Princeton Review exams Actual Questions With Complete Questions And Answers.

A parallel-plate capacitor (with a vacuum in between the plates) is connected to a battery. In Step 1, the distance between the plates is increased while the battery is still attached. In Step 2, the battery is disconnected and a dielectric is placed in between the plates. Which of the following is true about the change of potential energy in each of the steps? A. ΔPE1 > 0 and ΔPE2 > 0 B. ΔPE1 > 0 and ΔPE2 < 0 C. ΔPE1 < 0 and ΔPE2 > 0 D. ΔPE1 < 0 and ΔPE2 < 0 - correct answer D. The equation for capacitance is C = κε0A / d, where κ is the dielectric constant (κ > 1), ε0 is a constant, A is the area of the plates and d is the separation between plates. In Step 1, d increases, therefore C decreases. In Step 2, κ increases, therefore C increases. The potential energy stored in a capacitor can be written as (1/2)CV2 or Q2 / 2C. In Step 1, the battery remains attached which means that V remains constant, so use the equation for PE with the V term. In that case, PE ∝ C, so decreasing C means the potential energy must therefore decrease. This eliminates choices A and B. In Step 2, the battery is disconnected, which means that Q remains constant, so use the equation for PE with the Q term. In that case, PE ∝ 1 / C, so increasing C means the potential energy must therefore decrease. The correct answer is choice D. The Ka for the first ionization of sulfurous acid (1.7 × 10-2) is significantly larger than the Ka for the second ionization (6.4 × 10-8). A likely explanation for this is that: A. the electronegativity of the remaining hydrogen atom increases after the first hydrogen ion has been removed. B. the second ionization can only take place if the first ionization proceeds to completion. C. neutral hydrogen is difficult to ionize in aqueous solution. D. the remaining hydrogen atom experiences greater electrostatic attraction after the loss of the first hydrogen ion. - correct answer D. After loss of the first proton, the remaining hydrogen is bound to a negatively-charged molecule. Electrostatic attraction between this remaining hydrogen and the negatively-charged molecule would disfavor loss of the second proton, resulting in a smaller K. Therefore, K2 << K1. Which of the following accurately lists the composition of the endoplasmic reticulum, phosphofructokinase and alanine, respectively? A. Double membrane surrounding a lumen, amino acids linked together by covalent proteolytic bonds, four different groups on a chiral Alpha carbon. B. Single membrane surrounding a lumen, amino acids linked together by hydrogen bonds, four different groups on a chiral Alpha carbon. C. Single membrane surrounding a lumen, amino acids linked together by covalent peptide bonds, four different groups on a chiral Alpha carbon. D. Single membrane surrounding a lumen, amino acids linked together by covalent peptide bonds, three different groups on a chiral Alpha carbon. - correct answer C. The endoplasmic reticulum is an organelle with a single membrane surrounding a lumen (eliminate choice A). Phosphofructokinase is an enzyme of glycolysis, and so is a protein made of amino acids linked together by covalent peptide bonds (choice B is wrong). Alanine is a chiral amino acid, and so has four different groups on a chiral alpha carbon (another reason to eliminate choice D). Choice C provides an accurate description and is correct. Which of the following best describes how the brain determines the location of a sound? A. The angle of the sound wave, with respect to the eardrum, allows the brain to determine the location of the sound. B. Sound waves reach the ear closest to the source of the sound first, and this difference in timing allows the brain to determine the location of the sound. C. The angle of the sound wave, with respect to the auditory hair cells, allows the brain to determine the location of the sound. D. Sound waves closer to the source have a higher frequency, and this difference in frequency allows the brain to determine the location of the sound. - correct answer B. The angle of the sound wave with respect to the ear is not pertinent to determining the location of the sound (choices A and C can be eliminated). Sound waves reach the ear closest to the source of the sound first, and the further ear second. This time gap allows the brain to determine the location of the sound (choice B is correct). Choice D is incorrect; the frequency of the sound is not relevant to determining the location, nor is there a difference from one ear to the next. Eukaryotic cells use reciprocal regulation to make sure β-oxidation and fatty acid biosynthesis do not occur at the same time. This is accomplished by malonyl CoA, which inhibits the carnitine shuttle required to transfer activated fatty acids from the cytoplasm to the mitochondrial matrix. Each of the following is a true statement EXCEPT: A. both β-oxidation and fatty acid biosynthesis occur in four steps; fatty acid biosynthesis involves elongation, two redox reactions and a dehydration. B. β-oxidation involves the reduction of both FAD and NAD+; fatty acid biosynthesis oxidizes two NADPH (generated by the pentose phosphate pathway) to two NADP+. C. because of this reciprocal regulation, both β-oxidation and fatty acid biosynthesis occur in the mitochondrial matrix. D. β-oxidation generates acetyl CoA, while fatty acid biosynthesis uses malonyl CoA, which is made from acetyl CoA by acetyl CoA carboxylase. - correct answer C. Choices A, B and D are true statements. Choice C is false (and the correct answer); β-oxidation occurs in the mitochondrial matrix and fatty acid biosynthesis occurs in the cytoplasm. The serotonin transporter (or SERT) removes serotonin from the synaptic cleft and recycles it back into the presynaptic cell. It thus terminates the effects of serotonin and this mechanism has been targeted in treatments for alcoholism, clinical depression, obsessive-compulsive disorder, and hypertension. SERT spans the plasma membrane 12 times and is also a: A. glycosylated phospholipid, with both hydrophobic and hydrophilic regions. B. peptide chain with at least four levels of protein structure, held together by disulphide and peptide bonds. C. protein with twelve hydrophobic domains, none of which contain the amino acid proline and at least some of which contain Beta-sheets stabilized by covalent bonds. D. protein with twelve transmembrane domains, each of which is an Alpha-helix with no proline and external hydrophobic residues, stabilized by hydrogen bonds - correct answer D. Membrane transport is mediated by proteins, not phospholipids (eliminate choice A). All proteins have at least three levels of protein structure, but only some have quaternary structure. There is no information in the question stem to support the fact that SERT contains more than one peptide chain (eliminate choice B). Transmembrane domains are alpha-helices with external hydrophobic residues. They cannot contain proline because of its secondary amine structure. Both alpha-helices and beta-sheets are stabilized by hydrogen bonds, not covalent bonds (eliminate choice C, choice D is correct). Which of the following inhibitors would have no effect on the slope of a Lineweaver-Burk plot? A. Competitive Inhibitor B. Uncompetitive Inhibitor C. Noncompetitive Inhibitor D. Mixed Inhibitor - correct answer B. As the slope of the Lineweaver-Burk plot is Km/Vmax, the correct answer is an inhibitor that has the same effect on both Km and Vmax. An uncompetitive inhibitor leads to an equal decrease in the both the Km and Vmax, leading to a series of parallel lines on a Lineweaver-Burk plot (choice B is correct). Competitive, noncompetitive, and mixed inhibitions would all affect the slope of a Lineweaver-Burk plot (choices A, C, and D are wrong). At physiological pH, the amino acid with the formula C4H7NO4 has: A. two deprotonated carboxylic acid groups and is ketogenic. B. one deprotonated carboxylic acid group and is ketogenic. C. two deprotonated carboxylic acid groups and is glucogenic. Correct Answer D. one deprotonated carboxylic acid group and is glucogenic. - correct answer C. This is a typical two-by-two question. Since none of the pictured amino acids in Figures 1 or 2 have four oxygen atoms, the amino acid with the formula C4H7NO4 must be glucogenic (choices A and B can be eliminated). Only aspartic acid and glutamic acid have four oxygen atoms, two of them found in the carboxylic acid end of the backbone, and two of them found in the carboxylic acid end of the side chain, so this question must be asking about one of these amino acids. In actual fact, aspartic acid has the formula C4H7NO4, but you don't need to figure this out to answer the question. At physiological pH (about 7.4), both the carboxylic acid end of the amino acid and the side chain COOH will be deprotonated. This is because physiological pH is above the pKa values for these acidic protons (carboxyl pKa is approximately 2, and the R-group pKa is approximately 4). Thus, aspartic acid will actually be in its aspartate form, and will have two deprotonated carboxylic acid groups at physiological pH (choice C is correct and choice D is wrong). Can glucogenic amino acids be converted into glucose? A. Yes: pyruvate and oxaloacetate can be converted directly into glyceraldehyde-3-P, which is a major intermediate in both gluconeogenesis and glycolysis. B. Yes: pyruvate and Krebs cycle intermediates can be converted into oxaloacetate, then phosphoenolpyruvate, which can enter gluconeogenesis. Correct Answer C. No: pyruvate and Krebs cycle intermediates are formed as part of glucose breakdown and this process is important to generate ATP for the cell. D. No: glucose is obtained from the diet and stored in the liver; it cannot be made as a new molecule because cellular respiration has several steps with a -ΔG. - correct answer B. This is a typical two by two question. The passage says that glucogenic amino acids are broken down into citric acid cycle intermediates or pyruvate. The Krebs cycle regenerates oxaloacetate (OAA), and in the first step of gluconeogenesis, pyruvate is also converted into OAA (by the enzyme pyruvate carboxylase). OAA is converted into phosphoenolpyruvate (PEP) by the enzyme phosphoenolpyruvate carboxykinase (or PEPCK). Gluconeogenesis can then continue to run, and will generate glucose from these non-carbohydrate precursor molecules (choice B is correct). Although glyceraldehyde-3-P is a major intermediate in both gluconeogenesis and glycolysis, pyruvate and oxaloacetate cannot be converted directly into this molecule (choice A is incorrect). Both choices C and D are incorrect because they start with "No"; as discussed above, glucogenic amino acids can be converted into glucose (choices C and D are wrong). 1-Methylcyclohexanol reacts with HBr to form 1-bromo-1-methylcyclohexane. The mechanism for this reaction is likely to be an: A. SN1 reaction. Correct Answer B. SN2 reaction. C. Nucleophilic addition. D. Addition-elimination. - correct answer A. Since no double bonds are formed or broken, this must be a substitution reaction (eliminate choices C and D). Since the hydroxyl in the starting material is on a tertiary carbon atom, the mechanism cannot occur by a bimolecular pathway (eliminate choice B.) The protonated OH group (under acidic conditions) will leave as water to yield a tertiary carbocation, which will be attacked by the bromide ion to give the product. In a facultative anaerobe, which of the following processes occurs under both aerobic and anaerobic conditions? A. Fermentation B. Krebs cycle C. Glycolysis Correct Answer D. Oxidative phosphorylation - correct answer C. A facultative anaerobe can survive through fermentation when oxygen is not available but will use oxidative respiration when oxygen is available. Glycolysis will occur under both aerobic conditions (in which case the pyruvate will go on to enter the Krebs cycle as acetyl-CoA) and under anaerobic conditions (fermentation reduces pyruvate to alcohol or lactate), so choice C is correct. Fermentation occurs only in anaerobic conditions (choice A is wrong), while the Krebs cycle and oxidative phosphorylation can occur only in aerobic conditions (choices B and D are wrong). Increased intermolecular attractions cause the ratio PV/(RT) to decline because individual molecules: A. eventually combine with other molecules, decreasing the number of particles in the container. B. lose kinetic energy to potential energy and strike the side of the container with less force. Correct Answer C. increase in speed due to electron repulsion and strike the side of the container with increased force. D. transfer electrons during collisions with other molecules in the container. - correct answer B. Intermolecular attractions increase the potential energy between molecules, decreasing their kinetic energy. Note that the molecules do not undergo any reactions, eliminating choices A and D. Choice C is incorrect because intermolecular attractions do not result in electron repulsion. The episodic buffer allowed participants to: A. remember the instructions of the OLG task. B. form a visual picture of the video clip while recording response options. C. apply experience learned in prior games in order to generate options. D. avoid confusing the contents of one clip with those of another. - correct answer C. According to Baddeley, the working memory system is composed of four parts. The visuospatial sketchpad is a short-term visual store, the phonological loop is a short-term auditory store, the central executive is responsible for task-switching, and the episodic buffer integrates information from the other three systems and from long-term memory. An example of the contribution of the episodic buffer, therefore, is the recollection and application of prior game experience (choice C is correct). The episodic buffer is not directly responsible for the internal organization of experience (choice D is wrong). Rehearsal of verbal instructions would be the province of the phonological loop (choice A is wrong), while short-term visual memory of the video clips would be the province of the visuospatial sketchpad (choice B is wrong). One of the modifications that Milgram made to his original shock experiment was to test the possible effects of conformity on obedience. The basic experiment tests the conditions under which a research subject, the "teacher", will administer an electric shock to the "learner" (a confederate member of the research team). The teacher receives instructions from an authoritative "experimenter" (a research team member) to administer the shock under certain circumstances. Which of the following experimental modifications would in fact test for the effects of conformity on obedience? Adding another teacher (a confederate) to the shock administration room Adding a window to the room so that the teacher can see the learner Increasing the proximity of the teacher to the learner A. I only B. II only C. I and II only D. II and III only - correct answer A. To assess the possible effects of conformity on obedience, one must determine whether and to what extent subjects conform their behavior to the actions of others who appear to be similarly situated (i.e., other "teachers") when determinig whether or not to obey the experimenter who instructs them to administer shocks. Item I is true: adding another confederate teacher to the shock administration room would test whether the naive subject would conform to the actions of the other "teacher" when determining whether or not to obey. Item II is false: adding a window to the room wherein the learner will receive the shock would not test for the effects of conformity on obedience because it would not include a similarly situated figure (choices B and C can be eliminated). Item III is false: similarly, merely increasing the proximity of the teacher to the learner would only test obedience, as there is no other person present to whose behavior the subjects might conform their actions (choice D can be eliminated, choice A is correct). The iron law of oligarchy: A. asserts that, because of the constant struggle between the labor class and the ownership class, democracy will be inevitably replaced by socialism. B. explains how formal social norms are codified into laws. C. describes the process whereby tasks are broken down into component parts to be completed by different workers in an organization. D. suggests that democracy is not possible in large groups or organizations - correct answer D. The iron law of oligarchy is a theory in sociology that states that regardless of how democratic an organization is, all organizations will eventually and inevitably end up with a majority of the power in the hands of a few, thus leading to an oligarchy. The iron law of oligarchy suggests that democracy is practically and theoretically impossible, particularly in large and complex organizations (choice D is correct). Karl Marx asserted that, because of the constant struggle between the labor class and the ownership class, capitalism (not democracy) will be inevitably replaced by socialism (choice A is wrong), but this has nothing to do with the iron law of oligarchy. The iron law of oligarchy does not explain how formal social norms are codified into laws (choice B is wrong). Rationalization, which is a major component of bureaucracy, describes the process whereby tasks are broken down into component parts to be completed by different workers in an organization (choice C is wrong). Theorists using the conflict perspective to address questions of health, illness, and medicine are LEAST likely to consider: A. the commodification of health care delivery. B. the presence of disparities in health and health care. C. the power of professionals in patient-provider relationships. D. the dependence of medical institutions on profit. - correct answer C. Each of the main sociological perspectives—structural functionalism, conflict theory, and symbolic interactionism—is expected to approach health and health care differently. The conflict theory approach considers the competition for limited resources. According to this theory, limited resources, a negative result of capitalism, cause inequalities and power differentials in society. This concept can be extended to the medical institution. Furthermore, Karl Marx, the founding conflict theorist, focused on the internal tensions produced in capitalistic societies. Thus, it is expected that the conflict perspective would consider the commodification of health care and the dependence of institutions on profit (choices A and D can be eliminated). Health care can thus be purchased and sold in a marketplace, which allows those with resources and influence to control pertinent decisions, thus maintaining inequalities. Furthermore, these social inequalities determine the distribution of health care access and resources. Thus, it is expected that the conflict perspective would consider the resultant disparities in health and health care (choice B can be eliminated). However, while conflict theorists are interested in the creation and maintenance of power differentials, as proponents of a macro-sociological perspective, this interest is applied to social structures as a whole. The patient-provider relationship would perhaps be of more interest to symbolic interactionists, as symbolic interactionism is a micro-level perspective focused on the transfer of information through communication between individuals (choice C is not an expected focus of conflict theorists and is the correct answer). Furthermore, it is possible that a power differential is inherent in the provider-patient relationship as a result of the expertise required How would the functionalist sociological perspective view chronic illness? The distribution of chronic diseases reflects social patterns in the distribution of wealth and power. Disease is a form of deviant behavior because it interrupts the contributions of people to their societies. The medical profession is important in regulating the production capabilities of those with chronic conditions. A. II only B. III only C. I and II only D. II and III only - correct answer D. Structural functionalism is centered on the concept of society as a living organism. According to this sociological model, each individual social structure has a distinct purpose that is important for the function of the greater society. Item I is false: health disparities as a result of social inequalities in the distribution of resources is of interest to conflict theorists, not to functionalists (choice C can be eliminated). Conflict theory is centered on the concept of so