Nursing Elites

1. What is a mutation?

• A. A change in the DNA sequence
• B. A type of protein
• C. A normal part of the DNA replication process
• D. A harmless variation in DNA

Correct answer: A

Rationale: A mutation is defined as a change in the DNA sequence, which can occur due to various factors such as errors during DNA replication, exposure to mutagens (e.g., chemicals, radiation), or spontaneous changes. These alterations can lead to modifications in the genetic information carried by an organism, resulting in effects that can range from harmless variations to causing genetic disorders or diseases. Mutations play a crucial role in genetic diversity and evolution. Choices B, C, and D are incorrect as they do not accurately define what a mutation is. Option B is incorrect because mutations are not a type of protein but rather changes in DNA. Option C is incorrect because while mutations can occur during DNA replication, they are not considered a 'normal' part of the process as they can lead to genetic variations. Option D is incorrect because mutations can have a wide range of effects and are not always harmless variations.

2. When is a solution formed?

• A. One substance dissolves in another
• B. Two or more substances react chemically
• C. A solid changes to a liquid
• D. None of the above

Correct answer: A

Rationale: A solution is formed when one substance dissolves in another. This process creates a homogeneous mixture where the solute is dispersed in the solvent, resulting in a uniform composition throughout the mixture. Choice B is incorrect because chemical reactions involve the transformation of substances into new compounds, not the formation of solutions. Choice C is incorrect as it describes a physical change from a solid to a liquid, not the formation of a solution. Choice D is incorrect as one substance dissolving in another is the defining characteristic of a solution.

3. What happens to the frequency of a wave when its wavelength is doubled, assuming the speed remains constant?

• A. Frequency remains the same.
• B. Frequency is halved.
• C. Frequency is doubled.
• D. Frequency information is insufficient to determine.

Correct answer: B

Rationale: When the wavelength of a wave is doubled, and the speed of the wave remains constant, the frequency of the wave is halved. This relationship is governed by the equation speed = frequency x wavelength. Therefore, if the wavelength is doubled while the speed remains constant, the frequency must be halved to maintain a constant speed. Choice A is incorrect because frequency and wavelength are inversely proportional when speed is constant. Choice C is incorrect as doubling the wavelength does not result in a doubled frequency. Choice D is incorrect as the relationship between frequency, wavelength, and speed can be determined using the given information.

4. Which hormone, produced by the adrenal glands, is essential for regulating electrolyte balance, particularly sodium and potassium, in the body?

• A. Aldosterone
• B. Epinephrine
• C. Cortisol
• D. Insulin

Correct answer: A

Rationale: Aldosterone is a hormone produced by the adrenal glands that plays a crucial role in maintaining electrolyte balance, specifically by regulating sodium and potassium levels in the body. Its primary function involves acting on the kidneys to increase the reabsorption of sodium and water while promoting the excretion of potassium. This process is essential for regulating blood pressure, fluid balance, and electrolyte concentrations in the body. Epinephrine is associated with the fight or flight response, cortisol is a stress hormone, and insulin is responsible for regulating blood sugar levels as produced by the pancreas. Therefore, the correct answer is Aldosterone as it directly targets electrolyte balance, particularly sodium and potassium, in the body.

5. Which of the following correctly lists the four properties that all types of muscle tissue share?

• A. Contractile, excitable, elastic, extensible
• B. Contractile, voluntary, elastic, extensible
• C. Contractile, excitable, voluntary, extensible
• D. Contractile, excitable, elastic, voluntary

Correct answer: A

Rationale: The correct answer is A: 'Contractile, excitable, elastic, extensible.' All types of muscle tissue share these four properties. Muscle tissue can contract, respond to stimuli, stretch and return to its original shape (elastic), and extend or stretch (extensible). Choice B is incorrect because not all muscle tissues are voluntary (some are involuntary). Choice C is incorrect because not all muscle tissues are voluntary. Choice D is incorrect because not all muscle tissues are voluntary and lack the elastic property.

Similar Questions