Nursing Elites

1. What phenomenon is responsible for the mirage effect seen in deserts?

• A. Diffraction
• B. Refraction
• C. Interference
• D. Polarization

Correct answer: B

Rationale: Refraction is the bending of light as it passes from one medium to another of different density. In deserts, the temperature gradient causes light to bend, creating the mirage effect where distant objects appear distorted or displaced. Diffraction refers to the bending of light around obstacles or apertures, not the cause of mirages. Interference involves the superposition of two or more waves, which is not the mechanism behind mirages. Polarization refers to the orientation of light waves in a specific plane and is not responsible for the mirage effect in deserts. Therefore, the correct answer is refraction.

2. Which element is used in fluorescent lamps and emits ultraviolet light when excited?

• A. Mercury
• B. Neon
• C. Argon
• D. Krypton

Correct answer: A

Rationale: Mercury is the correct element used in fluorescent lamps to emit ultraviolet light when excited. When an electric current passes through the mercury vapor inside the lamp, it generates ultraviolet (UV) light. This UV light then excites the phosphors coated on the inner surface of the lamp, causing them to emit visible light. Neon, argon, and krypton are not commonly used in fluorescent lamps for this purpose. Neon is primarily used in neon signs, argon is used in incandescent and fluorescent bulbs for inertia gas, and krypton is mainly used in certain types of specialized light bulbs for its specific properties.

3. Which of the following describes the flow of genetic information from DNA to protein?

• A. Replication
• B. Transcription
• C. Translation
• D. Both transcription and translation

Correct answer: D

Rationale: The correct answer is D, 'Both transcription and translation.' Genetic information flows from DNA to RNA through transcription and from RNA to protein through translation. Replication is the process of copying DNA to produce an identical DNA molecule. Choice A, 'Replication,' is incorrect because replication is not directly involved in the flow of genetic information from DNA to protein. Choice B, 'Transcription,' is incorrect as it represents the process of synthesizing RNA from a DNA template, which is the initial step in the flow of genetic information. Choice C, 'Translation,' is also incorrect as it refers to the process of translating the information in mRNA into a sequence of amino acids during protein synthesis, which is the second step in the flow of genetic information.

4. Enzymes are ________ molecules that serve as _______ for certain biological reactions.

• A. Enzymes are irrelevant molecules that serve as suppressors for certain biological reactions.
• B. Enzymes are acidic molecules that serve as catalysts for certain biological reactions.
• C. Enzymes are lipid molecules that serve as catalysts for certain biological reactions.
• D. Enzymes are protein molecules that serve as catalysts for certain biological reactions.

Correct answer: D

Rationale: Enzymes are protein molecules that serve as catalysts for certain biological reactions. Enzymes are biological molecules that speed up chemical reactions in living organisms by lowering the activation energy required for the reactions to occur. They are typically proteins that have specific shapes and active sites that allow them to interact with specific substrates and facilitate reactions without being consumed themselves. The other choices are incorrect because enzymes are not irrelevant, acidic, or lipid molecules; they are primarily proteins known for their catalytic properties.

5. Which of the following are the products of anaerobic respiration in humans?

• A. Ethyl alcohol and CO2
• B. Ethyl alcohol only
• C. Lactic acid and CO2
• D. Lactic acid only

Correct answer: C

Rationale: During anaerobic respiration in humans, lactic acid and CO2 are produced. Choice A, 'Ethyl alcohol and CO2,' is incorrect because ethyl alcohol is not a product of anaerobic respiration in humans. Choice B, 'Ethyl alcohol only,' is incorrect as ethyl alcohol is not a product of anaerobic respiration in humans. Choice D, 'Lactic acid only,' is incorrect because CO2 is also a product of anaerobic respiration in humans.

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