Blueprint Full length 3 Question review

a solution with an H+ concentration of 10^−4 M will have a pH of _______

4

What is the size of the prokaryotic ribosome?

70S (50S + 30S)

What is the size of a eukaryotic ribosome?

80S (60S + 40S)

a solution with an OH− concentration of 10^−9 M will have a pOH of _______

9

If a modern portable defibrillator uses a 12 V battery and a 20 μF capacitor, what is the total charge stored on the plates of the capacitor? A. 0.24 mC B. 0.48 mC C. 24 mC D. 24 C

A. 0.24 mC Capacitance (C, measured in farads) is the amount of charge, q, stored per volt, and is expressed as C = q/V. This means that charge (q) = VC. The capacitance is given as 20 x 10-6 F. Substituting the voltage (12 V) and capacitance into the equation gives us the charge (in coulombs). (20 x 10-6 F)(1.2 x 101 V) = 24 x 10-5 C = 2.4 x 10-4 C = 0.24 x 10-3 C = 0.24 mC Remember that making the exponent greater means the coefficient must be made smaller by the same factor.

The electrical resistance of dry skin is 100 kΩ, but it can be lowered to 20 Ω if the electrode contact area with the skin is large and a conducting gel is used. If Vmax of the defibrillator is 500 V and lasts for 0.01 s, what is the maximum possible current delivered to the heart during defibrillation? A. 2.5 × 10^1 A B. 2.5 × 10^-2 A C. 5.0 × 10^-2 A D. 5 A

A. 2.5 × 101 A We are given R, V, and time, and the question asks us to determine current (charge/time, or C/s). Recall that Ohm's law, V = IR, does not have a time dependence Since I = V/R and the question asks for the maximum current, we need to use the smallest available resistance. I =V/R = (500 V) / (20 Ω) = (50) / (2) = 25 amps = 2.5 × 10^1 A

If the Gibbs free energy of the liquid-crystalline phase for an aqueous dispersion of DPCC and raffinose is 17.9 kcal/mol, which of the following values is nearest the Gibbs free energy of the associated gel phase? A. 3.5 kcal/mol B. 32.3 kcal/mol C. 566.1 kcal/mol D. 601.9 kcal/mol

A. 3.5 kcal/mol By rearranging Equation 1, ∆G = Gl - Gg, an expression for the Gibbs free energy of the gel phase may be found: Gg = Gl - ∆G. The Gibbs free energy change for the phase transition of raffinose is given by ∆G = ∆H - T∆S. Substituting thermodynamic values from Table 1: ∆G = (16.0 kcal/mol) - [(3.15 x 102 K)(5.05 x 10-3 kcal/K•mol)] ∆G = 16.0 kcal/mol - 1.60 kcal/mol = 14.4 kcal/mol Substituting into the rearranged form of Equation 1: Gg = Gl - ∆G = 17.9 kcal/mol - 14.4 kcal/mol = 3.5 kcal/mol. Notice that the correct answer can be chosen without completing the final calculation.

Which of the following best explains the tumor reduction capacities of the isotopes observed in the study? Note: GKS-CO reduced the tumor more initially, but 3 and 12 month follow ups show that tumor size was reduced more overall by GKS-X GKS-X has a half life of 1 year. GKS-CO has a half life of 5 years. A. GKS-X emits more radiation per unit time, causing more cell death. B. GKS-X emits narrower radiation streams that target the tumor. C. The Co isotope in GKS-Co has a longer half-life than X in GKS-X. D. GKS-Co does not emit sufficient radiation to kill tumor cells.

A. GKS-X emits more radiation per unit time, causing more cell death. Table 1 shows that GKS-X is more effective at reducing tumor size (as shown by its lower RTV values over time). We need to choose a statement that can explain this improved ability of GKS-X to kill cancer cells. We must think about the differences between X and 60Co, chief among them the five fold difference in half-life. Because X has a shorter half-life, it is logical that it would release more radiation in the same period of time because it undergoes decay more quickly. This higher dose of radiation would kill more cells, cancerous and non-cancerous, leading to a larger reduction in tumor size and more undesirable side effects

Which of the following is LEAST likely to be observed in a patient experiencing hyperventilation? A. Hypoxia B. Net exhalation of CO2 C. Increased blood pH D. Increased hemoglobin O2 affinity

A. Hypoxia This question asks us to determine the effects of hyperventilation. During hyperventilation, there is a loss of CO2 and an increase in O2 in the blood. Hypoxia is another term for oxygen deprivation, which is the opposite of what would occur here. The others: B. Net exhalation of CO2 During hyperventilation, CO2 is lost due to excess exhalation. C. Increased blood pH Loss of CO2 corresponds with increased blood pH. Losing CO2 is roughly equivalent to losing acid due to the action of carbonic anhydrase in the bicarbonate buffer system. D. Increased hemoglobin O2 affinity Loss of CO2 corresponds with increased hemoglobin affinity for O2. This is the same as saying the hemoglobin binding curve shifts left.

Which of the following would have likely lessened the effects observed in the study? I. One guard stating that the treatment of prisoners was too harsh II. Giving information that past participants acted in similarly harsh ways III. Assigning roles based on a personality profile A. I only B. II only C. I and II only D. I and III only

A. I only Compliance was shown to be severely weakened when just one person disagreed with the group (I).

Which of the following statements is NOT true concerning the element that it describes? A. Lithium has the second-largest atomic radius in period 2. B. Iodine has the highest electronegativity in period 5. C. Iron is a transition element. D. Neodymium is a rare earth element.

A. Lithium has the second-largest atomic radius in period 2. Lithium (atomic symbol Li) is in Group 1, which is sometimes called the alkali metal group. Atomic radii decrease from left to right across a row in the periodic table. Thus, lithium has the largest (not the second largest) atomic radius in period 2, so this answer is false, and choice A is the correct answer to this NOT question.

Atrial fibrillation is the most common heart arrhythmia, causing palpitations, fainting and chest pain. According to the information in the passage, what is most likely to be observed in the ECG during atrial fibrillation? A. Missing P waves and an irregular rate B. Complete absence of P waves and a regular rate C. Complete absence of R waves and an irregular rate D. Missing R waves and a regular rate

A. Missing P waves and an irregular rate An arrhythmia is an irregular time period between heartbeats, not necessarily a rate that is too slow or too fast. Since the question asks about atrial fibrillation, and the P wave is attributed to contraction of the atria, the correct answer should show the P wave being affected. This does not mean that the atria are not contracting at all (eliminate choice B), but it indicates that blood is not efficiently being pumped from the atria to the ventricles.

When an odorant molecule binds to olfactory receptors, the cell transduces the information into an electrical signal that travels to the brain for processing. Which of the following accurately describes the state of the voltage-gated channels on this cell during the relative refractory period? A. Na+ channels are activated, and K+ channels are activated. B. Na+ channels are inactivated, and K+ channels are activated. C. Na+ channels are activated, and K+ channels are inactivated. D. Na+ channels are inactivated, and K+ channels are inactivated.

A. Na+ channels are activated, and K+ channels are activated. First, we need to understand the difference between the absolute and relative refractory periods. The absolute refractory period lasts nearly the entire duration of an action potential, during which time a second action potential cannot be generated. During this time, voltage-gated sodium channels are "inactivated." If this term is not familiar, note that voltage-gated sodium channels have two gates that must be open for sodium to flow inward and depolarize the cell membrane. If the "inactivation gate" is closed, the channels are inactivated. If the inactivation gate is open but the activation gate is closed, the channel is "de-inactivated" — it isn't inactivated, but it is not yet open either. This "de-inactivation" occurs once the action potential nears its end and the membrane voltage becomes sufficiently low (generally during the hyperpolarization phase). At this time, the inactivation gate opens and the activation gate closes. Since the channel is not inactivated, a stimulus could theoretically produce an action potential, but since the cell is hyperpolarized, this stimulus would need to be larger than normal. This interval is termed the relative refractory period, which is what this question asks about. At this time, again, sodium channels are de-inactivated; potassium channels are still activated, allowing potassium to continue flowing out of the cell to finish the action potential.

Based on passage information, medication for which other disorder might increase symptoms of schizophrenia? Note: the passage states that schizophrenia is believed to be caused partially by an overabundance of dopamine. A. Parkinson's disease B. Major depressive disorder C. Antisocial personality disorder D. Dissociative personality disorder

A. Parkinson's disease The passage states that schizophrenia is thought to be at least partially caused by dopamine overactivity. Parkinson's disease, in contrast, is caused by insufficient dopamine transmission in the substantia nigra. Therefore, treatments for Parkinson's include medications designed to increase dopamine levels. Too large a dose and/or administration of such medications to susceptible individuals might therefore increase the risk of experiencing symptoms of schizophrenia.

When student A talks about their financial struggles with a classmate, the classmate has an immediate negative reaction about having a classmate who is from a low socioeconomic background. Which phenomenon does this represent? A. Prejudice B. Stereotype threat C. Discrimination D. Availability heuristic

A. Prejudice Prejudice reflects an unjustifiable attitude toward a group of people and often involves a negative emotional reaction. The classmate's immediate reaction to student A (because they perceived the student as poor) is indicative of prejudice.

Which hormone is responsible for aiding in the secretion of IgA in breast milk? A. Prolactin B. Calcitonin C. Epinephrine D. LH

A. Prolactin Prolactin is the hormone responsible for stimulating the mammary glands to produce milk.

Which of the following types of electromagnetic radiation would have the shortest wavelength? A. Radiation that ejects an electron from an sp orbital B. Radiation that ejects an electron from an sp2 orbital C. Radiation that ejects an electron from an sp3 orbital D. Radiation that excites but does not eject an electron from an sp3 orbital

A. Radiation that ejects an electron from an sp orbital This question asks us about the wavelength of electromagnetic radiation (EMR) that ejects an electron from an atom. Shorter-wavelength EMR (such as γ rays) carries much more energy than longer-wavelength EMR (such as radio waves). Therefore, we must look for the answer choice that involves the highest-energy EMR. The closer an electron is to the nucleus, the harder it is to eject. Because sp-hybridized orbitals have the most s character of all of the answer choices, they contain the electrons that are the most difficult to eject Remember: Shorter wavelength questions are actually asking about which produces the most energy.

What is directly responsible for allowing the alveoli to remain inflated during exhalation? A. Surfactant that decreases surface tension B. Surfactant that increases surface tension C. Negative intrapleural pressure D. Positive pressure in the pleural cavity

A. Surfactant that decreases surface tension Surfactant in the lungs is responsible for lowering the surface tension and preventing alveolar collapse during expiration.

A woman visits her doctor to receive medical test results. While the patient anxiously waits, the doctor stops in to shake hands before going to analyze the results. The patient mistakes the handshake as a cold dismissal rather than a warm greeting. This is an example of which sociological theory? A. Symbolic interactionism B. Social constructionism C. Exchange-rational theory D. Feminist theory

A. Symbolic interactionism In symbolic interactionism, a symbol is something we assign meaning to, and that most members of society collectively understand. Symbols can include gestures (such as handshakes), rituals, or other social practices. Symbolic interactionism focuses on understanding how these symbols are used by individuals to ascribe meaning and interact with other members of society. In this case, the symbol (handshake) was given a meaning (cold dismissal) by the patient during an interaction with her doctor. Other: B. Social constructionism Social constructionism examines the development of jointly constructed understandings of the world. It assumes that understanding, significance, and meaning are developed not separately within the individual, but in coordination with other human beings. C. Exchange-rational theory Exchange-rational theory posits that patterns of behavior in societies reflect the choices made by individuals as they try to maximize their benefits and minimize their costs.

Which of the following cellular features is a structural component of the blood-brain barrier? A. Tight junctions B. Synapses C. Dendrites D. More than one of the above

A. Tight junctions The blood-brain barrier is primarily composed of endothelial cells with tight junctions that prevent the movement of most solutes. Astrocytes also contribute to the function of the blood-brain barrier; however, these glial cells do not have dendrites or synapses, which are characteristic of neurons and their interconnections, respectively.

Which of the following amino acid residues is most likely to be found in the transmembrane domain of EGFR, a protein? A. Val B. Tyr C. Glu D. Lys

A. Val The membrane-spanning domain of EGFR is in contact with the nonpolar tails of the phospholipid molecules that comprise the bilayer membrane. This region would be expected to be abundant in nonpolar amino acid residues, such as Val (valine).

Cell differentiation is mediated primarily by: A. gene expression levels. B. differing genetic material. C. relative age of the cell. D. DNA ethylation.

A. gene expression levels. Cell differentiation occurs primarily through different gene expression levels.

A group of police officers is brought together to discuss what changes, if any, are needed in MHA policies. After the discussion, the group submits a plan outlining policies that entail more severe punishments and more permissive escalation-of-force regulations. This plan most likely developed as a result of: A. group polarization. B. negative reinforcement. C. gender discrimination. D. groupthink.

A. group polarization. Group polarization is a phenomenon in which a group comes to express a consensus view that is more extreme than the individual views of any one group member before the group discussion began. Here, the more extreme policy is likely the result of group polarization during the discussion. The others: D. groupthink. While groupthink can lead a group to take extreme stances out of a sense of invulnerability, the question doesn't directly describe factors of groupthink (illusion of invulnerability, self-censorship, stereotyping, etc.) that would make D the correct answer. It does directly describe the phenomenon of group polarization.

During strenuous exercise, lactic acid buildup in cells causes the creation of a hydronium complex known as the Eigen cation (H9O4+). If water molecules then experience hydrogen bond attractions to the Eigen cation, this attractive force: A. results in a semi-stable shell of water molecules around the hydronium. B. results in an inability of hydronium to be neutralized by bases the way normal H+ ions would be. C. results in the ability of muscle cells to reverse both the hydronium creation process and the lactic acid creation process once sufficient oxygen is once again made available. D. results in mobility of hydronium within the environment surpassing the mobility of regular water molecules.

A. results in a semi-stable shell of water molecules around the hydronium. A process known as "hydration" or "solvation" occurs when the attractive force of an ion molecule causes a thin shell of water molecules to surround it. In the case of hydronium (H3O+), each of the H atoms attracts the O atom in an H2O molecule due to hydrogen bonding. These H2O molecules cause a "shell" of water molecules to surround the hydronium.

The researchers interviewed one of the participants in the study, who, at 50 years of age, recently experienced her first year of poverty. When asked to explain her financial history, she credits her hard work and determination for her success despite being from a low-income neighborhood, and attributes her recent financial struggles to her employer's refusal to give her a raise. Her story is an example of: A. self-serving bias. B. fundamental attribution error. C. prejudice. D. ethnocentrism.

A. self-serving bias. Self-serving bias is the tendency to attribute good outcomes with internal factors (for example, hard work), and ascribe bad outcomes to external factors (boss not giving a raise).

It has been shown that pheromones induce the body to secrete sex hormones more readily. All of the following are expected effects of sex hormones EXCEPT: A. testosterone causes the Leydig cells in the seminiferous tubules to produce sperm. B. estrogen causes the endometrial lining to thicken. C. estrogen inhibits bone resorption. D. testosterone causes the development of secondary sex characteristics in boys.

A. testosterone causes the Leydig cells in the seminiferous tubules to produce sperm. Sperm is produced by the Sertoli cells of the seminiferous tubules, not the Leydig cells. Remember: Leydig cells produce testosterone, Sertoli cells do pretty much everything else.

What are the purines?

Adenine and Guanine (2 rings) *Pure As Gold*

What is the pH of a 0.10 M aqueous solution of aspirin? Note: We know from the passage that aspirin is relatively acidic with a PKa of 3.5 A. 1.0 B. 2.3 C. 11.7 D. 10.5

B. 2.3 Acetylsalicylic acid is a weak acid, with a pKa of 3.5. The pH can be determined from the equilibrium expression: Ka = [H+][A-]/[HA] 10-3.5 = x2/(0.1-x) Since x will be small, we can approximate 0.1 - x ≈ 0.1, giving: 10-3.5(0.1) = x2 10-4.5 = x2 10-2.25 = x Since x equals the hydrogen ion concentration, taking the -log(10-2.25) = pH = 2.25. Additionally, since we know aspirin is acidic from its given Pka value of 3.5, we can rule out C and D as those are PH values for basic compounds, and we can rule out A because that is a very low pH, which would likely only be that low when looking at a strong acid, which aspirin is not. Therefore, B has to be the correct answer.

How much heat is produced from the complete combustion of 30.0 g of methane, if the enthalpy of reaction is -890 kJ/mol? A. 1.7 x 103 J B. 1.7 x 106 J C. 4.7 x 106 J D. 4.7 x 109 J

B. 1.7 x 106 J First, note that methane has a molecular formula of CH4. Thus, its molecular weight is approximately 12 + 4(1) = 16 g/mol. For one mole, ΔH = -890 kJ, so now we must convert grams of methane to moles of methane and convert kJ to J. Using approximations, the calculation is: (30 g CH4) (1 mol/16 g) (-890 kJ/mol) = 1.8 x 103 kJ released (1.8 x 103 kJ) (103 J /1 kJ) = 1.8 x 106 J

A 60-kg runner raises her center of mass approximately 0.25 m with each step. Although her leg muscles act as a spring, recapturing the energy each time her feet touch down, there's an average 10% loss with each compression. What must the runner's additional power output be to account for only this loss, if she averages 0.8 s per stride? A. 0 W B. 19 W C. 32 W D. 46 W

B. 19 W This is a multi-step question, though each step is relatively straightforward. The gravitational potential energy at the runner's height is: PE = mgh PE =(60 kg)(10 m/s2)(0.25 m) = 150 J Most of this energy is conserved as the runner hits the ground and her muscles capture the energy as spring potential energy, so the question only asks about the lost energy, amounting to 10%, or 15 J. Don't worry about the mechanics of which foot lands first and how much of the kinetic energy each one absorbs. The question stem doesn't give that kind of information. An additional 15 J is needed per stride, and a stride occurs every 0.8 s. Thus: P =(15 J) / (0.8 s) ≅ 18 W The closest answer is B.

A scientist investigating Weber's law detects a just-noticeable difference for a subject when shifting from a 5 kg to an 8 kg mass. When repeating the trial, how many kilograms must be added to a 15 kg mass to replicate the effect? A. 6 kg B. 9 kg C. 18 kg D. 24 kg

B. 9 kg Weber's law states that the just-noticeable difference between two stimuli is directly proportional to the magnitude of the stimuli. If a 3 kg change creates a just-noticeable difference starting at 5 kg, tripling the initial mass will require triple the difference. Thus, the answer is 9 kg.

If 3000 molecules of triglycerides are hydrolyzed into their component molecules, what would the resulting mixture contain? A. 3000 fatty acid molecules and 3000 glycerol molecules B. 9000 fatty acid molecules and 3000 glycerol molecules C. 3000 phospholipid molecules and 3000 glycerol molecules D. 9000 phospholipid molecules and 3000 glycerol molecules

B. 9000 fatty acid molecules and 3000 glycerol molecules Triglycerides are composed of one glycerol molecule and three fatty acid molecules. So, if we start with 3000 triglyceride molecules, we would expect to have 9000 molecules of fatty acids and 3000 molecules of glycerol after hydrolysis.

Which of the following contradicts Weber's law? A. A weightlifter who doesn't notice a 5-pound difference in weight added in 1-pound increments, but who notices the difference in weight added in one 5-pound increment B. A nonlinear relationship between the intensity of a stimulus and an individual's ability to detect it C. The existence of a threshold, above which stimuli are detectable and below which stimuli are not detectable D. Hearing a whisper in a quiet room but not hearing a shout in a noisy room.

B. A nonlinear relationship between the intensity of a stimulus and an individual's ability to detect it Weber's law postulates that there is a linear relationship, not a nonlinear relationship, between the intensity of a stimulus and its detection.

What is the function of ligase during S-phase? A. Begins synthesis of a new strand of copied DNA B. Binds together pieces of the lagging strand C. Repairs pieces of mis-replicated DNA D. Opens the double helical strand of DNA to begin replication

B. Binds together pieces of the lagging strand This question is asking us to simply recall a fact about the S-phase of a cell, aka DNA replication. You should know that DNA ligase is the enzyme that connects Okazaki fragments on the lagging strand of DNA being replicated. An overview of some of the key structures and enzymes of DNA replication is shown below.

The presence of differences between this experiment and actual prison conditions represents a critique of which aspect of the study design? A. Construct validity B. External validity C. Researcher bias D. Reliability

B. External validity External validity refers to the extent to which we can generalize results onto different experimental settings or real life situations. Other: A. Construct validity Construct validity refers to whether or not measures actually assess the variables that they are intended to assess. For example, issues with how verbal abuse was defined in this study might pertain to construct validity.

Which of the following would likely decrease an individual's self-efficacy with regard to a particular task? A. Seeing a task performed successfully B. Feeling that past failures were due to other circumstances C. Being offered positive encouragement by others D. Learning stress-reduction techniques in regard to the task

B. Feeling that past failures were due to other circumstances This is an example of an external locus of control, which might increase an individual's self-esteem, but not self-efficacy. Self-efficacy tends to be associated with an internal locus of control, as it refers to an individual's belief in their own ability to perform a specific task or achieve a particular goal.

The results of a separate study of the thermodynamic parameters for the interactions of proteins with cyclohexanol and quaternary ammonium salts indicate that the hydrophobic solute-solute interaction is spontaneous, and that ΔH and ΔG have opposite signs. Which of the following must be true for this interaction when there is an increase in temperature? I. ΔH > ΔG II. 0 < ΔS III. ΔH < ΔS A. I only B. I and II only C. II and III only D. I, II, and III

B. I and II only For the interaction to be spontaneous, the free energy change of the reaction must be negative. The question states that the enthalpy and free energy changes for the interaction have opposite signs. Thus, ∆G is negative and ∆H is positive, so I is true. An increase in temperature means that there is an increase in the average kinetic energy of the system, so there is an increase in entropy and II is also correct.

Based on passage information, which of the following are post-transcriptional modifications likely involved in the IAV life cycle? I. Splicing II. Polyadenylation III. Glycosylation A. I only B. I and II only C. I and III only D. I, II, and III

B. I and II only Paragraph 2 states that splicing is part of the IAV life cycle, and also states that IAV uses host machinery for other post-transcriptional modifications (I). Since IAV genomic material is synthesized in the nucleus, this most likely includes polyadenylation, which is needed to export mRNA from the nucleus to the cytoplasm (II)

A principal of a high school seeks to establish rules and systems in the school that reflect a meritocracy. Which of the following goals must these systems achieve if the principal is to successfully establish a meritocracy? I. Outcome equality II. Skill equality III. Opportunity equality A. I only B. III only C. II and III only D. I and III only

B. III only A meritocracy is a society of people whose progress within the society is based on ability and talent rather than on class privilege or wealth. This requires that everyone be afforded the same opportunities to advance, yet only be rewarded based upon individual outcomes due to their individual talents and/or abilities, which can vary between persons (III).

Conn's syndrome, also known as primary hyperaldosteronism, is most likely to cause which symptom? A. High renin concentration B. Low blood potassium C. Low blood sodium D. Hypotension

B. Low blood potassium This question is asking you to recall the effects of aldosterone and how it achieves those effects. Aldosterone increases H2O and Na+ reabsorption from the kidney while exchanging K+ ions for Na+ ions. The triggers for and results of aldosterone secretion are shown below.

Which of the following statements regarding different types of neurons is most accurate? A. Sensory neurons and interneurons are both afferent neurons, while motor neurons are efferent neurons. B. Motor neurons are efferent neurons, sensory neurons are afferent neurons, and interneurons are neither. C. Motor neurons and interneurons are both efferent neurons, while sensory neurons are afferent. D. Motor neurons are afferent neurons, sensory neurons are efferent neurons, and interneurons are neither.

B. Motor neurons are efferent neurons, sensory neurons are afferent neurons, and interneurons are neither. This question is asking us to determine the accuracy of statements about different types of neurons. You should know that motor neurons carry signals outward, so they are efferent neurons. You should also know that sensory neurons carry signals inward, so they are afferent neurons. Interneurons are neurons that connect afferent and efferent neurons, so they fall into neither of the two categories.

In a follow-up study, the same participants were asked to persuade someone else to agree with the message from the original study. Researchers found that participants who viewed themselves as being good at persuading others performed best on this task. Which concept best describes this finding? A. Self-esteem B. Self-efficacy C. External locus of control D. Internal locus of control

B. Self-efficacy Self-efficacy refers to a person's sense of effectiveness or competence on a specific task. In this case, participants who viewed themselves as being competent at persuading others performed better on the experimental task, which reflects self-efficacy.

In a follow-up study, the emission spectra of both bound states of Y32 were shifted to longer wavelengths than the excitation spectra shown in Figure 2. What is the most likely cause of this shift? A. The emission intensity peak is usually lower than the excitation peak. B. There is a loss of vibrational energy when electrons move from the excited to the ground state. C. A fluorophore is typically excited at a wavelength at the peak of the excitation curve. D. Emission detection was selected at the peak of the emission curve.

B. There is a loss of vibrational energy when electrons move from the excited to the ground state. Longer-wavelength = lower-energy. If the energy required to excite electrons in the CPV fluorophore exceeds that which is emitted when the electrons relax, then energy other than the energy associated with emission must have been lost during the return to the ground state following excitation. Only choice B, which states that there is a loss of vibrational energy during the transition, provides a possible explanation consistent with this requirement

A follow-up study finds that first-generation immigrants between the ages of 25 and 34 are more likely than the participants in this study to experience poverty. However, second-generation immigrants aged 25-34 experience poverty at the same rate as the study participants. This finding would best serve as societal evidence of: A. intragenerational mobility. B. intergenerational mobility. C. social reproduction. D. meritocracy.

B. intergenerational mobility. Intergenerational mobility describes upward or downward movement in social class between two or more generations. In this example, the first-generation immigrants tended to be in a lower socioeconomic class than the study sample, whereas second-generation immigrants had achieved parity with the study sample, which would qualify as upward mobility. The other : A. intragenerational mobility. Intragenerational Intragenerational mobility describes changes in social class that occur within one lifetime. Since the change in social class occurred across generations, this is not an example of intragenerational mobility.

Efforts to treat lactic acid buildup in muscles were attempted using dissected muscle specimens in the laboratory. One of these experiments involved ammonium formation from dissolved ammonia. Under conditions of excessive lactic acid: A. the final concentration of ammonium will be higher than otherwise due to higher pH. B. the final concentration of ammonium will be higher than otherwise due to lower pH. C. the final concentration of ammonium will be lower than otherwise due to higher pH. D. the final concentration of ammonium will be lower than otherwise due to lower pH.

B. the final concentration of ammonium will be higher than otherwise due to lower pH. Under conditions of excessive lactic acid, the environment is more acidic, so the pH of the environment is lower and choices A and C can be eliminated. In an acidic environment, a base such as ammonia (NH3) will dissolve into its conjugate acid, ammonium (NH4+), to a greater extent than would have been the case in a neutral or a basic environment. An environment with lower pH is an environment that is more acidic.

Problems with language production and impairment of an individual's ability to produce language is likely due to _______ aphasia

Broca's

Phosphorous acid, a common ingredient used for potable water treatment, has a molecular formula of: A. H3PO5. B. H3PO4. C. H3PO3. D. H3PO2.

C) H3PO3. This has one fewer oxygen atom than phosphoric acid, so it is phosphorous acid. Others: A. H3PO5. This is perphosphoric acid. B. H3PO4. This is phosphoric acid. D. H3PO2. This is hypophosphorous acid.

Which of the following is NOT true about the amygdala? A. The amygdala is heavily involved in fear conditioning. B. There are two amygdalae, one in each hemisphere. C. The amygdala is located deep within the parietal lobe. D. The amygdala is considered part of the limbic system.

C)The amygdala is located deep within the parietal lobe. The amygdalae are located within the temporal lobes. There are two amygdalae per person normally, with one amygdala on each side of the brain.

The Omilteme Cottontail is a particularly large breed of rabbit with an average weight of 3 kg. If its leg muscles act as imperfectly elastic springs, how much energy is stored if the rabbit lands from a height of 0.5 m and its legs are compressed by 0.2 m? A. -0.6 J B. 0 J C. 13 J D. 14.7 J

C. 13 J The muscles are not perfectly elastic, so some energy is lost. The potential energy stored in the muscle at the peak of the rabbit's height is PE = (3 kg)(9.8 m/s2)(0.5 m) ≅ 15 J. Since some energy is lost, 13 J is a reasonable answer.

A hospital purchases brand-new GKS-Co and GKS-X machines. Five years after installation, what is the expected ratio of the total atomic mass of material in the Co machine to that in the X machine, assuming both machines start with the same mass of radioactive material? A. 16:1 B. 5:1 C. 1:1 D. 1:5

C. 1:1 When reading questions, be careful not to read too quickly. In this case, we may be led to assume that the question is asking about the percentage of a certain isotope that is left after radioactive decay. However, the question is asking about atomic mass. While β-decay does cause a nuclear transmutation of protons to neutrons (β-plus) or neutrons to protons (β-minus), the atomic mass lost when producing Ɣ-rays is essentially zero. This means that whether after one (Co) or five (X) half-lives, the atomic mass will be the same in both samples.

At STP, how many liters of carbon dioxide are produced by reacting 100 g of calcium carbonate with an excess of hydrochloric acid? A. 0.0 L B. 11.2 L C. 22.4 L D. 44.8 L

C. 22.4 L IMPORTANT: One mole of any gas at STP (standard temperature and pressure) ALWAYS has a volume of 22.4 L. Thus, the volume of gas produced will be 22.4 L at STP and the calculation isn't needed The balanced chemical equation is: CaCO3(s) + 2 HCl(aq) → CO2(g) + H2O(l) + CaCl2(aq) From the periodic table, the formula weight of calcium carbonate is 40 g/mol + 12 g/mol + 3(16) g/mol = 100 g/mol. 100 g of calcium carbonate therefore represents one mole. From the balanced chemical equation, this will produce one mole of carbon dioxide gas. 100 g CaCO3 x 1 mol/100 g x 1 mol CO2/1 mol CaCO3 x 22.4 L/mol = 22.4 L CO2

A balloon has a volume of 3.0 L at 25°C. What is the approximate volume of the balloon at 50°C assuming ideal behavior? A. 1.5 L B. 2.0 L C. 3.3 L D. 6.0 L

C. 3.3 L Here we assume that pressure is constant. Charles' law states that there is a direct relationship between the volume of an ideal gas and its temperature, when pressure and the number of moles is constant. As with all calculations involving the ideal gas law, the temperature must be in Kelvin. We can approximate the initial temperature as 300 K (273 K + 25) and the final temperature as 320 K (273 K + 50). The relationship then becomes this: V1/T1 = V2/T2 (3.0 L) / (300 K) = V2 / (320 K) [(3.0)(320)] / (300) = 320 x 10-2 = 3.2 L

If all of the subjects in this study participated on a voluntary basis, what type of organization would the study be? A. A mimetic organization B. A coercive organization C. A normative organization D. A utilitarian organization

C. A normative organization The three general types of organizations are coercive, normative, and utilitarian. Normative organizations are ones that people join due to some shared ethical or ideal goal. Because these subjects are volunteering for the study, they are participating in a normative organization. The others: A. A mimetic organization Mimetic organizations are ones that attempt to copy another organization. That doesn't apply to this situation. B. A coercive organization Coercive organizations are organizations in which members are forced to join. Prison is a classic example. D. A utilitarian organization Utilitarian organizations are organizations in which members are compensated for their involvement. Employees of a particular company share membership in a utilitarian organization.

For the reaction below, which solvent will best promote an SN2 mechanism of reaction? A. H2O B. Methanol C. Acetone D. Toluene

C. Acetone The SN2 mechanism is favored by polar aprotic solvents, such as acetone or DMSO. The structure of acetone is shown below; note that it has a dipole moment ("polar"), but does not contain O-H or N-H bonds ("aprotic").

A student assisting with the experiment would observe all of the following about the electron transport chain EXCEPT: A. Electrons are passed from carriers with lower reduction potential to those with higher reduction potential. B. Complex I is also a proton pump. C. All electron carriers are mobile and hydrophobic. D. The electron carriers can transport a maximum of 2 electrons.

C. All electron carriers are mobile and hydrophobic. Not quite. In the ETC, carriers travel inside the inner mitochondrial membrane, passing electrons from one to another and pumping protons across the inner mitochondrial membrane. Therefore, they are mobile. In order to travel inside the hydrophobic interior of the membrane, we would expect them to all be hydrophobic. However, cytochrome c is a highly water-soluble protein, unlike other cytochromes. Some extreme statements in the sciences are true, but most of the time things aren't all one way.

Devic's syndrome is a condition involving the demyelination of the optic nerve and the spinal cord. Which of the following neuronal effects is NOT a direct result of Devic's syndrome? A. Decreased protection of the neuron B. Decreased speed of impulse propagation C. Decreased strength of the action potential D. Decreased electrical insulation

C. Decreased strength of the action potential This question is asking us to remember the function of myelin sheaths. Even without remembering all the details, we know that choice C must be the false statement (and, therefore, the right answer) because electrochemical signals in neurons are all-or-nothing. The diagram below depicts the myelin sheath along with associated structures, including an oligodendrocyte, which is the myelin-producing cell in the central nervous system. Note also the nodes of Ranvier, or gaps between segments of myelin sheath through which ions can travel in and out of the cell during the stages of the action potential.

In an adult, which of the following cell types is LEAST likely to enter a programmed G0 phase of the cell cycle? A. Liver cells B. Kidney cells C. Epithelial cells D. Neurons

C. Epithelial cells For this question, we need to know what the G0 phase (shown below along with the rest of the cell cycle) entails. This is the state that a cell will enter if it does not need to divide. Epithelial cells comprise the skin and the linings of the organs, so they undergo rapid cell divisions in order to replace the damaged cells. D. Neurons Neurons in adults do not divide and are almost always found in G0

Based on the results of the study, individuals who assume that abuses in institutions are done by those with dispositional propensities to violence have likely committed what type of error? A. Confirmation bias B. Availability heuristic C. Fundamental attribution error D. Expectation bias

C. Fundamental attribution error This experiment showed that anyone can act in the way the participants did in the right conditions, not because of certain personality characteristics. To assume otherwise is to commit the fundamental attribution error, which posits that we are more likely to attribute others' behavior to dispositional, rather than situational, factors.

Which psychometric properties are best supported if the experiences of the low-income students in the study are similar to those of other low-income students around the country? I. External validity II. Generalizability III. Internal consistency A. I only B. III only C. I and II only D. I, II, and III

C. I and II only External validity describes the generalizability of the study, or the extent to which results can be applied to a wider population (I and II). The other: D. I, II, and III Internal consistency refers to how well the items of a test that assess a certain construct of interest correlate with each other. It is not directly relevant for whether findings can be generalized to a different population (III).

Underproduction of pulmonary surfactant in IRDS leads to decreased compliance of alveolar tissue. Based upon this information, which of the following must be true regarding pulmonary surfactant? A. Its adsorption to the water-alveolar interface increases surface tension, preventing alveolar collapse due to intra-thoracic pressure. B. Its absence decreases the minimum radial size of alveoli able to avoid collapse at a given pressure of inspired air. C. Its adsorption to the water-alveolar interface decreases surface tension, decreasing the pressure difference required to inflate the airway. D. Its presence increases the efficiency of gas exchange across the alveolar membrane by decreasing the surface area of the alveolus at a given pressure of inspired air.

C. Its adsorption to the water-alveolar interface decreases surface tension, decreasing the pressure difference required to inflate the airway. Pulmonary surfactant adsorbed to the air-water-alveoli interface reduces surface tension and the total force resisting expansion. This increases pulmonary compliance—a measure of lung volume change at a given pressure of inspired air—and decreases the work required to expand the lungs at a given atmospheric pressure.

A person who experiences a prolonged deficiency of thiamine due to excessive drinking may develop which of the following neurological disorders? A. Down syndrome B. Alzheimer's disease C. Korsakoff's syndrome D. Schizophrenia

C. Korsakoff's syndrome Korsakoff's syndrome is a neurological disorder that is most often seen in people who have severe prolonged alcoholism, which often leads to severe thiamine deficiency.

Which of the following locations is expected to have the highest number of glucagon receptors? A. Stomach B. Heart C. Liver D. Skeletal muscle

C. Liver This question is asking you to recall the function of glucagon and where it is likely to induce this function. Glucagon is released by the pancreas as a response to low blood glucose levels. Its main purpose is to increase glycogenolysis to increase blood glucose. Glycogen is stored in the liver; therefore, most of glucagon's action occurs in the liver.

Which of the following would be LEAST useful in cellular movement? A. Flagella B. Actin polymerization C. Microtubule depolymerization D. Cilia

C. Microtubule depolymerization In order for cells to travel to the site of injury, they need to migrate. Microtubule depolymerization is responsible for separating chromosomes during anaphase of mitosis or meiosis I or II. It does not contribute to overall cell migration.

If a scientist chooses not to employ an SEC column, but wishes to fractionate a protein sample on the basis of only molecular weight, what technique would be most appropriate? A. Affinity chromatography B. Ion-exchange chromatography C. SDS-PAGE D. NMR spectroscopy

C. SDS-PAGE SDS-PAGE is an electrophoretic technique that involves the binding of the anionic detergent SDS to a polypeptide chain. SDS binding denatures and imparts an even distribution of charge per unit mass to the protein, resulting in fractionation by approximate size alone during electrophoresis. The others: A. Affinity chromatography Affinity chromatography is used to separate molecules, including proteins, based upon their specific interaction with the stationary phase. During protein purification, this is often an antigen-antibody, receptor-ligand, or enzyme-substrate interaction. B. Ion-exchange chromatography Ion-exchange chromatography separates charged particles based on their affinity for charged elements of the ion exchange column.

Researchers are planning to conduct a study, using a broader sample of American college students, to explore cultural differences in the expression of emotion by assessing participants' facial expressions. What result are researchers likely to NOT observe? A. Some cultures display more happiness than others. B. Some participants showed almost no facial expressions. C. Some cultures display fear and happiness differently from others. D. All participants in the study displayed sadness in the same way.

C. Some cultures display fear and happiness differently from others. Since fear and happiness are part of universal emotions, it would be expected for different cultures to show them using the same facial expressions. As such, it is very unlikely that the researchers would have seen different facial expressions for these emotions. The others: D. All participants in the study displayed sadness in the same way. Since sadness is a universal emotion, it would be expected for different cultures to display it using the same facial expression.

Figure 1 shows a drop in the first ionization energy as a function of the valence, or outermost, electrons from beryllium to boron. Which of the following best explains the source of this drop? Note: beryllium is in the 2s2 orbital and transition to boron brings it to the 2p orbital A. Boron contains one valence electron, while beryllium contains none. B. After adding two electrons to the valence s subshell in beryllium, the third valence electron in boron must enter an orbital that already contains an electron. C. The two valence electrons in beryllium occupy a region of space that is more compact than that of boron. D. Elements can have a variable number of electrons.

C. The two valence electrons in beryllium occupy a region of space that is more compact than that of boron. Electrons in orbitals that are more spatially compact are held more tightly to the positively charged nucleus. Therefore, the ionization energy is predicted to be higher, which it is.

Viruses are directly involved in which of the following processes in bacteria? A. Transformation B. Conjugation C. Transduction D. Binary fission

C. Transduction Transduction is a form of horizontal gene transfer in bacteria in which bacteriophages (viruses that infect bacteria) transmit genomic material. the others: A. Transformation Transformation involves direct uptake of genetic material from the environment and is not mediated by viruses. B. Conjugation Conjugation is a horizontal gene transfer process in bacteria in which plasmid DNA is transferred from one bacterium to another through a pilus. Viruses are not involved. D. Binary fission Binary fission is how bacteria reproduce asexually.

In order for an enzyme obeying the Michaelis-Menten model to reach 1/2 of its maximum velocity: A. [S] must be equal to 2 Km. B. [S] must be equal to 1/2 Km. C. [S] must be equal to 1 Km. D. [S] must be equal to 10 Km.

C. [S] must be equal to 1 Km. [S] is the concentration of the substrate, and Km implies that half of the active sites on the enzymes are filled. Different enzymes have different Km values. When all of the active sites are occupied, a reaction has reached maximum velocity. Therefore, Km is equal to the concentration of the substrate when the rate is half of the maximum velocity.

The polymorphism located at the 677th location involves the replacement of: Note: The passage states that cytosine is replaced by thymine at the 677th position of the MTHFR gene, A. 2-ring structure to a single-ring structure. B. single-ring structure to a 2-ring structure. C. a single-ring structure with a single-ring structure. D. a 2-ring structure with a 2-ring structure.

C. a single-ring structure with a single-ring structure. It is stated in the first paragraph that the polymorphism involves the conversion of a cytosine to a thymine. For the MCAT, you should know that adenine and guanine are purines (2-ring structures) and that thymine, cytosine, and uracil are pyrimidines (single-ring structures). As such, this is a conversion from a pyrimidine (single-ring structure) to another pyrimidine (single-ring structure).

In comparison to a neural cell, a gastrointestinal cell would likely spend: A. less time in S phase. B. less time in M phase. C. less time in G0. D. the same amount of time in all cell cycle phases.

C. less time in G0. G0 is a non-growing state that accounts for the observed differences in length in the cell cycle. While intestinal cells will divide twice per day, neuronal cells do not divide following initial differentiation and therefore remain permanently in G0. The diagram below depicts the stages of the cell cycle, including G0.

Which of the following electronic transitions for hydrogen would result in the emission of a quantized amount of energy? A. n = 1 → n = 2 B. n = 2 → n = 3 C. n = 5 → n = 4 D. n = 4 → n = 6

C. n = 5 → n = 4 In order to emit a photon, an electron must move from a higher energy level to a lower energy level. Only choice C shows such a transition.

Y32 is pH-sensitive. This can be a problem when employing it to monitor changes in the energy balance of a cell over time because: A. pH can differ between cells. B. the ATP-to-ADP ratio of a cell depends on pH. C. pH may change over time in the same cell. D. decreased pH favors the CPV B-state.

C. pH may change over time in the same cell. If the biosensor is pH-sensitive, then changes in cellular pH over the course of a measurement could interfere with changes in the energy balance of the cell, as reflected by the cell's ATP-to-ADP ratio.

The passage of IgG antibodies from mother to fetus illustrates: A. natural immunity B. cell-mediated immunity. C. passive immunity. D. nonspecific immunity.

C. passive immunity. Passive immunity is the transfer of active humoral immunity in the form of ready-made antibodies, from one individual to another. The others: A. natural immunity. Natural immunity is immunity that is present in the individual at birth, prior to exposure to a pathogen or antigen, and that includes intact skin, salivary enzymes, neutrophils, natural killer cells, and complement. B. cell-mediated immunity. Cell-mediated immunity is an immune response that does not involve antibodies, but rather involves the activation of phagocytes, antigen-specific cytotoxic T-lymphocytes, and the release of various cytokines in response to an antigen. D. nonspecific immunity. The innate (non-specific) immune system includes anatomical barriers, secretory molecules, and cellular components. Among the mechanical anatomical barriers are the skin and internal epithelial layers, the movement of the intestines, and the oscillation of bronchopulmonary cilia.

A horizontal gene transfer process in bacteria in which plasmid DNA is transferred from one bacterium to another through a pilus is known as _________

Conjugation

What is the net charge on a phenylalanine molecule at pH 1? A. -1 B. 0 C. +0.5 D. +1

D. +1 Deprotonation of the carboxylic acid functional group common to all amino acids occurs at approximately pH = 2.5. Below this pH amino acids are fully protonated. Phenylalanine is a neutral amino acid, so in its fully protonated form at pH =1 it has a net charge of +1 The image below depicts phenylalanine at this pH.

What is the exclusion limit of the SEC column used to create the calibration curve shown in Figure 2? (note: 1 Dalton ≈ 1 g/mol) Note: Figure 2 indicates that the exclusion limit of the SEC column is log (MW) = 6. A. 10 kDa B. 100 kDa C. 600 kDa D. 1000 kDa

D. 1000 kDa Figure 2 indicates that the exclusion limit of the SEC column is at log (MW) = 6. The molecular weight can be found by taking the antilog of 6, 106 D = 1000 kD.

Which of the following alkyl chlorides is most likely to undergo an SN1 reaction? A. Chloromethane B. Chloroethane C. 2-chloropropane D. 2-chloro-2-methylpropane

D. 2-chloro-2-methylpropane This compound is also called tert-butyl chloride. An SN1 reaction proceeds by way of a mechanism in which the leaving group (in this case, a chloride) dissociates in a kinetically slow step producing a planar carbocation, which is then rapidly attacked by a nucleophile. The reactivity of an SN1 mechanism decreases as 3o > 2o > 1o. Dissociation of chloride produces a tertiary carbocation, and there are three electron donating groups that stabilize it, so D is the best choice.

An artificial leg designed for use by runners is spring-based in order to mimic the compression required of a muscle during hard running. For safety reasons, it was determined that the leg should be able to absorb as much as 125 J of kinetic energy without compressing more than 10 cm, or the runner would be likely to stumble. Neglecting energy lost as heat, what should the spring constant be? A. 250 N/m B. 2,500 N/m C. 12,500 N/m D. 25,000 N/m

D. 25,000 N/m When the leg "absorbs" kinetic energy, it is converted to elastic potential energy. We are assuming a perfectly elastic process. Thus, the leg needs to support up to 125 J of elastic PE. The formula for potential energy contained in a spring is PE = ½kx2. Since PE and KE are interconverted as the individual runs, we can write this formula as KE = ½kx2, which can be rearranged to k = (2KE)/x2. k = (2)(125 J) / (0.10 m)2 k = (250 J) / (.01 m2) k = 25,000 N/m

A person pushes horizontally on a 50-kg crate, causing it to accelerate from rest and slide across the surface. If the push causes the crate to accelerate at 2.0 m/s2, what is the velocity of the crate after the person has pushed the crate a distance of 6 meters assuming there is no friction? A. 1.2 m/s B. 2.7 m/s C. 3.4 m/s D. 4.9 m/s

D. 4.9 m/s Since the crate is initially at rest, Vi = 0 m/s, the acceleration a = 2.0 m/s2, and the displacement = 6 m. The appropriate kinematic equation is vf2 = vi2 + 2ad. Substituting the variables gives: vf2 = (0 m/s)2 + 2(2 m/s2)(6 m) vf2 = 24 m2/s2 vf = ~5 m/s

Which of the following particles is expected to have the LEAST mass? A. An alpha particle B. A beta particle C. A positron D. A gamma particle

D. A gamma particle A gamma particle is a photon of electromagnetic energy, which has essentially no mass. Other choices: A. An alpha particle An alpha particle is a He nucleus. It consists of two protons and two neutrons, and has a mass of 4 amu. B.A beta particle A beta particle is the nuclear equivalent of an electron, which has a mass of approximately 1/1800 of a proton. C. A positron A positron is the antiparticle of an electron and also has a mass of approximately 1/1800 of a proton.

Which person in a Gamer's life is most likely be a member of the Gamer's secondary group? A. A teammate B. A parent C. A gaming champion D. An opponent

D. An opponent Secondary group members interact superficially, and their relationships tend to not last very long. Others: A. A teammate This is a member of a primary group, which features direct interactions that last a significant period of time. B. A parent This is a member of a primary group, which features direct interactions that last a significant period of time. C. A gaming champion This is a member of a reference group, against which professional Gamers would evaluate themselves. It is possible that the Gamer in question has interacted with a gaming champion, but there is no evidence in the question that categorizes the gaming champion as belonging to either the primary or secondary group.

In what way does the synthesis of phage proteins in an infected bacterium differ from protein synthesis in a eukaryotic cell? A. Eukaryotic protein synthesis begins prior to completion of transcription. B. Eukaryotic protein synthesis occurs in the cytoplasm. C. Synthesis of prokaryotic proteins occurs only from mRNA molecules coding for a single protein. D. Eukaryotic protein synthesis takes place on 80S ribosomes.

D. Eukaryotic protein synthesis takes place on 80S ribosomes. Eukaryotic protein synthesis occurs on 80S ribosomes. These are distinct in their subunit composition from 70S ribosomes, which are found exclusively in prokaryotes. "Phage" is short for "bacteriophage," meaning a virus that reproduces using the host prokaryotic machinery

An individual with Wernicke's aphasia would most likely have difficulty with what aspect of communication? A. Producing sound B. Constructing words C. Forming sentences D. Expressing meaning

D. Expressing meaning People with Wernicke's aphasia have difficulty connecting meaning to language. Wernicke's area is thought to be involved in language comprehension; thus, impairments to this area may impair an individual's ability to understand language or express meaning.

Based on the concept of the looking-glass self, which reaction is most likely for a male Seattle welfare recipient who has a mental illness? A. He will redirect feelings of bias towards police during potential MHA incidents. B. He will seek out other welfare recipients. C. He will seek out other welfare recipients with mental illness. D. He will internalize perceived police bias.

D. He will internalize perceived police bias. The looking-glass self is a social psychological concept stating that a person's self grows out of society's interpersonal interactions and the perceptions of others. The term refers to people shaping their self-concepts based on their understanding of how others perceive them. If the man feels bias from society and/or police (as mentioned in paragraph 1), the looking-glass self theory states that he will internalize the bias/stigmatization directed towards him.

If a flat Petri dish containing a single layer of cells suspended in a viscous culture medium is tapped, some cells will collide into each other. If cell 1 collides into cell 2 on such a plate, which of the following describes what happens to cell 2 after the collision, assuming that it undergoes an elastic collision and experiences drag from the medium? I. Cell 2 moves with decreasing speed. II. Cell 2 moves with constant speed. III. Cell 2 decelerates until it reaches a velocity of 0 m/s. A. I only B. II only C. III only D. I and III only

D. I and III only Since the cells experience drag from the viscous medium, cell 2 will decelerate after the collision until it comes to rest, so statement III is correct. This also implies that cell 2's speed is decreasing until it comes to rest, making statement I correct and statement II incorrect.

Which region(s) of Figure 1 is/are likely to be affected by the movement of sodium ions into a cardiac neuron? I. P II. Q III. R A. I only B. I and II only C. II and III only D. I, II, and III

D. I, II, and III As stated in the passage, the P wave is associated with the depolarization and contraction of the atria. A rest potential is created when sodium ions are pumped to the outside surface of the membrane of a cell. When ion channels open, the sodium ions spontaneously flow back into the cell, resulting in depolarization and an action potential. Thus, I is correct. The passage also states that the Q and R waves are associated with the contraction of the ventricles. Like atrial contraction, ventricular contractions result from depolarization, which would involve the inward movement of cations like sodium ions. Thus, II and III are also correct.

A patient who begins to take a parasympathetic agent is most likely to exhibit what new symptom? A. Increased blood pressure B. Increased heart rate C. Dilated bronchioles D. Increased salivation

D. Increased salivation This question is asking us to recall the effects of stimulation of the parasympathetic nervous system, which is responsible for "rest-and-digest" responses. The parasympathetic nervous system increases activity in the digestive tract to digest food, thus evoking increased salivation.

Which of the following is NOT an example of a strategy people use in impression management? A. Complimenting coworkers on their clothing B. Bragging about one's financial success while on a date C. Matching the behavior of a boss D. Revealing a friend's personal information while on a date Show Explanation

D. Revealing a friend's personal information while on a date Impression management involves the control of information about oneself and is characterized by techniques such as flattery, boasting, self-promotion, conformity, and ingratiation. In contrast, in this choice, an individual is attempting to control information about someone else.

Which of the following best explains the relationship between the danger cue and a fear response? A. The danger cue activates the parasympathetic nervous system, resulting in the fight-or-flight response. B. The danger cue activates the hippocampus, eliciting a fear response. C. The danger cue activates the sympathetic nervous system, causing the release of thyroid hormone, which causes a fear response. D. The danger cue activates the amygdala, which regulates a fear response.

D. The danger cue activates the amygdala, which regulates a fear response. The amygdala is the region of the brain that is responsible for regulating our perceptions of and reactions to aggression and fear. This is the region of the brain that would be activated by the danger cue and would trigger a fear response.

What would be a possible ratio level measure of religiosity? A. Whether or not a person believes in God B. The type of religion with which a person identifies C. The strength of a person's belief in an afterlife, on a scale from 1 (Low) to 5 (High) D. The number of times a person has been to church in the last month

D. The number of times a person has been to church in the last month A ratio level of measurement is one in which there are a range of quantitative responses, ordered at equally-spaced intervals, and with it being possible to score 0 (complete absence of the quantity).

The true weight of the p53 protein, as calculated by summing the weight of the amino acids encoded by its gene, is 43.7 kDa. Which of the following possible mechanisms would best explain this discrepancy from its estimated weight, as mentioned in the passage? A. The protein migrated a greater distance because it contains many positively charged residues. B. The protein migrated a smaller distance because it contains many negatively charged residues. C. The protein migrated a greater distance because it contains many negatively charged residues. D. The protein migrated a smaller distance because it contains many positively charged residues.

D. The protein migrated a smaller distance because it contains many positively charged residues. The final paragraph of the passage mentions that p53 is so named for its estimated molecular weight using SDS-PAGE. This question is asking us to determine a plausible reason for the 9.3 kDa discrepancy. SDS-PAGE is used to grant a uniform negative charge to all proteins in an assay. However, if the protein has enough charged residues on its own, or if insufficient SDS is used, it can cause the estimation to be less accurate. If there are enough positive charges, the negative charge of the protein will not be as great as anticipated and the molecule will travel a smaller distance, which, to the individual running the assay, usually means the mass of the protein is greater and would lead to the discrepancy described.

Which of the following types of proteins would be most efficiently fractionated by an SEC column? A. Two proteins with very high molecular weights B. Two proteins with similar molecular weights C. Two proteins with very low molecular weights D. Two proteins with substantially different molecular weights

D. Two proteins with substantially different molecular weights If SEC separates on the basis of differences in molecular weight, the resolution should increase if the molecular weights of the proteins differ by a large amount.

More complete fractionation of proteins using an SEC column could be achieved by using a: A. nonpolar solvent. B. vacuum across the column. C. larger protein sample concentration. D. longer column.

D. longer column. As with other forms of chromatography, increasing the column length will enhance the resolution of the column, leading to more completion fractionation by SEC. This is because the matrix material provides the physical means of separating the proteins. If the proteins come in contact with a longer length of matrix, the differences in retention forces experienced by the proteins will have a greater cumulative influence on the migration of the proteins, improving the differences in their retention times. Why its not B: B. vacuum across the column. Applying a vacuum will increase the flow rate through the column. Increasing the flow rate will only increase the rate at which eluent is collected; it will not improve separation.

Which of the following electronic transitions for a hydrogen atom would result in the emission of a photon that would be visible to the human eye, which corresponds to a wavelength of 400 - 700 nm? A. n = 1 to n = 3 B. n = 2 to n = 4 C. n = 2 to n = 1 D. n = 4 to n = 2

D. n = 4 to n = 2 The wavelength of light emitted during a particular electronic transition is determined by the energy difference (∆E) between the initial and final energy levels. The energy of each level can be determined using Equation 1 and the appropriate energy level. For light to be emitted, an electron must move from a higher to a lower level, a process that releases energy. Using Equation 1 and approximating the Rydberg constant as 1 x 107 m-1, the energy of the n = 4 level is: E4 = -1 x 107 m-1 / 42 = -1/16 x 107 m-1 E2 was calculated in choice C. ∆E = E2 - E4 = (-4/16 x 107 m-1) - (-1/16 x 107 m-1) = -3/16 x 107 m-1 A negative value means energy is released. To make the fraction easier to work with, round 3/16 to 3/15, or 1/5. We must convert to nanometers, and we can ignore the sign because it only shows whether energy is absorbed or released. 1 / (1/5 x 107 m-1) = 5 x 10-7 m

A correlation coefficient of 0 between a memory task and memory test performance means that there is: A. a strong negative relationship between the two variables. B. a strong positive relationship between the two variables. C. a perfect positive relationship between the two variables. D. no relationship between the two variables.

D. no relationship between the two variables. The correlation coefficient ranges from -1 to 1. A value of 1 implies that a linear equation describes the relationship between X and Y perfectly, with all data points lying on a line for which Y increases as X increases; this is also known as a perfect positive correlation. A value of -1 implies that all data points lie on a line for which Y decreases as X increases; this is also known as a perfect negative correlation. A value of 0 implies that there is no linear correlation between the variables.

Free radicals from ionizing radiation are highly unstable and have carcinogenic effects. These effects most likely result from damage to: A. proteins. B. phospholipids. C. the Golgi apparatus. D. nucleic acids.

D. nucleic acids. The question stem states that free radicals can cause cancer, which is a result of poorly regulated cell growth and division. Cancer is generally a product of mutations in DNA that disrupt these processes. Therefore, we must choose the answer that targets DNA.

Mobility that describes changes in social class that occur between two or more generations is called _________ mobility

IntERgenerational mobility

Would moving from n = 4 to n = 2 absorb or emit energy?

Moving from a higher energy to a lower energy emits energy of energy, therefore moving from n = 4 to n = 2 would emit energy, usually as a photon of light. The actual color of the n = 4 to n = 2 transition of hydrogen is teal (blue-green), with a wavelength of 486 nm.

Would moving from n = 2 to n = 4 absorb or emit energy?

Moving from a lower energy to a higher energy requires the absorption of energy, therefore moving from n = 2 to n = 4 would absorb energy, usually as a photon of light

organizations that people join due to some shared ethical or ideal goal are known as __________ organizations. Someone that volunteers for a cause they believe in is a part of this organization.

Normative

Periods vs Groups on periodic table

Periods are vertical and go down Groups are horizontal and move from left to right.

A gene transfer process in which genetic material is uptaken directly from the environment

Transformation

Problems with language comprehension and impairment of an individual's ability to understand language or express meaning is likely due to _______ aphasia

Wernicke's

organizations in which members are forced to join are known as _________ organizations Prison is an example of this type of organization

coercive

What are pyrimidines?

cytosine and thymine and uracil in RNA (one ring)

Mobility that describes changes in social class that occur within one lifetime is called _________ mobility

intRAgenerational mobility

If Keq is greater than 1

products are favored delta G is negative

if Keq is less than 1

reactants are favored and delta G is positive

organizations in which members are compensated for their involvement are known as ______ organizations. Employees of a particular company share membership in this organization.

utilitarian