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Chapter 23. Toxic Effects of Metals
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Which of the following is NOT a major excretory pathway of metals?
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a. are responsible for metal transport in the bloodstream.
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b. are involved in the biotransformation of metals.
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c. invoke hypersensitivity reactions.
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d. provide high-affinity binding of copper and mercury.
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e. are involved in extracellular transport of metals.
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Which of the following metal-binding proteins is NOT correctly paired with the metal it binds?
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c. metallothioneins—zinc.
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e. albumin—nonspecific metal binding.
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Which of the following groups is LEAST likely to chelate metals?
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What is the mechanism of toxicity of arsenic (As)?
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a. inhibition of mitochondrial respiration.
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b. impairment of calcium uptake by membrane transporters.
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c. accumulation in renal corpuscle.
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d. abolition of sodium–potassium gradient.
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e. destruction of surfactant in the lungs.
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Lead’s toxicity is largely due to its ability to mimic and interfere with normal functioning of which of the following ions?
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Which of the following statements regarding mercury (Hg) toxicity is FALSE?
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a. A major source of environmental mercury is rainwater.
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b. Mercury vapor is much more dangerous than liquid mercury.
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c. Mercury vapor inhalation is characterized by fatigue and bradycardia.
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d. Microorganisms in bodies of water can convert mercury vapor to methylmercury.
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