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This passage is from George Graham Vest’s speech Tribute to Dogs:
Gentlemen of the Jury: The best friend a man has in the world may turn against him and become his enemy. His son or daughter that he has reared with loving care may prove ungrateful. Those who are nearest and dearest to us, those whom we trust with our happiness and our good name may become traitors to their faith. The money that a man has, he may lose. It flies away from him, perhaps when he needs it most. A 5 man's reputation may be sacrificed in a moment of ill-considered action. The people who are prone to fall on their knees to do us honor when success is with us, may be the first to throw the stone of malice when failure settles its cloud upon our heads. The one absolutely unselfish friend that man can have in this selfish world, the one 10 that never deserts him, the one that never proves ungrateful or treacherous is his dog. A man's dog stands by him in prosperity and in poverty, in health and in sickness. He will sleep on the cold ground, where the wintry winds blow and the snow drives fiercely, if only he may be near his master's side. He will kiss the hand that has no food to offer. He will lick the wounds and sores that come in encounters with the 15 roughness of the world. He guards the sleep of his pauper master as if he were a prince. When all other friends desert, he remains. When riches take wings, and reputation falls to pieces, he is as constant in his love as the sun in its journey through the heavens.
If fortune drives the master forth, an outcast in the world, friendless and homeless, 20 the faithful dog asks no higher privilege than that of accompanying him, to guard him against danger, to fight against his enemies. And when the last scene of all comes, and death takes his master in its embrace and his body is laid away in the cold ground, no matter if all other friends pursue their way, there by the graveside will the noble dog be found, his head between his paws, his eyes sad, but open in alert 25 watchfulness, faithful and true even in death.
Robert Frost’s The Road Not Taken Two roads diverged in a yellow wood, And sorry I could not travel both And be one traveler, long I stood And looked down one as far as I could To where it bent in the undergrowth; 5 Then took the other, as just as fair, And having perhaps the better claim, Because it was grassy and wanted wear; Though as for that the passing there 10 Had worn them really about the same, And both that morning equally lay In leaves no step had trodden black. Oh, I kept the first for another day! 15 Yet knowing how way leads on to way, I doubted if I should ever come back. I shall be telling this with a sigh Somewhere ages and ages hence: 20 Two roads diverged in a wood, and I- I took the one less traveled by, And that has made all the difference.
2 Production of thyroid hormones by the thyroid gland is negatively influenced by? A TRH. B TSH. C FSH. D T4.
3 If a person has the thyroid gland completely removed and does not take any thyroid hormone pills, the above pathway would be affected by? A Increased conversion of T4 to T3 in the peripheral system. B Decrease in TSH level. C Increase in TRH level . D No change in BMR.
4 A hypoactive thyroid gland does not make enough thyroid hormone for the body’s
needs and metabolism despite proper stimulation. This results in a slow metabolism. A person with a hypoactive thyroid has blood drawn to measure the thyroid hormone levels. Which of the following are likely from this person? A Low T4, Low T3, High TSH. B High T4, Low T3, High TSH. C Normal T4, Normal T3, Low TSH. D High T4, High T3, Low TSH.
5 A hyperactive thyroid gland makes too much thyroid hormone creates a very high metabolism. A thyroid gland can be overactive without stimulation from the pituitary or hypothalamus (automaticity). A person with a hyperactive thyroid gland has blood drawn to measure thyroid hormone levels. Which of the following are likely from this person? A Low T4, Low T3, High TSH. B High T4, Low T3, High TSH. C Normal T4, Normal T3, Low TSH. D High T4, High T3, Low TSH.
6 Occasionally people abuse medications and take thyroid hormone pills unnecessarily. Sometimes they do this thinking it will help with weight loss by boosting the metabolism. If a person was taking excessive thyroid hormone pills and had blood drawn to measure thyroid hormone levels; which of the following would likely be from this person?
A Low T4, Low T3, High TSH. B High T4, Normal T3, Low TSH. C Normal T4, Normal T3, Low TSH. D High T4, High T3, Low TSH.
Unit Two Questions 7 – 11 In 1889, Svante Arrhenius proposed that the rate constant for a given reaction is given by the formula:
k=Ae(Ea /RT) where Eo is the activation energy for the reaction, R is the gas constant (8.314 J/mol K), T is the absolute temperature, and A is a factor, which depends on factors such as molecular size. Catalysts change the reaction pathway, which may result in a change in Ea, A, or both. In heterogeneous catalysis, the catalyst is in a different phase from the reactants and products. For example, a solid may catalyse a fluid-phase reaction. Such catalysis involves the following steps:
• A reactant molecule diffuses through the liquid to the surface of the catalyst.
• The reactant molecule bonds to the catalyst (adsorption).
• Adsorbed molecules bond with each other or with a molecule which collides with the adsorbed molecules.
• The product leaves the catalyst.
In homogeneous catalysis, the catalyst is in the same phase as the reactants and products. Acids often act by this mechanism.
7 The rate of a reaction may depend on which of the following?
I. Concentrations of the reactants II. Concentration of a catalyst III. Surface area of a heterogeneous catalyst IV. Temperature
A I only
B IV only C I and IV only D I, II, III, and IV
8 Which of the following is true of a catalysed reaction?
A a catalyst may be the limiting reagent. B at equilibrium, more products are produced when a catalyst is present. C the catalysed reaction pathway has a lower energy of activation than the uncatalysed
reaction pathway. D the rate of the reverse reaction will be slower for the catalysed reaction.
9 Consider a reversible reaction. If the activation energy for the forward reaction is lowered by a catalyst, what can be said about the activation energy for the reverse reaction? A it is also lowered. B it is raised. C it is unaffected by the catalyst. D the effect of the catalyst on the reverse reaction cannot be predicted without more
information.
10 If the solid line in the graph below represents the reaction profile for an uncatalysed reaction, which line might represent the reaction profile for the catalysed reaction?
A line A. B line B. C line C. D line D.
11 Suppose a reaction is acid-catalysed by a solution of pH 3.0. What can be said about the
pH of the resulting solution? A it will be greater than 3.0 because the acid is consumed. B it will be equal to 3.0 because the acid is regenerated. C it will be equal to 3.0 because catalysts have no effect on equilibrium. D it cannot be predicted without information on the acidity of the reactants and
Unit Four Questions 16-19 The human body may operate as a conductor it completes an electrical circuit. When this occurs the person may experience an electric shock. The severity of the shock increases as both the magnitudes of the current and the contact time increase. Different types of tissues have different conductivities: current passing through electrically excitable tissue like muscle and nerves inflicts the most pain and damage. A current between 1 and 10 mA may be perceived as painful, although it is usually harmless to a healthy individual. However, once current in excess of 10 mA passes through muscle tissue, the damage inflicted may be more severe, especially if the electrocution is caused by the person grasping a live wire, which they may not be able to release. Surprisingly, currents passing through cardiac tissue pose less of a threat if the magnitude of the current exceeds 1000 mA than if the magnitude were 70 mA. A lower current disrupts the electrical coupling of the heart, causing irregular contraction, or ventricular fibrillation. A current over 1 A passing through cardiac tissue is so large that it causes the heart to stop completely; once the current is removed, the heart usually regains its normal rhythm. Ohm’s law implies the resistance of the body influences the severity of damage resulting from a shock. Human tissue has relatively low electrical resistivity since there is an abundance of dissolved ions in the cells. However, the waterproof outer layer of skin on the body has a high resistance when dry; approximately 104 Ω. This resistance significantly decreases when the skin is moistened. The total electrical resistance of the body can be approximated by using the electrical resistance of the skin.
16 A labourer (with dry skin) accidentally comes into contact with a live wire and experiences a current of 1 A. The resistance of the wire is 9 Ω. Remembering that power is the product of current and voltage, how much total energy is dissipated after 45 seconds? A 15 J. B 675 J. C 10 kJ. D 451 kJ.
17 What impact would a high cellular ion concentration have if a person was to experience electrocution? A they would be more resistant to damage. B they would be less resistant to damage. C their resistance to damage would not be changed. D insufficient information is provided to answer the question.
18 A defibrillator is a device used to momentarily stop then restart heart activity. What is the minimum voltage needed between the leads of the defibrillator in order for it to be effective against dry skin? A 7 V. B 102 V. C 7 x 102 V. D 104 V.
19 A person with dry skin accidentally touches a live wire. The wire has a current of 1.5A, with resistance of only 1Ω. A friend, just coming out of the shower, tries to assist the person but makes skin direct contact with them. The time needed for 10 Coulomb’s if charge to pass through the entire circuit will? A increase. B decrease. C remain the same. D insufficient information is provided to answer the question.
Unit Five Question 20 A block of mass m starts from rest and slides down a frictionless semi-circular track from a height h as shown below. When it reaches the lowest point of the track, it collides with a stationary piece of putty also having mass m.
20 If the block and the putty stick together and continue to slide, the maximum height that the block-putty system could reach is: A h/4.
Morphine alkaloids derived from the opium poppy have long been used as analgesics. Codeine, the methyl ether of morphine, is a naturally occurring alkaloid with medicinal properties very similar to those of morphine. Thousands of derivatives of morphine have been synthesized and tested for their biological effects. For example, the diacylated derivative of morphine, heroin, is a highly addictive drug. Much effort has gone into understanding how morphine and its derivatives function.
Figure 1 Studies have shown that certain common structural features of alkaloids are required for the compound to exhibit biological activity. These structural requirements are summarized by the so called “morphine rule”: 1. an aromatic ring adjacent to a quaternary carbon; 2. two carbons between this quaternary carbon and a tertiary amine. Demerol and methadone, shown in Figure 2, are two synthetic alkaloids designed to satisfy the “morphine rule.” Synthetic alkaloids such as these have been found to mimic certain physiological properties of morphine and its derivatives, and have found pharmacological application due to other, more desirable biological effects. Methadone has been used widely as a treatment for heroin addiction; it reduces the physical symptoms accompanying withdrawal without producing many of the other effects of heroin.
21 How many chiral carbons are there in morphine? A 4. B 5. C 6. D 7.
22 Morphine can be reacted with 2 equivalents of ethanoyl chloride (acetyl chloride) to form heroin. In this reaction, the hydroxy groups of morphine function as: A nucleophiles. B electrophiles. C leaving groups. D lewis acids.
23 Which of the following compounds would be most likely to have morphine-like biological effects?
24 One of the requirements of the “morphine rule” is that an aromatic ring be attached to a quaternary carbon in order for the molecule to be biologically active. The quaternary carbon of any morphine-like substance must be:
I. a stereocenter II. sp3 hybridized III. sp2 hybridized
A I only. B II only. C I and II only. D I and III only.
25 Hofmann elimination involves methylation of the amine nitrogen followed by elimination (E2). Which of the following represents a possible product of one sequence of Hofmann elimination on Meperidine (demerol)?
27 During the follicular phase of a normal menstrual cycle, changes the ovary undergoes are related to pituitary secretions of A FSH. B LH. C FSH and LH. D oxytocin.
28 Common pregnancy tests rely on the detection of HCG hormone in the blood or urine. The presence of this hormone reflects: A that the corpus luteum has already involuted. B LH levels are high. C FSH is greater than LH. D endometrium stability.
29 Women who do not want to become pregnant often take birth control pills that have small amounts of progesterone or estrogen and progesterone. This is because A higher Progesterone levels prevent menstruation, inhibiting follicle development. B low Progesterone levels cause LH to spike and prevent ovulation. C ovulation requires a spike in progesterone. D the slight increase in body temperature prevents the follicle maturing.
30 Confirmatory evidence of ovulation include all of the following except: A sharp decline in estrogen levels. B peak monthly temperature. C progesterone begin to rise. D LH levels have peaked.