Nursing Elites

1. Which of the following is a characteristic of unsaturated fatty acids?

• A. They are solid at room temperature.
• B. They contain only single bonds.
• C. They have a higher melting point.
• D. They contain double or triple bonds.

Correct answer: D

Rationale: Unsaturated fatty acids contain double or triple bonds in their hydrocarbon chains. The other choices do not accurately describe unsaturated fatty acids.

2. A new invention claims to solve the energy crisis. What criteria should you use to evaluate this claim?

• A. The inventor's qualifications and credentials.
• B. The technology's cost-effectiveness and affordability.
• C. Evidence of independent testing and scientific validation.
• D. Testimonials from celebrities and public figures.

Correct answer: C

Rationale: When evaluating a claim about solving the energy crisis, it is crucial to look for evidence of independent testing and scientific validation. This ensures that the technology has been rigorously assessed and verified by experts in the field, providing credibility to the invention's effectiveness. Testimonials from celebrities and public figures (option D) may not provide reliable information about the technology's actual capabilities. The inventor's qualifications and credentials (option A) are important but do not guarantee the technology's success. Cost-effectiveness and affordability (option B) are significant factors but should be considered alongside scientific validation to assess the overall impact and feasibility of the invention.

3. The Gram stain is a differential staining technique used to classify bacteria based on their cell wall composition. Gram-positive bacteria appear

• A. Pink
• B. Blue
• C. Red
• D. Purple

Correct answer: D

Rationale: Rationale: The Gram stain is a differential staining technique that divides bacteria into two groups based on their cell wall composition: Gram-positive and Gram-negative. Gram-positive bacteria have a thick layer of peptidoglycan in their cell walls, which retains the crystal violet stain used in the Gram staining procedure. As a result, Gram-positive bacteria appear purple under the microscope after staining. In contrast, Gram-negative bacteria have a thinner peptidoglycan layer and an outer membrane that can be penetrated by the counterstain safranin, causing them to appear pink or red. Blue is not typically used to describe the color of bacteria in a Gram stain.

4. Myelin sheath is a fatty substance that insulates and protects the long extensions of some nerve cells. It is produced by:

• A. Schwann cells
• B. Astrocytes
• C. Neurons
• D. Oligodendrocytes

Correct answer: A

Rationale: The correct answer is A: Schwann cells. Schwann cells are a type of glial cell in the peripheral nervous system that produce the myelin sheath around axons. Myelin sheath is essential for the rapid conduction of nerve impulses and provides insulation and protection to nerve fibers. Astrocytes are glial cells that provide support and maintain homeostasis in the central nervous system, but they do not produce myelin. Neurons are the main functional units of the nervous system responsible for transmitting nerve impulses. Oligodendrocytes are another type of glial cell in the central nervous system that produce myelin sheath around axons in that region, not in the peripheral nervous system where Schwann cells are responsible for myelination.

5. 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 vapor in fluorescent lamps generates UV light that excites phosphors on the lamp's inner surface, producing visible light.

6. What is the process of converting DNA into a protein called?

• A. Transcription
• B. Translation
• C. Replication
• D. Mutation

Correct answer: A

Rationale: Transcription is the process of converting DNA into a molecule called messenger RNA (mRNA). This mRNA molecule carries the genetic information from DNA to the ribosomes, where it is used to make proteins.

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