Nursing Elites

1. A spring with a spring constant of 100 N/m is stretched 0.2 m from its equilibrium position. What is the potential energy stored in the spring?

• A. 2 J
• B. 4 J
• C. 8 J
• D. 20 J

Correct answer: C

Rationale: The potential energy stored in a spring is given by the formula \(PE = \frac{1}{2}kx^2\), where \(k\) is the spring constant and \(x\) is the displacement from the equilibrium position. Substituting the given values, we get \(PE = \frac{1}{2} \times 100 \times (0.2)^2 = 8\) J.

2. What is the name of the regulatory region in a gene that controls its expression?

• A. Exon
• B. Intron
• C. Promoter
• D. Enhancer

Correct answer: C

Rationale: A) Exon: Exons are the coding regions of a gene that are transcribed into mRNA and eventually translated into proteins. Exons do not regulate gene expression. B) Intron: Introns are non-coding regions of a gene that are removed during RNA processing and do not play a direct role in controlling gene expression. C) Promoter: The promoter is a regulatory region located at the beginning of a gene that initiates the process of transcription by binding transcription factors and RNA polymerase. It plays a crucial role in controlling gene expression. D) Enhancer: Enhancers are regulatory regions that can be located far from the gene they regulate and can increase the transcription of a gene. While enhancers are important for gene expression, the specific region that controls gene expression is the promoter. Therefore, the correct answer is C) Promoter, as it is the regulatory region in a gene that controls its expression by initiating transcription.

3. What is the process by which one element changes into another through radioactive decay known as?

• A. Transmutation
• B. Fission
• C. Fusion
• D. Oxidation

Correct answer: A

Rationale: The correct answer is A: Transmutation. Transmutation is the correct term to describe the process by which one element changes into another element through radioactive decay. In transmutation, the atomic structure of the element is altered, leading to a change in the element's identity. Choice B, Fission, refers to the splitting of a heavy nucleus into lighter nuclei. Choice C, Fusion, involves the merging of lighter nuclei to form a heavier nucleus. Choice D, Oxidation, is not related to the process of one element changing into another through radioactive decay.

4. What does the T wave on an ECG correspond to?

• A. Atrial depolarization
• B. Ventricular depolarization
• C. Atrial repolarization
• D. Ventricular repolarization

Correct answer: D

Rationale: The T wave on an ECG corresponds to ventricular repolarization. Following ventricular depolarization, which is represented by the QRS complex, the ventricles undergo repolarization during the T wave. This phase signifies the recovery of ventricular muscle cells as they prepare for the subsequent depolarization cycle. Choices A, B, and C are incorrect because the T wave specifically reflects the repolarization of the ventricles, not the atria or their respective depolarization or repolarization phases.

5. Which part of the brain is responsible for regulating heart rate, breathing, and swallowing?

• A. Cerebrum
• B. Cerebellum
• C. Medulla oblongata
• D. Thalamus

Correct answer: C

Rationale: The correct answer is C, the medulla oblongata. This part of the brain, located at the base of the brainstem, is primarily responsible for regulating essential functions like heart rate, breathing, and swallowing. Choices A, B, and D are incorrect. The cerebrum is associated with higher brain functions such as thinking and voluntary movements, the cerebellum controls coordination and balance, and the thalamus serves as a relay station for sensory information. Therefore, the medulla oblongata specifically governs the autonomic functions critical for survival.

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