AAMC Exam 4 FL Review

irreversible inhibition

active site is made unavailable for prolonged period of time or enzyme is permanently altered

Linkage

occurs when genes tend to be inherited together.

large ribosomal subunit of eukaryotic cells is

60S

intact prokaryotic ribosomes is

70s

Intact eukaryotic ribosome is

80s

Recombination

A combining of genes or characters different from what they were in the parents, occurs when genetic material is broken and recombined.

Imine

A double bond between a carbon and a nitrogen

innate immunity

A form of defense common to all animals that is active immediately upon exposure to pathogens and that is the same whether or not the pathogen has been encountered previously.

Look over, Suppose a defibrillator successfully returns a baby's heart to normal beating. Suppose further that 20 g of blood enters the heart at 25 cm/s and leaves 0.10 s later at 35 cm/s. What is the estimated average force on the 20 g of blood as it moves through the baby's heart? A. 0.020 N B. 0.20 N C. 20 N D. 2000 N

A. 0.020 N, average force is equal to the mass of blood multiplied by the average acceleration of the blood. The average acceleration is (35 cm/s - 25 cm/s)/0.10 s = 100 cm/s2 = 1 m/s2. The average force is 20 g × 1 m/s2 = 0.020 kg × 1 m/s2 = 0.020 N

Two vectors of magnitudes |A| = 8 units and |B| = 5 units make an angle that can vary from 0° to 180°. The magnitude of the resultant vector A + B CANNOT have the value of: A. 2 units. B. 5 units. C. 8 units. D. 12 units.

A. 2 units, The magnitude of A + B is as small as 3 units (when A and B are anti-parallel and make an angle of 180°) and as large as 13 units (when A and B are parallel and make an angle of 0°). The magnitude of 2 units is smaller than the smallest possible magnitude of vector A + B.

WAS iffy: What is the magnitude of the electric field in the electrical discharge produced in the excimer laser tube? A. 2.0 × 106 V/m B. 4.0 × 105 V/m C. 6.0 × 104 V/m D. 8.0 × 103 V/m

A. 2.0 × 106 V/m, 8.0 kV across 4.0 mm is 8000 V/0.004 m = 2.0 × 106 V/m.

If all of Gas X (from Step 6) is held in a sealed chamber at STP, what will be its approximate volume? A. 22.4 L B. 44.8 L C. 67.2 L D. 89.6 L

A. 22.4 L, The quantity of Gas X was given as 1 mole. One mole of gas occupies 22.4 L at STP.

Erythromycin interferes with protein synthesis by binding to which ribosomal subunit? A. 50S B. 60S C. 70S D. 80S

A. 50S, erythromycin inhibits bacterial protein synthesis by binding to the 23S rRNA component of the large subunit of the bacterial ribosome. The large subunit of the bacterial ribosome has a sedimentation coefficient of 50 Svedberg (S)

According to Spencer's views, if a wealthy person gives money to the poor, which outcome is to be expected for the giver? A. A heightened sense of virtue B. A heightened sense of social responsibility C. A reduced sense of social responsibility D. A reduced sense of guilt

A. A heightened sense of virtue, "Individual charity might refine the character of the donor...." (paragraph 6). The reference to a "refined," or improved character, suggests a "heightened sense of virtue" might accrue to the wealthy person who gives money to the poor.

Compared to treatment with Compound 2 alone, which cell line shows the greatest enhancement of chemotherapeutic activity as a result of sensitization by Compound 1? A. Acute leukemia B. Fibrosarcoma C. Cervical carcinoma D. Noncancerous fibroblast

A. Acute leukemia, The ratio of the values of CC95 to CC95 Combination, gives the "fold enhancement" that is produced by using a combination of compounds 1 and 2 instead of just Compound 2 alone. Acute leukemia cells show a 74-fold enhancement in apoptotic activity by using the combination of compounds 1 and 2, while the other cancer cell lines show only a roughly 10-fold enhancement.

Which procedure would be the best negative control for endogenous GABA-receptor function in frog oocytes? A. Addition of GABA to mock-transfected frog oocytes B. Transfection of wild-type GABA receptor into insect oocytes C. Addition of excess GABA to Rdl-transfected oocytes D. Transfection of wild-type GABA receptor into Rdl-expressing oocytes

A. Addition of GABA to mock-transfected frog oocytes, Transfection of GABA to mock-transfected frog oocytes would be the best negative control for endogenous GABA-receptor function. This procedure would ensure that the process of transfection per se does not generate a response to GABA.

iffy Based on the information in the passage, which description of an enzyme-substrate covalent intermediate is most likely correct? The substrate is covalently attached to: A. Asp14 through the phosphorus atom of the phosphate group. B. Asp14 through the oxygen atom of the phosphate group. C. Asp16 through the phosphorus atom of the phosphate group. D. Asp16 through the oxygen atom of the phosphate group.

A. Asp14 through the phosphorus atom of the phosphate group., covalent intermediate will occur through the nucleophilic substitution by the side chain carboxyl of Asp14 at the electrophilic phosphorus atom in the substrate, displacing a leaving group.

Which experiment can be used to investigate the transcriptional regulation of the Cdkn1a protein? A. Assessing Cdkn1a mRNA levels by RT-PCR B. Assessing Cdkn1a mRNA levels by Southern blotting C. Assessing Cdkn1a protein levels by quantitative PCR D. Assessing Cdkn1a protein levels by Western blotting

A. Assessing Cdkn1a mRNA levels by RT-PCR, it is logical to assess the mRNA levels as opposed to protein levels. RT-PCR is a molecular technique that measures mRNA levels of specific protein

wrong, Which saturated fatty acid is the most soluble in water? A. CH3(CH2)10COOH B. CH3(CH2)12COOH C. CH3(CH2)14COOH D. CH3(CH2)16COOH

A. CH3(CH2)10COOH, fatty acid that is the most soluble in water will have the shortest alkyl chain

Which conclusion can be drawn from the experimental results described in the passage? A. Compound 1 selectively sensitizes cancer cells to chemotherapeutic action by Compound 2. B. Compound 1 sensitizes all cells to chemotherapeutic action. C. Compound 2 induces apoptosis in cancer cells only in conjunction with treatment with Compound 1. D. Compound 2 inhibits the NF-κB signaling pathway, which leads to apoptosis.

A. Compound 1 selectively sensitizes cancer cells to chemotherapeutic action by Compound 2.

During phosphorylation of STAT5b proteins, phosphate groups are exchanged for what atoms on tyrosine residues? A. Hydrogen atoms of hydroxyl groups B. Hydrogen atoms of methyl groups C. Oxygen atoms of hydroxyl groups D. Carbon atoms of methyl groups Solution

A. Hydrogen atoms of hydroxyl groups, JAK2 is a tyrosine kinase. Tyrosine has a nucleophilic hydroxyl group that attacks the terminal phosphate group (γ-PO32-) on ATP, resulting in the exchange of the hydrogen atom of a hydroxyl group for a phosphate group of ATP.​

Passage context implies that Spencer's strong following in the United States during the nineteenth century was attributable, in part, to the country's: relatively substantial number of affluent residents. relatively strong sense of social responsibility. relatively strong grounding in Darwinist theories. A. I only B. III only C. I and II only D. II and III only

A. I only, "Nowhere did Spencer have a larger following than in the U.S., where his works were celebrated as powerful justifications for laissez-faire capitalism" (first paragraph). The author, then, implicitly attributes Spencer's popularity in the U.S. to his support for capitalism, and it follows that those who were prospering under this system would be the ones who found this support most attractive.

Which of the following best describes the author's attitude toward the subject of the passage? A. Intrigue B. Disbelief C. Confusion D. Approval

A. Intrigue, the author explains that contemporary research has begun to debunk earlier and more limited portrayals of the capacities of the Neandertals, the author presents the work of several scholars whose research testifies to the achievements of the Neandertals.

Which experiment would best link the result of experiments 1 and 2 to show that S. pneumoniae can cause apoptosis of host cells by contributing to DSBs? A. Measure levels of H2O2 produced by each strain. B. Determine if other factors are secreted by each strain. C. Determine if H2O2 is produced by other S. pneumoniae strains. D. Measure the number of DSBs that occur in AECs cultured with each strain.

A. Measure levels of H2O2 produced by each strain., Experiment 1 suggests that secreted factors from S. pneumoniae strains cause DSBs. Experiment 2 suggests that exposure to H2O2 induces apoptosis. An experiment that links the results obtained from these two independent experiments would be to confirm that the S. pneumoniae strains produce H2O2

When GABA is added to frog oocytes expressing either wild-type or Rdl GABA receptors, how does the membrane potential change? A. Oocytes become hyperpolarized as chloride ions enter them. B. Oocytes become depolarized and produce an action potential from sodium ion entry. C. Oocytes become hyperpolarized as chloride ions exit them. D. No change occurs in potential; chloride ions enter and sodium ions exit the oocytes.

A. Oocytes become hyperpolarized as chloride ions enter them., The membrane potential is negative. The passage indicates that the opening of GABA receptors results in entry of chloride ions inside the cell. As chloride ions have a negative charge, the entry of chloride ions into the cell will make the cytoplasm more negative thus hyperpolarizing the cell membrane.

d'Errico's argument about the Neandertals and symbolism (paragraph 3) necessarily requires which of the following? A. Proof that Neandertals used jewelry as symbols B. Proof that Neandertals invented jewelry to wear as symbols C. Proof that Neandertals copied jewelry designs from modern humans D. Proof that Neandertals traded with modern humans to obtain jewelry

A. Proof that Neandertals used jewelry as symbols Neandertals used symbols "was not qualitatively different from that of anatomically modern humans" (paragraph 3). It is the use of jewelry as symbols ("their way of using symbols"—paragraph 3) that proves that Neandertals were capable of symbolic thought, which is clearly essential to d'Errico's claim

Like other retroviruses, HIV contains reverse transcriptase, an enzyme that converts the viral genome from: A. RNA to DNA. B. DNA to RNA. C. RNA to protein. D. protein to RNA.

A. RNA to DNA.

Based on the passage, which subunit of PTx is LEAST suitable for generation of vaccine against B. pertussis? A. S1 B. S2 C. S4 D. S5

A. S1, When choosing an antigen for vaccine production, there are two aspects to consider: immunogenicity and toxicity. S1 has the ADP ribosyl transferase activity responsible for toxicity of PTx and therefore is least suitable for vaccine production

What is the main topic of the passage? A. Solutions to problems with the geographic distribution of healthcare workers in the U.S. B. Proposed revisions to the current urban and rural healthcare systems in the U.S. C. Health risks experienced disproportionately by those living in rural areas in the U.S. D. Inequities in healthcare quality based on geographic region of the U.S. Solution

A. Solutions to problems with the geographic distribution of healthcare workers in the U.S., The geographic maldistribution of health professionals is identified in the first paragraph as one of the characteristics causing limited access to health care by rural Americans

The UV-VIS spectrophotometer used by the researchers contained a detector that had low sensitivity and was unable to measure high absorbance samples. Which approach to the experiment makes the most sense with this limitation in mind? A. The experiments done at high pH should be diluted relative to those at low pH, or the path length of the high pH experiments should be decreased. B. The experiments done at low pH should be diluted relative to those at high pH, or the path length of the high pH experiments should be decreased. C. The experiments done at high pH should be diluted relative to those at low pH, or the path length of the low pH experiments should be decreased. D. The experiments done at low pH should be diluted relative to those at high pH, or the path length of the low pH experiments should be decreased.

A. The experiments done at high pH should be diluted relative to those at low pH, or the path length of the high pH experiments should be decreased, To not have an absorbance reading that is below the limits of the detector, the experiments done at pH values that result in the highest absorptivity should be diluted. The alternative is to decrease the path length of the experiments that have the highest absorptivity.

Suppose that a child persists in fearing a monster despite assurances by adults that the fear is unreasonable. Which of the following reasons for this fear would undermine the passage author's argument? A. The fear is instinctual and beyond the child's control. B. The child assumes that adults cannot see the monster. C. The child believes that the adults are untrustworthy. D. The fear is a displaced expression of separation anxiety.

A. The fear is instinctual and beyond the child's control., there is evidence that even strong emotions possess a sort of rationality—that is, they are governed by thought, and they are educable. We try to convince a child not to fear an imagined monster underneath the bed by proving that no monster is there" (paragraph 4). If, however, the child's fear persisted despite such assurances, and the fear that persisted was "instinctual and beyond the child's control," this challenge the author's claim that reason is a component of emotion and that emotion can be taught or corrected.

Which forms of guanine and thymine are favored under physiological conditions? A. The keto form of guanine and the keto form of thymine B. The keto form of guanine and the enol form of thymine C. The enol form of guanine and the keto form of thymine D. The enol form of guanine and the enol form of thymine

A. The keto form of guanine and the keto form of thymine, pka 9.2, ph is 7.2, protonated

WRONG: Which of the following aspects of the mounds described in the passage best explains archaeologists' reluctance to postulate a strictly Native American origin? A. Their apparently sudden appearance B. Their relatively early appearance C. Their size D. Their purpose

A. Their apparently sudden appearance, diffusion of the practice from some area where it was already well established seemed to be the best way to explain its apparently sudden and relatively late appearance in the eastern Woodlands of the U.S." (paragraph 2).

Which of the following statements best summarizes the fourth paragraph? A. There are many ways that writers reveal themselves in their writing. B. It makes a big difference if a writer's work is subjective and not objective. C. Most writers' lives are chaotic, and they create order through writing. D. Many writers want their lives to be visible in their written work.

A. There are many ways that writers reveal themselves in their writing., the author enumerates the different ways in which writers may reveal themselves in their work: "Some writers want to expose themselves, some to disguise themselves, some to efface themselves....There is more than one way to impose order on your personal chaos, but since good writers write what's important to them, they are bound to be in there somewhere, as participants or observers or ombudsmen.", writers reveal themselves in their work

Which of the following, if true, would most strengthen Zilhão's hypothesis (paragraph 2) regarding the ornaments found at Neandertal sites? A. They predate modern-human sites. B. There are more ornaments made of teeth than tusk. C. They look identical to ornaments found at modern-human sites. D. They are typically found at what are believed to be Neandertal burial sites.

A. They predate modern-human sites., Neandertals made the ornaments themselves (they didn't get them by trade or finding them), independent of any modern-human influence (they didn't copy them).

Why was it important that the cuvettes containing the glucose oxidase and the blood sample were identical in terms of optical properties? A. To enable the comparison of the absorption spectra B. To reduce the absorption in the glass walls C. To decrease the uncertainty in the wavelength D. To increase the absorption in the solutions

A. To enable the comparison of the absorption spectra, absorbed radiation is due only to if glucose is in the blood and not due to the difference in the absorption features of the walls

IFFY Which statement describes ATP consumption and production during the preparatory and payoff phases of glycolysis, respectively? A. Two ATP molecules consumed, four ATP molecules produced B. Four ATP molecules consumed, eight ATP molecules produced C. Four ATP molecules consumed, two ATP molecules produced D. Eight ATP molecules consumed, four ATP molecules produced

A. Two ATP molecules consumed, four ATP molecules produced

Of the events listed, which occurs first during action potential generation? A. Voltage-gated sodium channels open at the axon hillock. B. Hyperpolarization stimulates the opening of ligand-gated potassium channels. C. Graded potentials propagate along the axon. D. Calcium influx stimulates vesicle fusion and release of neurotransmitter.

A. Voltage-gated sodium channels open at the axon hillock., When threshold is met at the axon hillock, voltage-gated sodium channels open, generating an action potential

WRONG: Which conclusion can be drawn from the data presented in Figure 1? In myoblast cells: A. a biomechanical stimulus reverses the effects of inflammatory cytokines. B. NOS activity reverses the effects of inflammatory cytokines. C. inflammatory cytokines reverse the effects of L-NAME. D. NOS activity is essential for MYOD1 expression. Solution

A. a biomechanical stimulus reverses the effects of inflammatory cytokines. inflammatory cytokines (TNF-α) reduce MYOD1 mRNA levels (comparing the third column with first column). Treating cells with biomechanical stimuli (CTS) reverses the effects of inflammatory cytokines (TNF-α). This reversal is shown by comparing the fourth column with the third one

WRONG A researcher applying Watts's mathematical models as described in the passage to research on the transmission of an airborne contagious disease can most reasonably assume that: A. a small number of individuals could cause a widespread distribution of the disease. B. all infected individuals would contribute equally to the distribution of the disease. C. widespread disease transmission is more likely in a society with many isolated subcultures. D. disease transmission among individuals who do not know each other is highly unlikely.

A. a small number of individuals could cause a widespread distribution of the disease.,These "random connectors," who can be a small number of strategically connected people, can have a disproportionate impact on the possibility of transmitting the folders. This would be analogous to a small number of people helping to transmit a disease more "efficiently."

WRONG Implicit in the argument that emotions are not equivalent to feelings is the idea that emotion: A. concerns a specific object or situation. B. is genuine only if chemically induced. C. involves clear physiological changes. D. is active during the creation of art.

A. concerns a specific object or situation., The author implies that "something or someone" is necessary to make a feeling (a sensation) into an emotion, which suggests that an emotion indeed concerns a "specific object or situation."

The author describes the research of Cyrus Thomas most likely because it: A. discredits the hypothesis that mounds were built by a vanished culture. B. supports the hypothesis that people from the area that is now Mexico influenced Native American mound building. C. establishes when mound building occurred in the eastern Woodlands. D. challenges the diffusion hypothesis put forth by archaeologists.

A. discredits the hypothesis that mounds were built by a vanished culture., Cyrus Thomas had "convincingly refuted" the "long-popular idea that the mounds were the work of a vanished culture" (first paragraph)

During exercise, the osmolarity of venous blood from active muscles will increase as a result of an increase in: A. lactate concentration in plasma. B. O2 concentration in plasma. C. oxyhemoglobin concentration in red blood cells. D. blood pressure in systemic arteries.

A. lactate concentration in plasma., During exercise, muscles produce lactate that goes into circulation. The presence of lactate will increase the osmolarity of the venous blood

The passage implies that relative to art critics, film critics are: A. more forthright. B. more respected. C. less pretentious. D. less qualified.

A. more forthright., One can hardly imagine the book, film, theater, music, or even food critics of the Times succumbing to such a degree of chinlessness" (paragraph 3). The clear implication here is that film (and other reviewers) are far more direct than are the art reviewers.

Implicit in the author's discussion of Milgram's folders (paragraph 5) is the belief that: A. people will cooperate more fully if they think they are involved in something official. B. the design of the folders confused the participants. C. something more complicated than a simple chain letter does not work well in such experiments. D. going from rural areas to urban areas works best with a "folder-mailing" design.

A. people will cooperate more fully if they think they are involved in something official., Milgram attempted to explain why so few folders made it through to their intended targets by suggesting that people "didn't bother sending the letters on." But the author dismisses this line of argument: "The folder, however, was not a simple chain letter, but an official looking document with heavy blue binding and a gold logo. If the subjects knew how to reach the targets, they probably would have" (paragraph 5).

Wrong. Compound 3 is prepared from Compound 2 (Figure 2) by: A. reduction of the ketone and lactonization of the gamma-hydroxyester. B. hydrolysis of one ester and formation of an acetal from the ketoacid. C. reduction of one ester and formation of an acetal from the gamma-hydroxyketone. D. reduction of one ester and the ketone followed by dehydration to a ketoether.

A. reduction of the ketone and lactonization of the gamma-hydroxyester. 1. NaBH4 reduces the ketone to a secondary alcohol, the gamma-hydroxyester intermediate. 2. the alcohol group in this intermediate then reacts as a nucleophile with the carbonyl in the ethyl ester in the same molecule, forming a new ester by displacing C2H5OH as a leaving group. 3. This cyclic ester is called a lactone, and the intramolecular transesterification yielding this lactone is called lactonization.

Based on the passage, ACC2 is most likely compartmentalized to: A. the mitochondria. B. the cell membrane. C. the cytosol. D. the lysosome.

A. the mitochondria, involved in fatty acid oxidation

Microglia

Act as phagocytes, eating damaged cells and bacteria, act as the brains immune system

Helper T cells

Activate macrophages, B cells and T cells.

active immunity vs passive immunity

Active: exposure to foreign antigens; slow onset , cytotoxic T lymphocytes, TH1, TH2 cells, and activated B cells Passive: preformed antibodies from another host , rapid onset,

Desmosomes

Anchoring junctions that prevent cells from being pulled apart

At physiological pH, what is the net charge of the nuclear localization sequence described in the passage? A. -1 B. 0 C. +1 D. +2

B. 0, MYOD1 (NDAFEITKRC) contains three positively charged amino acids (K, R, and the N-terminal amino acid) and three negatively charged amino acids (D, E, and the C-terminal amino acid). Therefore, the net charge of this sequence at physiological pH is zero

What is the approximate energy of a photon in the absorbed radiation that yielded the data in Table 1? (Note: Use 1 eV = 1.6 × 10-19 J and hc = 19.8 × 10-26 J•m.) A. 1 eV B. 2 eV C. 3 eV D. 4 eV

B. 2 eV, The photon energy is E = hc/λ = 19.8 × 10-26 J•m/(625 × 10-9 m) = 3.1 × 10-19 J ≅ 2 eV.

What is the frequency of the pulses that deliver laser radiation to the cornea? A. 0.4 Hz B. 4.0 Hz C. 25 Hz D. 250 Hz

B. 4.0 Hz, The frequency is 1/(250 ms) = 4 Hz. 1/period

A woman with cystic fibrosis considers having children with an asymptomatic man who is heterozygous for the cystic fibrosis allele. What is probability of having a child with cystic fibrosis? A. 25% B. 50% C. 75% D. 100%

B. 50%, a homozygous individual and a heterozygous individual have 50% probability of having a child with the disorder.

What is the approximate concentration of reaction product in a solution that has an absorbance of 0.7 at pH 6.0? A. 0.50 μM B. 500 μM C. 5 mM D. 500 mM

B. 500 μM A = εbc given in the passage, the concentration c is the absorbance A divided by the absorptivity ε in a 1 cm path length cell. 0.7 divided by approximately 1400 gives 500 μM.

Roughly to what height would a 5 kg stone need to be raised in order to have the same stored energy as the energy stored in the defibrillator's capacitor? A. 4 m B. 8 m C. 16 m D. 32 m

B. 8 m, The gravitational potential energy is mass × gravitational acceleration × height. Equating 400 J = 5 kg × 9.8 m/s2 × height and solving for height leads to 400 J/(49 kg × m/s2) ≈ 8 m.​

Which of the following oxidative transformations is unlikely to occur? A. A primary alcohol to an aldehyde B. A tertiary alcohol to a ketone C. An aldehyde to a carboxylic acid D. A secondary alcohol to a ketone

B. A tertiary alcohol to a ketone, Oxidation of tertiary alcohols is difficult because it involves C-C bond breaking.

WRONG What is the main point of the first paragraph? A. A writer must be faithful to real life to be successful. B. A work of fiction reveals its creator's strengths and weaknesses. C. A writer is like a camera that perfectly reproduces real life. D. A writer's astigmatisms are what make a work of fiction fascinating.

B. A work of fiction reveals its creator's strengths and weaknesses. "The author emphasizes in the first paragraph that writers do not simply "reflect" reality in a mechanical way. Rather, each writer has a specific "lens" that informs his or her representation of reality. He concludes the paragraph: "there is no escaping the fact that fiction is only as good as its maker

Assume that cellular uptake rates and drug delivery rates of compounds 1 and 2 are identical. If the proposed mechanism of sensitization by Compound 1 is correct, what cancer cell treatment protocol is most likely to produce the most apoptosis 20 h after treatment? A. Administration of both Compound 1 and Compound 2 simultaneously B. Administration of Compound 1 followed by Compound 2 after 0.5 h C. Administration of Compound 2 followed by Compound 1 after 0.5 h D. Administration of Compound 2 followed by Compound 1 after 1 d Solution

B. Administration of Compound 1 followed by Compound 2 after 0.5 h, NF-κB signaling pathway is anti-apoptotic and is initiated by degradation and release of the inhibitor binding protein IκB. Once started, this process is not easily reversed. If the chemotherapeutic agent is administered at the same time as the sensitization agent, there is good reason to believe that some cells will be exposed to Compound 2 prior to Compound 1 as a result of random probability. The researchers found that administration of Compound 1 prior to Compound 2 by 0.5 h provided benefit.

Which of the following functional groups is present in pyrrolizidine (Figure 1)? A. An amide B. An amine C. An imine D. A carbamate

B. An amine, Pyrrolizidine contains a nitrogen atom bonded to three noncarbonyl carbon atoms, which is an amine. An amine is defined as R3N, where R = H or a carbon group (but NOT C=O) and no more than two out of three R groups can be H.

If cord-marked Woodland pottery were found in areas between the Bering Strait and the eastern Woodlands, this would support the notion that mound building diffused from: A. Europe. B. Asia. C. Scandinavia. D. Mexico.

B. Asia., If, however, cord-marked Woodland pottery were found precisely in the intervening regions (between the Bering Strait and the Eastern Woodlands), this would presumably remedy that "problematic" lack of evidence and offer support for the theory that the mound-building had also diffused from Asia

Which of the following atoms gains one electron most readily? A. Ar B. Br C. Co D. Na

B. Br, Atoms positioned to the right of the Periodic Table tend to gain electrons more readily than the metallic elements on the left, with the exception of Group 18. Bromine, Br, is a member of the Group 17 halogen family and gains an electron readily.

Which of the following events does the release of CCK likely trigger? A. Relaxation of muscle in wall of gallbladder and relaxation of hepatopancreatic sphincter B. Contraction of muscle in wall of gallbladder and relaxation of hepatopancreatic sphincter C. Relaxation of muscle in wall of gallbladder and contraction of hepatopancreatic sphincter D. Contraction of muscle in wall of gallbladder and contraction of hepatopancreatic sphincter Solution

B. Contraction of muscle in wall of gallbladder and relaxation of hepatopancreatic sphincter, The passage states that in the presence of CCK, more bile is released. For this to happen, the smooth muscles around the gall bladder will have to contract, and the hepatopancreatic sphincter will have to relax.

wrong, Which variant of DNA polymerase will most likely retain catalytic activity? A. D429A B. D429E C. D429K D. D429F

B. D429E, Since the side chain carboxylate groups bind the metal ions, the only variant that would retain this function is D429E.

The electric field inside each of the conductors that forms the capacitor in the defibrillator is zero. Which of the following reasons best explains why this is true? A. All of the electrons in the conductor are bound to atoms, and thus there is no way for an external electric field to penetrate atoms with no net charge. B. Free electrons in the conductor arrange themselves on the surface so that the electric field they produce inside the conductor exactly cancels any external electric field. C. Free electrons in the conductor arrange themselves on the surface and throughout the interior so that the electric field they produce inside the conductor exactly cancels any external electric field. D. All electrons in the conductor, both free and bound, arrange themselves on the surface so that the electric field they produce inside the conductor exactly cancels any external electric field.

B. Free electrons in the conductor arrange themselves on the surface so that the electric field they produce inside the conductor exactly cancels any external electric field., Conductors contain both atom-bound electrons and free electrons. Free electrons arrange themselves on the surface of conductors, and their collective electric field produced inside the conductor cancels any external electric field.

Which technique separates proteins independently of their charge? A. Native PAGE B. Gel filtration chromatography C. Ion exchange chromatography D. Isoelectric focusing Solution

B. Gel filtration chromatography, separates protein only on the basis of their size

Which of the following hypotheses best accounts for the differences in the level of circulating ghrelin in individuals who are obese with no underlying condition and this level in individuals who are lean? A. The hypothalamus secretes less ghrelin in individuals who are lean because their metabolic needs are greater than those of individuals who are obese. B. Ghrelin secretion is suppressed in individuals who are obese because their bodies have greater energy stores than do the bodies of individuals who are lean. C. The hypothalamus secretes more ghrelin in individuals who are lean because their metabolic needs are less than those of individuals who are obese. D. Ghrelin secretion is suppressed in individuals who are obese because their bodies have fewer energy stores than do the bodies of individuals who are lean. Solution

B. Ghrelin secretion is suppressed in individuals who are obese because their bodies have greater energy stores than do the bodies of individuals who are lean., Obese individuals have more energy stores than lean individual. For this reason, the levels of ghrelin, which increases appetite, are lower in obese individuals.​

The function of Na+/K+ ATPase is to transport: Na+ out of cells against its concentration gradient. Na+ into cells with its concentration gradient. K+ out of cells with its concentration gradient. K+ into cells against its concentration gradient. A. I and III only B. I and IV only C. II and III only D. II and IV only

B. I and IV only, The Na+/K+ ATPase, or sodium/potassium pump is an active transporter that pumps sodium and potassium ions through the membrane against their concentration gradient to maintain osmotic pressure.

WRONG For which of the following questions does the passage fail to provide any information about Spencer's likely response? A. If Spencer's audience believed him to be a staunch advocate of capitalist culture, did they fully grasp his ideas? B. If the government doesn't build sewer systems, who should build them? C. If a country has many affluent people, why shouldn't they help the less affluent ones? D. If people want to be wealthy, why shouldn't they work tirelessly until they achieve wealth?

B. If the government doesn't build sewer systems, who should build them? "[g]overnments had no obligation, or even right, to compel vaccination or education, keep small children from sweeping chimneys, mandate the construction of sewers, or relieve poverty" (paragraph 6).

WRONG: If a researcher studying rumor transmission among individuals were to use the same methodology as that of Milgram's small-world experiment, which of the following actions would be part of the methodology? A. Making sure starters and targets are located in the same city B. Ignoring cases in which a starter does not repeat the rumor C. Offering a financial incentive for completed rumor transmissions D. Submitting the data to mathematicians for analysis

B. Ignoring cases in which a starter does not repeat the rumor, ultimate targets in his published studies was that "people didn't bother sending the letters on" (paragraph 5). Milgram attempts to discount such situations, rather than seeing them as presenting a problem with his theory itself. This would be analogous to a situation in which researchers overlooked, or ignored, those people who did not repeat a rumor.

Which of the following best describes the relationship of the reference to Talley (paragraph 2) to the passage as a whole? A. It questions the importance of a previously mentioned problem. B. It supports a previously mentioned solution. C. It enables critique of a scenario mentioned later in the passage. D. It provides understanding of a paradox mentioned later in the passage.

B. It supports a previously mentioned solution., the four parts of the Talley reference support that solution, providing evidence suggesting the solution will succeed.

Which of the following explains why increasing the initial concentration of pyruvate will cause an increase in the equilibrium concentration of acetylphosphate? A. Reaction spontaneity B. Le Châtelier's principle C. Heat released by the reaction D. The increase in free energy

B. Le Châtelier's principle, increasing the concentration of a reactant (pyruvate) will increase the concentration of a product (acetylphospate) at equilibrium.

Based on the information in the passage, compounds 1-3 are what type of inhibitor? A. Competitive B. Mixed C. Product D. Irreversible

B. Mixed, compounds 1-3 can bind to RT both before and after the substrate has bound. Also, the compounds do not exclude substrate binding. Therefore, mixed inhibition is most likely.

A carbonyl group contains what type of bonding interaction(s) between the C and O atoms? A. One σ only B. One σ and one π only C. One π only D. One σ and two π only

B. One σ and one π only, C=O double bond. The first bonding interaction between atoms is always a σ bond. The second bond is formed from π symmetry orbitals.

The nuclear localization sequence of MYOD1 contains how many potential phosphorylation sites? A. None B. One C. Two D. Three

B. One, There are three amino acids that are phosphorylated in eukaryotes: serine (S), threonine (T), and tyrosine (Y). The nuclear localization sequence of MYOD1 (NDAFEITKRC) contains one threonine (T) that can potentially be phosphorylated.​

Which pathway depicts the sequence of cellular compartments traversed by newly synthesized GABA-receptor subunits as they move to the cell surface? A. Rough endoplasmic reticulum, endosome, and Golgi complex B. Rough endoplasmic reticulum, Golgi complex, and secretory transport vesicle C. Golgi complex, endosome, and lysosome D. Golgi complex, rough endoplasmic reticulum, and secretory transport vesicle

B. Rough endoplasmic reticulum, Golgi complex, and secretory transport vesicle, As GABA receptors are located in the cell membrane, they will be synthesized in the RER, modified in the Golgi apparatus, and transported to the membrane by transport vesicles.

Some theater critics disdain the popularity of the "golden age" Broadway musicals, preferring less accessible theater that they would designate as "high art." How would this view most likely be regarded by the passage author? A. The passage equation of commodity and golden age musicals suggests that the author would agree with the critics. B. The passage discussion of golden age musicals suggests that the author would regard these critics as unnecessarily dismissive. C. The passage discussion of the "common musical language" of the non-commodity musical suggests that the author would be aligned with these critics. D. The passage position on the cost of contemporary Broadway theatrical productions suggests that the author would reject the critics' views.

B. The passage discussion of golden age musicals suggests that the author would regard these critics as unnecessarily dismissive., very much likes the "old-fashioned Broadway musical, with its optimism and burgeoning musical energy" (final paragraph), and laments its demise. The author also talks about the rooting of the "golden-age' musical" in what he or she calls a "universally popular musical language" (paragraph 4). The author, then, does not dismiss the popular; the author dismisses the inauthentic and clearly derivative.

What is the effect produced by the PRK technique designed to correct nearsightedness? A. The density of the cornea is increased. B. The radius of curvature of the cornea is increased. C. The index of refraction of the cornea is increased. D. The thickness of the cornea at the apex is increased. Solution

B. The radius of curvature of the cornea is increased., According to the passage, to correct nearsightedness, the laser beam is directed onto the central part of the cornea, resulting in a flattening of the cornea. This means that the radius of curvature of the cornea is increased.

Why does the author most likely mention 9 to 5 (paragraph 2)? A. To make a point about the titles of commodity musicals B. To illustrate the closeness of adaptations to sources in commodity musicals C. To indicate that casting is the most important element of a successful adaptation D. To provide an example of a Broadway musical that was based on a Hollywood movie

B. To illustrate the closeness of adaptations to sources in commodity musicals, "The shows may also be cast to evoke their source material: the stars of the stage version of 9 to 5, for example, bore an unmistakable resemblance to their on-screen models" (paragraph 2).

Which transition produces a photon with the longest wavelength? A. Transition 1 B. Transition 2 C. Transition 3 D. Transition 4

B. Transition 2, The separation between the energy level equals the energy of the photon. The energy of the photon is inversely proportional to the wavelength. The longest wavelength corresponds to the smallest photon energy, which corresponds to the transition between the closest energy levels.

Which of the following, if true, would most weaken Shea's hypothesis regarding wood-tipped and stone-tipped spears (paragraph 5)? A. Stone-tipped spears are more durable than wood-tipped spears. B. Wherever both types of spears are found, only one kind of prey animal is found. C. Wherever Neandertal sites are found, there is a variety of crafting tools as well as hunting tools. D. Both wood-tipped and stone-tipped spears are found in modern-human archaeological sites.

B. Wherever both types of spears are found, only one kind of prey animal is found., Neandertal sites shows both wood-tipped spears and stone-tipped spears, yielding the hypothesis that each type of tool was for a different kind of prey" (paragraph 5). If there was only one type of prey found, this would clearly weaken the hypothesis that the tools were crafted for different kinds of prey

Ca(OH)2 and CaCl2 in the reaction shown in Equation 1 are best described as compounds of: A. an alkali metal. B. an alkaline earth metal. C. a metalloid. D. a transition metal. Solution

B. an alkaline earth metal., Group 2 of the Periodic Table. Calcium, Ca, is a member of this family found in period 4

Based on the passage, it can be reasonably inferred that the intelligentsia accepted Milgram's theory because it: A. was adopted by the media and movies. B. appealed to their imaginations. C. could be modeled mathematically. D. ignored race and class boundaries.

B. appealed to their imaginations., "Milgram's findings slipped away from their scientific moorings and into the world of imagination. The idea of six degrees of separation was adopted by the intelligentsia..." (paragraph 2).

IFFY Bacteriophages were labeled with radioactive phosphorous (32P) and sulfur (35S). The labeled bacteriophages were then allowed to infect their host cells. At the end of the experiment, the 32P label was found only inside the host cells and the 35S label was found only outside the host cells. This experiment shows that: A. bacteriophages consist only of DNA and protein. B. only DNA, not protein, can enter the host cell. C. only protein, not DNA, can enter the host cell. D. both DNA and protein can enter the host cell.

B. only DNA, not protein, can enter the host cell., 32P and 35S incorporate into DNA and proteins, respectively., only the bacteriophage DNA enters the cell, not proteins

Assume that a certain individual has no underlying metabolic disorder and has a normal ghrelin response. Given this, what would most likely happen to this individual's fasting level of circulating ghrelin if the individual were to first gain, then lose, a significant amount of weight by natural methods? The fasting level of circulating ghrelin would: A. increase as the individual gained weight, then decrease as the individual lost weight. B. decrease as the individual gained weight, then increase as the individual lost weight. C. increase as the individual gained weight and remain high as the individual lost weight. D. decrease as the individual gained weight and remain low as the individual lost weight.

B. decrease as the individual gained weight, then increase as the individual lost weight., the levels of circulating ghrelin are the opposite of the amount of weight gained. They are low when the individual gains weight and high when the individual loses weight

Based on the passage, as compared to a wild-type mouse, an Acc2-/-/Cpt1-/- double knockout mouse is most likely to exhibit: A. increased insulin secretion. B. decreased fatty acid oxidation. C. decreased triglyceride synthesis. D. increased malonyl-CoA production.

B. decreased fatty acid oxidation., CPT1 is an enzyme in the carnitine shuttle, transporting fatty acids into the mitochondria for oxidization. The absence of CPT1 would prevent the transport of fatty acids into the mitochondria for oxidization

In Plato's opinion as the passage author represents it, the relationship of emotion to reason is most like that of: A. paint to painting. B. disease to health. C. body to soul. D. water to ice.

B. disease to health., author's description, Plato clearly sees the "controlled" state that reason brings as the desirable (or healthy) state, and the "irrational" role of emotion as the disease that threatens health.

The specific mention by name of Promises, Promises (paragraph 3) is: A. ironic. B. incidental. C. dismissive. D. significant.

B. incidental., author is only making a point about ticket prices, the point is dependent on the year that play opened

WRONG The passage author's assertions imply that concern about undesirable social effects would be justified by a: A. tragic play that induces grief and horror. B. novel that promotes belief in demonic possession. C. political play that incites anger at authorities. D. lyrical poem that arouses sensual desires.

B. novel that promotes belief in demonic possession., the only danger of art to society is not that it excites the passions, but that it may instill false beliefs" (final paragraph). A novel that promotes belief in demonic possession would, of course, be an instance of a work of art "instilling false beliefs" and would justify the author's concern about the undesirable social effects of art.

The negative control used in Experiment 1 was most likely: A. unconditioned media without AECs. B. unconditioned media with AECs. C. conditioned media without AECs. D. conditioned media with AECs.

B. unconditioned media with AECs., the one that is performed in the conditions that are not expected to give positive results. Thus, unconditioned media will need to be used. As antibodies are highly specific, if 53BP1 and γH2AX are detected in the negative control, this means that AEC are present.

In a different experiment, healthy human volunteers received an intravenous infusion of 100 mL of hyperosmotic NaCl solution, which induced thirst and a desire to drink. In this experiment, thirst probably was stimulated via: A. blood volume receptors, as a result of increased blood volume after the infusion. B. osmoreceptors, as a result of increased blood osmolarity after the infusion. C. a sensation of dryness in the mouth by oral receptors. D. the NaCl itself, because salt makes a person thirsty regardless of osmolarity.

B. osmoreceptors, as a result of increased blood osmolarity after the infusion, Osmoreceptors are activated by the increase in osmolarity of the blood. This process triggers the sensation of thirst.

Limestone does NOT decompose when heated to 900 K because, at 900 K, ΔH is: A. positive and less than TΔS. B. positive and greater than TΔS. C. negative and less than TΔS. D. negative and greater than TΔS.

B. positive and greater than TΔS., the reaction does not occur, ΔG = ΔH - TΔS > 0. From inspection of the reaction, it can be concluded that ΔS > 0 (a gas evolves). Consequently, ΔH > TΔS explains why the reaction does not occur

By stimulating secretion of peptidases from the pancreas into the duodenum, CCK facilitates the digestion of: A. fats. B. protein. C. nucleotides. D. carbohydrates.

B. protein., Peptidases are enzymes that digest proteins.

The osmolarity of urine in these subjects was 958 milliosmoles/L, compared with an average blood osmolarity of 284 milliosmoles/L. The higher osmolarity of urine suggests that: A. the kidneys are secreting very little Na+. B. the kidneys are acting to conserve water. C. the subjects are on a low-protein diet. D. the subjects are dehydrated.

B. the kidneys are acting to conserve water., increase in water conservation would result in higher urine osmolarity and lower blood osmolarity.

WRONG The passage suggests that the "national virtue" Spencer had assaulted during his banquet speech was U.S. residents' tendency: A. to give large amounts of money to charities. B. to devote large amounts of time to pursuing a livelihood. C. to believe that competition, rather than hard work, brings wealth. D. to be ostentatious in displaying their wealth.

B. to devote large amounts of time to pursuing a livelihood., Spencer told his admirers that they had seriously misunderstood him. He did not approve of the culture of American capitalism.... He felt that for Americans, work was a pathological obsession that endangered mental and physical health" (paragraph 4).

The passage argument implies that socially responsible drama: A. does not generate negative attitudes and feelings. B. uses people's feelings to stimulate their thought. C. evokes people's culture-specific emotions. D. purges people of unhealthy emotions.

B. uses people's feelings to stimulate their thought. writes that "the reactive component of emotion may serve the reflective component by directing attention to information of importance to us" (paragraph 5)

WRONG Suppose that psychological studies show that novels arouse emotion only if readers consider the characters and situations described realistic. What is the relevance of this finding for the passage author's conclusions? A. It affirms them by implying an irrationality that serves human survival. B. It affirms them by implying a reasoned engagement with the narrative. C. It violates them by implying a logically unjustified emotional response. D. It violates them by implying that this form of art opposes reason.

B. It affirms them by implying a reasoned engagement with the narrative., "the emotions elicited by art do not subvert human reason, since reason—memory, associative conceptualization, judgment—is an inextricable constituent, indeed a determining force, of such responses" (final paragraph).

WRONG For which of the following passage statements is evidence NOT provided? A. "Although this kind of intervention [changing the medical education system so that it selects, trains, and deploys more health care workers who choose to practice in rural areas] does not lend itself to controlled experiments, ample evidence exists that such an approach works" (paragraph 2). B. "[P]hysicians and others act as rational economic beings" (paragraph 3). C. "These two federal programs [community health centers and the National Health Service Corps] remain the preeminent safety net programs for rural America" (paragraph 4). D. "Currently, telemedicine is dynamic, but relatively unstructured" (paragraph 5).

C. "These two federal programs [community health centers and the National Health Service Corps] remain the preeminent safety net programs for rural America" (paragraph 4)., There is no evidence for this claim, no illustration of its preeminence as a safety net

NH3 acts as a weak base in water with Kb = 1.76 × 10-5 at 25°C. The corresponding equilibrium is shown below. NH3(aq) + H2O(l) ⇌ NH4+(aq) + OH-(aq) At 25°C, the equilibrium concentration of the NH4+ ion in a 10 M aqueous solution of NH3 would be closest to which of the following? A. 0.001 M B. 0.01 M C. 0.1 M D. 1 M

C. 0.1 M, Kb = 1.76 × 10-5 = [NH4+][OH-]/[NH3]. Plugging in 10 M for [NH3], which is a good approximation since very little NH3 ionizes, and noting that [NH4+] = [OH-], it is possible to solve for [NH4+]: 1.76 × 10-5 = [NH4+]2/10 → 1.76 × 10-4 = [NH4+]2 → 1.32 × 10-2 = [NH4+].

What is the [H3O+] in the solution used in the experiment done at the lowest pH? A. 0.01 μM B. 0.1 μM C. 1.0 μM D. 100 μM

C. 1.0 μM, The lowest pH is 6. Because pH = -log([H3O+]), [H3O+] = 1.0 × 10-6 M or 1.0 μM.

How many hydrogen bonds are present in the two types of G•T mismatches discussed in the passage? A. 2 in the wobble pair, 2 in the enol T mismatch B. 3 in the wobble pair, 2 in the enol T mismatch C. 2 in the wobble pair, 3 in the enol T mismatch D. 3 in the wobble pair, 3 in the enol T mismatch

C. 2 in the wobble pair, 3 in the enol T mismatch, wobble base pair appears as an offset A•T pair, it has two hydrogen bonds. The G•C mimic mismatch would have three hydrogen bonds.

The specific heat of liquid water is 4.2 kJ/°C•kg. How much energy does it take to heat 2 kg of water from 20°C to 70°C? A. 220 kJ B. 320 kJ C. 420 kJ D. 520 kJ

C. 420 kJ q= mcdelta t= 2 kg × 4.2 kJ/°C•kg × 50°C = 420 kJ.

What is the concentration of the acute leukemia CC95 Combination value in micromolar (μM) units? A. 6 × 10-10 μM B. 6 × 10-7 μM C. 6 × 10- 4 μM D. 6 × 10-2 μM

C. 6 × 10- 4 μM, The CC95 Combination value for acute leukemia cells was 0.6 nM, or 0.6 × 10-9 M. This corresponds to 0.6 × 10-9 M × (1 μM/1 × 10-6 M) = 0.6 × 10-3 μM = 6 × 10-4 μM.

A peptide consisting of nine amino acids was partially hydrolysed. Three different tripeptides were isolated. None of the tripeptides share a common amino acid. Based on the data, what is the total number of possible structures possible for the full-length peptide? A. 3 B. 4 C. 6 D. 27

C. 6, ABC, DEF, and GHI, they can only be joined in 6 different possible ways to make a nonapeptide. Each of the tripeptides can appear in the first position and can combine in two possible ways with the other two tripeptides: 3 × 2 = 6

The researchers want to generate a mutant mouse strain that expresses a constantly active variant of ACC2 by replacing the amino acid at position 212 with a different residue. Which residue is the best choice as a replacement? A. Tyrosine B. Serine C. Alanine D. Threonine

C. Alanine AMPK inactivates ACC2 through phosphorylation of the residue at position 212. Of all the amino acids listed, only alanine cannot be phosphorylated, making it a constantly active variant

Which of the following responses could maintain cardiac output under dehydration conditions that reduce blood volume? A. A decrease in stroke volume B. A decrease in heart rate C. An increase in heart rate D. An increase in blood viscosity

C. An increase in heart rate, The heart rate is the number of heart contractions per minute. An increase in heart rate would maintain the cardiac output in dehydration conditions.

WRONG: The information in the passage best supports the hypothesis that which of the following defects accounts for excessive eating by people who have bulimia? A. Fewer CCK-sensitive vagal afferent nerves B. Excess bile release in response to CCK C. Decreased release of CCK in response to food D. Hypersensitivity to the presence of CCK

C. Decreased release of CCK in response to food, no negative feedback that can give the sensation of satiety.

WRONG: Substituting the residue at position 54 of BvgA with which amino acid will LEAST likely prevent the expression of the PTx operon? A. Glycine B. Asparagine C. Glutamate D. Alanine

C. Glutamate, residue at position 54 of BvgA is an aspartate (D54). glutamate and aspartate both carry a negative charge at physiological pH

Eating suppresses ghrelin secretion. However, this suppression does not appear to be caused by the presence of food in the stomach or duodenum, nor by stomach distension. Given this, which of the following physiological conditions is likely to suppress ghrelin secretion following a meal? A. Increased levels of circulating glucagon B. Decreased osmolarity in the ileum C. Increased levels of circulating insulin D. Decreased levels of circulating insulin

C. Increased levels of circulating insulin, levels of circulating insulin will increase after a meal due to an increase in blood glucose levels.

Which of the following statements best applies to the inactive X chromosome in mammalian females? A. It does not replicate. B. Its chromatin structure is less condensed than that of an active X chromosome. C. It is one of the last chromosomes to replicate. D. It is highly transcribed.

C. It is one of the last chromosomes to replicate.

Given that Tris has a pKa of 8.07, for how many of the experiments would Tris have been an acceptable buffer? A. None of the experiments B. Only 1 of the experiments C. Only 2 of the experiments D. All three of the experiments

C. Only 2 of the experiments, A buffer has a buffering capacity that is ±1 pH unit away from the pKa, which means that only two of the experiments would have used Tris.

A researcher measures the concentration of CO2(aq) in a solution at equilibrium. Which additional quantity must be measured in order to calculate the Henry's Law constant kH for the gas? A. Atmospheric pressure B. Volume of the solvent C. Partial pressure of the gas D. Vapor pressure of water

C. Partial pressure of the gas, Henry's Law constant kH relates the solubility of a gas S to the pressure of that gas Pg above the solution and is written as S = kH•Pg.

Which amino acid residue in the pilin subunit is most likely modified by PptB? A. Cysteine B. Phenylalanine C. Serine D. Tryptophan

C. Serine, PptB is a phosphotransferase. Of the amino acid options, only serine can be modified by a phosphotransferase.

Which of the following statements best conveys the main point of the passage? A. The Neandertals did not actually disappear. B. The Neandertals invented jewelry and hunting. C. The emerging view depicts Neandertals as having a capacity for creative, flexible behavior. D. Most researchers credit Neandertals with being well-adapted creatures who survived the cold climate of Europe.

C. The emerging view depicts Neandertals as having a capacity for creative, flexible behavior., passage focuses on challenging the portrayal of Neandertals as "lacking the language skills, foresight, creativity, and other cognitive abilities of modern humans" (first paragraph)

WRONG: Which of the following of the archaeologists' assumptions described in paragraph 3 is NOT supported by evidence or reasoning in the passage? A. The mound builders had a large labor force. B. The mound builders had ample leisure time. C. The mound builders grew maize, beans, and squash. D. The mound builders included specialized craftspeople.

C. The mound builders grew maize, beans, and squash., provides reasoning for the assumption that the mound builders were farmers but does not provide reasoning or support for the assumption that they were "farmers who grew maize, beans, and squash" (paragraph 3)

WRONG What idea about art critics does the author mean to convey by the statement: "This mindset begins to make sense when one considers that critics have traditionally missed the point about the best art of their generation" (paragraph 4)? A. They are indifferent to the goals of particular artists today. B. They are too impressed by creativity to appreciate good art. C. They are afraid to commit themselves to definite opinions. D. They are unaware of the standards usually applied to art. Solution

C. They are afraid to commit themselves to definite opinions., "timidity...of art criticism of our day" (paragraph 3) comes out of a fear of misunderstanding or overlooking art that may come to be evaluated by future generations as "great art."

Suppose it is true that the expression "survival of the fittest" was originally coined by Spencer and later adopted by Darwin. Is this fact relevant to any of the ideas in the passage? A. No; it has no relevance because the expression is not mentioned in the passage. B. Yes; it weakens the claim that Darwin restricted his theories to the biological domain. C. Yes; it supports the characterization of Darwin as a "biological Spencerian." D. Yes; it supports the university president's praise of Spencer's "powerful intellect."

C. Yes; it supports the characterization of Darwin as a "biological Spencerian." "Spencer was well-known as an evolutionist long before Darwin's On the Origin of Species was published, but while Darwin resisted applying the idea to morals, society, or politics, Spencer saw evolution working everywhere. He has been tagged as a social Darwinist, but it is more correct to think of Darwin as a biological Spencerian"

When limestone is heated during Step 1, an equilibrium is established. Which of the following expressions is the equilibrium constant for the decomposition of limestone? A. [CaO] B. [CaCO3] C. [CO2] D. [CaO] × [CaCO3]

C. [CO2], solids are excluded from equilibrium constant expressions. CO2(g), as the only non-solid material in the reaction, is the only substance that appears in the equilibrium constant expression. The exponent for [CO2] is 1 because the stoichiometric coefficient that appears in the presented balanced reaction is 1

Wrong, Based on the passage, what is the primary type of interaction that RT makes with Compound 2? A. Covalent B. Hydrogen bonds C. Ionic D. Hydrophobic

D. Hydrophobic, strongest RT interactions with the inhibitors come from the side chains of valine and phenylalanine. These side chains are hydrophobic, so they would make hydrophobic interactions with the inhibitor.

The intermolecular forces that exist among the molecules of NH3 gas are: A. dipole-dipole forces only. B. London dispersion forces only. C. both dipole-dipole and London dispersion forces. D. neither dipole-dipole nor London dispersion forces.

C. both dipole-dipole and London dispersion forces., Since NH3 is a permanent dipole, it will exhibit dipole-dipole intermolecular forces in addition to the London dispersion forces exhibited by all molecules

A defining characteristic of proteins that act as transcription factors (such as STAT5b) is that they: A. can dimerize. B. can phosphorylate other proteins. C. contain a DNA binding domain. D. are present within the nucleus of the cell.

C. contain a DNA binding domain., transcription factor has a DNA-binding domain that allows it to bind to regulatory nucleic acid sequences in a gene to alter transcription.

WRONG: Based on the passage, the author most likely believes that community health centers and the National Health Service Corps may be: A. preferable to the health options created through the free market. B. underutilized in many rural areas. C. controversial, complex, and expensive. D. providing services that recipients are not necessarily entitled to.

C. controversial, complex, and expensive., Paragraph 2 says that "federal or state delivery systems...may be controversial, complex, and expensive," and paragraph 4 describes community health centers and the NHSC as federal programs

Wrong, The Na2CO3 used in Step 5 of Figure 3 is necessary to: A. dissolve the bromoester. B. remove an α-hydrogen from the bromoester. C. convert the ammonium salt in Compound 4 to the amine. D. replace the chloride ion in Compound 4 with the carbonate ion.

C. convert the ammonium salt in Compound 4 to the amine., Until a proton is removed from the alkylammonium salt in Compound 4, it does not have the lone pair needed to be a nucleophile. As a nucleophile, Compound 4 performs the SN2 reaction that furnishes Compound 5.

IFFY As blood passes through actively contracting skeletal muscle tissue, the affinity of hemoglobin for oxygen in the muscle tissue: A. increases as a result of an increase in plasma temperature. B. increases as a result of an increase in plasma PO2. C. decreases as a result of a decrease in plasma pH. D. decreases as a result of a decrease in plasma PCO2.

C. decreases as a result of a decrease in plasma pH., Affinity would decrease with a decrease in plasma pH, and during prolonged exercise, anaerobic respiration would decrease the plasma pH

What aspect of the commodity musical does the author most rely on in characterizing it in the last sentence? The author views the commodity musical as: A. innovative. B. ambiguous. C. derivative. D. ambitious.

C. derivative., calls the commodity musical both "watered-down," and a "parasitical imitation of the real thing," which is another way of saying highly derivative.

If a thin thread is placed between a screen and a bright source of light, a pattern of parallel dark and bright fringes appears on the screen. The phenomenon best explaining the formation of this pattern is: A. refraction. B. polarization. C. diffraction. D. reflection.

C. diffraction., The thin thread disrupts the propagation of light by impeding light to pass through it. Diffraction causes the initially plane-parallel wave-fronts of light to change direction and partially enter the shadow region behind the thread due to its narrowness. The overlapping of different wave-fronts on the screen causes the pattern of dark and bright fringes on the screen according to the phase difference between the wave-fronts that interfere there.

If the third codon in the coding region of the Rdl GABA receptor cDNA is replaced with an amber codon (for example, TAG) and the modified Rdl GABA receptor cDNA is expressed in frog oocytes, functional full-length receptors will: A. accumulate in the Golgi complex. B. accumulate in the rough endoplasmic reticulum. C. not be synthesized. D. lose resistance to dieldrin.

C. not be synthesized.,amber codon is a stop codon. If the third codon is replaced with a stop codon, the protein will not be synthesized.

Suppose that some influential American critics have always expressed strong opinions about the characteristics of good art and of bad art. This supposition implies that the passage author has probably: A. correctly assessed the gullibility of the American public. B. misunderstood the comments made in the Times reviews. C. overestimated the influence of criticism on artists. D. underestimated the merits of recent American art.

C. overestimated the influence of criticism on artists., But whatever the history of our artistic recession, its immediate cause is precisely the pervasive and unchecked reverence in which art is held by the critics" (paragraph 3)

Most cytochrome P450 enzymes alter the activity of drugs by: A. phosphorylating them. B. dephosphorylating them. C. oxidizing them. D. reducing them.

C. oxidizing them, Cytochrome P450 acts as monooxygenases, where an oxygen atom is inserted into a substrate (the drug of interest), thereby resulting in the oxidation of the substrate

WRONG Hormone replacement therapy is often given to children who have Prader-Willi syndrome once they have reached the hyperphagic stage. Based on the passage, the most likely reason for this therapy would be to prevent: A. giantism. B. weight loss. C. short stature. D. muscle rigidity.

C. short stature. Prader-Willi syndrome is characterized by growth hormone deficiency. Thus, hormone replacement therapy will prevent short stature

Passage context suggests that when Spencer came to the United States in 1882, he probably planned to: A. write a book about his experiences. B. introduce modifications to his theory. C. spend much of his time alone. D. leave again within a short time.

C. spend much of his time alone., needed to "reorganize his nervous system"

The author assumes that the diffusion of squash throughout the Woodlands region: A. occurred alongside the diffusion of pottery. B. is evidence of its hardiness. C. was not due to Mexican influence. D. explains why maize was not discovered at Poverty Point.

C. was not due to Mexican influence., author writes that "While squash might have been grown [in Louisiana's Poverty Point region], its presence at Poverty Point does not indicates a close relationship to Mexico because squash had diffused throughout the southeastern Woodlands region as early as 2000 BC" (final paragraph).

B cells

Cells manufactured in the bone marrow that create antibodies for isolating and destroying invading bacteria and viruses.

Wrong: According to Figure 1, as the embryo begins gastrulation, the number of cells is between: A. 4 and 6. B. 6 and 40. C. 40 and 10,000. D. 10,000 and 100,000.

D. 10,000 and 100,000., cell division just starts to slow down after the 10,000-cell stage, which corresponds to the value of 4 in the y-axis of the graph. For this reason, gastrulation should start between 10,000 and 100,000 cells.

According to Table 1, what is the concentration of the glucose in the blood from which the diluted sample was taken? A. 60 mg/dL B. 90 mg/dL C. 120 mg/dL D. 150 mg/dL

D. 150 mg/dL, From Table 1, the glucose concentration in the diluted sample is (0.20/0.24) × 6.0 mg/dL = 5.0 mg/dL. The blood then has a glucose concentration of 30 × 5.0 mg/dL = 150 mg/dL., multiplied by 30 bc 1/30 dilution ratio

An unknown amount of a radioactive isotope with a half-life of 2.0 h was observed for 6.0 h. If the amount of the isotope remaining after 6.0 h was 24 g, what would the original amount have been? A. 3 g B. 4 g C. 144 g D. 192 g

D. 192 g , Given the half-life T = 2 h, the duration t = 6 h represents 3 half-lives because 2 h × 3 = 6 h. According to the radioactive decay law N(t) = N0(1/2)t/T, the amount of remaining isotope is (1/2)3 = 1/8 of the original amount. The original amount was then 8 × 24 g = 192 g.

Which compound is predicted to mimic the effect of exercise in undifferentiated muscle cells in vivo? A. An MYOD1-specific microRNA B. An activator of NOS expression C. A repressor of Cdkn1a expression D. An antagonist of TNF-α signaling

D. An antagonist of TNF-α signaling, The figure also shows that TNF-α downregulates the MYOD1 mRNA levels, inferring that it is a negative regulator of muscle cell differentiation. Therefore, it can be predicted that an antagonist of TNF-α (a negative regulator muscle cell differentiation) would mimic the effect of exercise (a positive regulator of muscle cell differentiation)

WRONG What result would be most predictable if conditions analogous to those described in the passage prevailed in the automobile industry? A. Manufacturers would try to hide any problem associated with a model. B. Consumers would rely on personal experience to compare the models. C. Consumer advocates would report the defects of unreliable models. D. Automobile ratings would emphasize the advantages of each model.

D. Automobile ratings would emphasize the advantages of each model., "The most striking feature of recent artistic discourse, the quality that sets it apart from all earlier discussion, is its chronic unwillingness to address the weaknesses inherent in the productions of our artists" (paragraph 3).

wrong, Based on the data in Table 1, what are the effects of increasing pH on catalytic efficiency and the maximum velocity of the reaction? A. Both the catalytic efficiency and the maximum velocity of the reaction increase. B. The catalytic efficiency increases with pH, but the maximum velocity of the reaction decreases. C. The catalytic efficiency decreases with pH, but the maximum velocity of the reaction increases. D. Both the catalytic efficiency and the maximum velocity of the reaction decrease.

D. Both the catalytic efficiency and the maximum velocity of the reaction decrease., As pH increases, the kcat decreases because it is proportional to the Vmax. Also, the catalytic efficiency (kcat/KM) decreases because Vmax/KM is decreasing.​

Which of the following is most like the current situation on Broadway, as it is described in the passage? A. Popular vocalists are more successful when they incorporate dance moves into their performances. B. Art museum curators prefer collections that are positive or inspiring in some way. C. Most comedians perform in small, little-known venues before moving into larger, more prestigious venues. D. Concert programmers put only one innovative work into an evening's program of otherwise familiar classical pieces.

D. Concert programmers put only one innovative work into an evening's program of otherwise familiar classical pieces., that original shows simply cannot flourish on Broadway because audiences want what they are already familiar with, including "the presence of a movie or television star" (paragraph 6). The author also indicates that it is difficult for songwriters to work on Broadway "without conforming to the restrictive requirements" of the commodity musical (paragraph 5).

Which change in a property of pilin will be observed after modification by PptB? A. Increase in number of disulfide bonds B. Decrease in molecular weight C. Increase in enzymatic activity D. Decrease in isoelectric point

D. Decrease in isoelectric point, PptB is a phosphotransferase, which adds a phosphoglycerol to pilin subunits. The addition of this group (phosphoglycerol) adds a negative charge to pilin and thus decreases its isoelectric point.

Suppose a blood sample tested above the range (6.0 mg/dL) of the standards used in the experiment. What modification will provide a more precise reading by data interpolation as opposed to extrapolation using the same standards? A. Increase the enzyme concentration. B. Increase the oxygen pressure. C. Decrease the content of oxygen acceptor. D. Dilute the sample with additional solvent.

D. Dilute the sample with additional solvent., adding solvent, the concentration of glucose will be lowered, and the resulting absorbance will fall within the range of the standards

WRONG: Based on the first paragraph, which of the following statements best summarizes Stendhal's view of fiction? A. Fiction should reveal the author's inner feelings. B. Fiction should reorder life's events in a pleasing manner. C. Fiction should illustrate life's important ideas. D. Fiction should strive to duplicate life's events.

D. Fiction should strive to duplicate life's events., Stendhal saw fiction as "the mirror in the roadway" (first paragraph) and comments that "one mirror is like another, a mechanical reflector." This view certainly implies that fiction should seek to duplicate life's events

Which of the following comparisons is consistent with the opinions expressed by the author of this passage? A. Shakespeare was a much better writer than Hemingway. B. Faulkner's fiction is much more personal than Hemingway's fiction. C. Hemingway's fiction has a wide variety of characters. D. Hemingway's fiction is more clearly personal than Faulkner's fiction.

D. Hemingway's fiction is more clearly personal than Faulkner's fiction., the passage states "You could no more reconstruct Faulkner's life or personality from his fiction than you could reconstruct Shakespeare from his plays" (paragraph 3).

According to the passage, access to health care in the United States depends on which of the following? The individual's demonstrated need for health care Whether the individual has access to health insurance The proximity of healthcare professionals to the individual A. I only B. II only C. I and III only D. II and III only

D. II and III only, [having limited access to health care] stems from two aspects of the U.S. healthcare system: the many Americans without health insurance and the tendency of healthcare professionals to locate and practice in relatively affluent urban and suburban areas."

The setting of the Broadway musical West Side Story, an adaptation of Shakespeare's play Romeo and Juliet, is drastically different from the Shakespearean play. What is the relevance of this to the passage? A. It supports a claim about commodity musicals. B. It challenges a claim about Broadway musicals and adaptations. C. It challenges a claim about the titles of commodity musicals. D. It supports a claim about Broadway musicals that are not commodity musicals.

D. It supports a claim about Broadway musicals that are not commodity musicals., "These [non-commodity Broadway] musicals were usually given brand-new titles, to emphasize their originality" (first paragraph). They were not simply attempts to replicate or recall a commercially successful predecessor.

How would the passage argument be affected if it were demonstrated that most Americans are interested in the fine art now being produced? A. Its analogy between art and a recession would be false. B. Its wish for real critical debate would be encouraged. C. Its discouraging conclusion would not be justified. D. Its disparaging remarks would apply to more people.

D. Its disparaging remarks would apply to more people., Were "most" Americans interested in art, this concern with being part of the "majority" would be less salient, but an interest in belonging to a "select" group is ultimately less central to the author's argument than is the general fear among those interested in art of overlooking genius.

WRONG: Which of the following findings would most weaken the Mexican hypothesis as presented in the passage? A. An abundance of leisure time is not correlated with an abundance of fine-quality artifacts. B. Pottery from ancient Mexico is stylistically similar to Native American pottery found in the Woodlands. C. There is evidence that emigration took place about 1200 BC from the area that is now Mexico to western areas of the U.S. D. Leisure time tends to decrease when a people switches to farming from hunting and gathering.

D. Leisure time tends to decrease when a people switches to farming from hunting and gathering., If, however, leisure time decreases with the advent of agriculture, then it would no longer follow that Mexican farmers were likely to have had the time to devote to the building of the mounds, which would of course weaken the hypothesis

Based on the information in the passage, which immune cells would mount the initial immune response to N. meningitidis that results in meningitis? A. B cells B. Cytotoxic T cells C. Helper T cells D. Microglia

D. Microglia, Microglia are phagocytotic innate immune cells specific to the brain. The other cells are adaptive immune system cells and require activation by microglia in order to mount an immune response.

The ionic form of which metal atom is NOT likely to be found in the pocket of a catalytically active DNA polymerase? A. Zn B. Fe C. Mg D. Na

D. Na, Sodium does not readily form a divalent cation, essential for DNA polymerase catalytic activity

Which process is most likely responsible for the failure of a gamete to receive a copy of a particular chromosome? A. Recombination B. Linkage C. X inactivation D. Non-disjunction

D. Non-disjunction, occurs when sister chromatids fail to separate during cell division.

Which of the following reasons best explains why it is possible to separate a 1:1 mixture of 1-chlorobutane and 1-butanol by fractional distillation? A. Both 1-chlorobutane and 1-butanol are polar. B. Both 1-chlorobutane and 1-butanol are nonpolar. C. The boiling point of 1-chlorobutane is substantially higher than that of 1-butanol. D. The boiling point of 1-chlorobutane is substantially lower than that of 1-butanol.

D. The boiling point of 1-chlorobutane is substantially lower than that of 1-butanol., The molecules have similar molecular weights, but 1-butanol has a hydroxyl functional group that can participate in hydrogen bonding. Hydrogen bonding is a particularly strong force of intermolecular attraction, making its boiling point higher

The presence of which type of intercellular connections between endothelial cells of brain capillaries results in the blood-brain barrier? A. Desmosomes B. Gap junctions C. Intercalated discs D. Tight junctions

D. Tight junctions, intercellular junctions that prevent the movement of solutes within the space between adjacent cells. In blood capillaries, neighboring endothelial cells form tight junctions with one another to restrict the diffusion of harmful substances and large molecules into the interstitial fluid surrounding the brain.

Which of the following policy suggestions demonstrates acceptance of one or more of Talley's claims, as they are described in the passage? A. An increase in the number of total slots available at urban medical schools B. Classification of all family medicine as primary care medicine C. Travel subsidies for urban physicians interested in providing health care to rural Americans D. Tuition subsidies for people from rural areas who apply to medical schools

D. Tuition subsidies for people from rural areas who apply to medical schools, "students with rural origins are more likely to train in primary care and return to rural areas," suggests that if there were more students from rural areas in medical school, there would ultimately be more health care professionals in rural areas.

In Drosophila, white eyes are recessive to red eyes, and yellow bodies are recessive to dark bodies; both genes are on the X chromosome. The genotype of a red-eyed, dark-bodied female (XX) could be determined by mating it with a male (XY) that has which of the following phenotypes? A. Red eyes, dark body B. Red eyes, yellow body C. White eyes, dark body D. White eyes, yellow body

D. White eyes, yellow body, The female is red-eyed and dark bodied, which means she has a dominant phenotype. However, the female could also be homozygous or heterozygous for one or both traits. Mating this type of female with a male with a recessive phenotype for both traits (white eyes and yellow body) would determine the genotype of the female.

Assume that a study is performed in which only the physiological aspects of emotion are chemically suppressed and that the participants are then placed in a situation that would normally anger them. The passage author would presumably expect the participants to experience: A. an abnormally intense disapproval of the situation. B. an apparently normal response to the situation. C. indifference and inattention to the situation. D. a calm negative assessment of the situation.

D. a calm negative assessment of the situation., "emotion requires at least two components: measurable physiological events and a belief or thought about some person or situation, real or imagined" (paragraph 4). If the physiological element of the emotion were withdrawn from the experience, but an event likely to incite anger was still present, then the participants would be without the "agitation" the author describes as associated with anger in paragraph 2.

The use of pulsed laser radiation in the PRK procedure, as opposed to continuous laser radiation, allows the cornea to: A. absorb more radiation. B. change its index of refraction. C. increase the area exposed to radiation. D. maintain a lower average temperature.

D. maintain a lower average temperature, pulsed laser radiation interacts with the cornea for a shorter time than a continuous laser radiation, thus less heat is transferred to the cornea. This allows the cornea to maintain a lower average temperature by cooling off between pulses.

Based on the passage, what can be determined about the composition of the mRNA that encodes the protein from which ghrelin is cleaved? It is composed of: A. more than 28 amino acids. B. exactly 84 nucleotides. C. exactly 87 nucleotides. D. more than 87 nucleotides.

D. more than 87 nucleotides., Each amino acid is coded by 3 nucleotides; thus, 84 nucleotides are needed to code for the 28-amino-acid peptide ghrelin. To this number, the triplet that codes for the STOP codon needs to be added. Therefore, 87 is the minimum number of nucleotides for the 28-amino-acid peptide ghrelin. passage indicates that ghrelin is cleaved from a longer peptide chain.-so the total number of nucleotides is higher than 87.

If methane (CH4) were substituted for NH3 in the aluminum can, the crushing of the can would: A. occur because CH4, being polar, would dissolve in the water in the tray. B. occur because CH4, being nonpolar, would dissolve in the water in the tray. C. not occur because CH4, being polar, would not dissolve in the water in the tray. D. not occur because CH4, being nonpolar, would not dissolve in the water in the tray.

D. not occur because CH4, being nonpolar, would not dissolve in the water in the tray., CH4 is a nonpolar molecule and will not dissolve appreciably in water. Since the CH4 will remain in the gas phase, the can will not be crushed by the formation of a vacuum inside the can.​

WRONG Based on the passage, the author feels that his readers are generally: A. very understanding of the mistakes he makes in his work. B. unconcerned with how they are being manipulated by him. C. confused by the way that he imposes order on chaos. D. quick to assume that he is writing from his own experiences.

D. quick to assume that he is writing from his own experiences. "I' character speaks in one of my novels or stories he is to be read as me, sneakily expressing my attitudes and feelings from behind a mask" (paragraph 2).

According to the passage, the key distinction between what most people think of as a small-world experience and Watt's mathematical model of small worlds is that the mathematical model: A. limits the number of possible targets. B. relies on the cooperation of participants. C. cannot take sociable people into account. D. selects targets randomly.

D. selects targets randomly., "There is a...difference between what most people mean by a small-world experience and what mathematicians mean. The chances of meeting a person who knows someone from one's past are not the same as the chances of connection between two people taken at random" (paragraph 8)

Assume that a mutant allele is the result of the deletion of two entire codons. The base pair length of the mutant allele, compared to that of the wild-type allele, would have: A. two fewer nucleotides. B. three fewer nucleotides. C. four fewer nucleotides. D. six fewer nucleotides.

D. six fewer nucleotides.

WRONG The author's attitude toward commodity musicals is one of: A. enthusiastic endorsement. B. grudging admiration. C. contingent disappointment. D. strong disapproval.

D. strong disapproval., calls commodity musicals "inoffensively entertaining at best, numbingly tedious at worst" (paragraph 2). Further, the author complains, they are "a watered-down, parasitical imitation of the real thing" (final paragraph). Thus, the author clearly expresses "strong disapproval."

Binding of erythromycin to the large subunit of the bacterial ribosome most likely blocks the transfer of the tRNA bound at: A. the E site to the P site of the ribosome. B. the P site to the A site of the ribosome. C. the E site to the A site of the ribosome. D. the A site to the P site of the ribosome.

D. the A site to the P site of the ribosome., During protein translation, aminoacyl transferase functions to transfer the tRNA originally bound at the A (amino acid) site to the P (peptide) site and later to the E (exit) site of the ribosome. This option follows this order of transfer

What could be interpreted as a paradoxical aspect of Spencer's behavior was his: A. obvious affluence, despite an explicit disdain for wealth. B. fervent belief in capitalism, despite evolutionary evidence against its merits. C. apparent sense of inferiority, despite glowing praise from his followers. D. voluntary public appearance, despite an aversion to social excitement.

D. voluntary public appearance, despite an aversion to social excitement. Spencer that he "detested public speaking"; moreover, "he had come to the U.S. to reinvigorate his 'greatly disordered nervous system,' and he withstood all inducements to what he called 'social excitement'" (paragraph 2).

On the day of the experiment, the subjects drank about 1 L of water on average and excreted about 400 mL of urine. The most likely explanation for the difference between water intake and urine excretion is that: A. the extra water was stored as blood. B. water was consumed with the food that was eaten. C. the extra water was excreted by the intestine. D. water was excreted via the skin and the lungs.

D. water was excreted via the skin and the lungs., Extra water is normally excreted through skin and lungs.

prepatory phase of glycolysis

Endergonic, Glucose splits into PGAL (G3P), Two ATP molecules are consumed in the preparatory phase during two phosphorylation events. The first reaction converts glucose to glucose-6-phosphate, and the second reaction converts fructose-6-phosphate to fructose 1,6-biphosphate.

Isoelectric focusing

Isoelectric focusing allows separation of the molecules based on their isoelectric point.

During Reaction 2, did the oxidation state of N change? A. Yes; it changed from -3 to -4. B. Yes; it changed from 0 to +1. C. No; it remained at -3. D. No; it remained at +1.

Missed, C. No; it remained at -3., involves nitrogen is the protonation of ammonia (NH3 + H+ → NH4+). Acid-base reactions do not involve oxidation state changes. The oxidation state of N in NH3 is -3. Each H is +1 and is balanced by the -3 of N to make a neutral compound. The oxidation state of N does not change when the N is protonated

Native PAGE

Native PAGE is used to separate molecules based on their electrophoretic mobility, relying on length, conformation, and charge

Diffraction

Occurs when an object causes a wave to change direction and bend around it

payoff phase of glycolysis

Oxidative conversion of glyceraldehyde 3-phosphate to 4 ATP, 2 NADH, and 2 pyruvate molecules In the payoff phase, four ATP molecules are produced. The first two ATP molecules are produced in the conversion of 1,3-bisphosphoglycerate to 3-phosphoglycerate, and another two ATP molecules are produced in the conversion of phosphoenolpyruvate to pyruvate.​

Amine

R-NH2, compounds and functional groups that contain a basic nitrogen atom with a lone pair

product inhibition

Situation in which the product of a reaction inhibits the activity of the enzyme that produces it

Refraction

The bending of a wave as it passes at an angle from one medium to another

Reflection

The bouncing back of a wave when it hits a surface through which it cannot pass.

double displacement substrate binding

aka ping pong, binding of the first substrate causes the enzyme to change into an intermediate form that will bind the second substrate.

dipole-dipole forces

attractions between oppositely charged regions of polar molecules

Ping-Pong Substrate Binding

binding of the first substrate causes the enzyme to change into an intermediate form that will bind the second substrate.

competitive inhibitor

competes with substrate for active site

Cytotoxic T cells

destroy pathogens and release chemicals called cytokines

random order substrate binding

either substrate could bind first

Amide

functional groups in which a carbonyl carbon atom is linked by a single bond to a nitrogen atom and either a hydrogen or a carbon atom.

One company sells a defibrillator for home use that uses a 9-volt DC battery. The battery is rated at 4.2 A•hr (amp•hour). Roughly how much charge can the battery deliver? A. 4.2 C B. 38 C C. 15,000 C D. 136,000 C

guessed C. 15,000 C, current is flow of charge per unit time. Thus, charge equals current multiplied by time, hence 4.2 A × 1 hr = 4.2 A × 3600 s = 15,120 C ≈ 15,000 C.

mixed inhibition

inhibitor binds to allosteric site in either enzyme or enzyme-substrate complex vmax decreases If inhibitor binds to enzyme, it increases Km (lowers affinity) If inhibitor binds to enzyme-substrate complex, it lowers Km (increases affinity

ACC1

is a carboxylase and will convert acetyl-CoA to malonyl-CoA through the addition of a carboxyl group to acetyl-CoA.

ion exchange chromatography

molecules separated based on net surface charge

X inactivation

occurs when one X chromosome in a female becomes almost completely inactivated during embryonic development

ordered substrate binding

one substrate must bind the enzyme before the second substrate is able to bind

gap junctions

provide cytoplasmic channels between adjacent animal cells

intercalated discs

specialized connections between myocardial cells containing gap junctions and desmosomes

adaptive immunity

the ability to recognize and remember specific antigens and mount an attack on them, antigen-specific immune response

London dispersion forces

the intermolecular attraction resulting from the uneven distribution of electrons and the creation of temporary dipoles

Polarization

transverse wave, the direction of the oscillation is perpendicular to the direction of motion of the wave.