Practice Exam II for BioG 101 28...

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
BIOG 001 Practice Exam II for BioG 101 28 October 2007 Most of the questions on this exam are drawn from prelims given in BioG 101 in previous years, but it is unlikely that any of these exact questions will appear on this year’s exam. Use this practice test as a way of determining what subject areas you need to review further as you prepare for the exam, and as a rough guide to the types of questions and level of difficulty that you can expect. – LG 1. In the digestion of proteins, the enzyme elastase cuts the polypeptide on the carboxyl side of the amino acid alanine, while the enzyme trypsin cuts on the carboxyl side of either lysine or arginine. Why? a. The shape of the active site for the two enzymes is different. b. Trypsin is a protein but elastase is not. c. One reaction is endergonic but the other is exergonic. d. Only the hydrolysis of the peptide bond of lysine or arginine requires water e. The delta G for the two reactions is different. 2. For the metabolic reaction A + B  C + D, Δ G = -1. You can conclude that: a. the reaction is endergonic. d. at equilibrium, there are more reactants than products. b. the reaction is probably anabolic. e. Two of the above are correct. c. the reaction liberates energy. 3. Which of the following is NOT a characteristic of a typical metabolic pathway in a cell? a. It is a sequence of reactions in which the substrate(s) for one reaction are the products for the next reaction in the series. b. One of the early steps in the pathway is frequently regulated by feedback inhibition by the final product of the pathway. c. Each step in the pathway involves the making or breaking of only a small number of covalent bonds. d. The energy input or release in each step of the pathway is relatively small (on the order of the energy derived from ATP hydrolysis or less). e. The pathway is optimized for utilization of cellular energy and material resources. 4. Of the first four answer choices, which, if any, does not depend on protein conformational changes? a. the catalytic cycle of an enzyme b. allosteric regulation of an enzyme c. the free energy change ( Δ G) of an enzyme-catalyzed reaction d. activation of a protein kinase in a signal transduction pathway e. All of the above depend on protein conformational changes. 5. In considering the coupling of energy derived from ATP hydrolysis to an endergonic enzymatic reaction, which of the following is the most likely mechanistic description of this coupling? a. ATP binds at a regulatory (allosteric site) on the enzyme and puts the enzyme in a more active conformation. b. ATP binds at one active site on the enzyme and the substrates bind at another. Hydrolysis of ATP induces a conformational change in the enzyme that provides the energy for the endergonic reaction at the active site where the substrate is bound. c. ADP and inorganic phosphate bind to the enzyme at one site and the substrate at another. The hydrolysis of ADP and
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 9

00107exam2 - BIOG 001 Practice Exam II for BioG 101 28...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online