Nursing Elites

1. What does half-life refer to?

• A. Radioactive intensity to completely disappear
• B. The number of neutrons in a nucleus to double
• C. The number of protons in a nucleus to change
• D. An isotope to decay by half of its initial quantity

Correct answer: D

Rationale: Half-life refers to the time it takes for half of the radioactive atoms in a sample to decay. This means that after one half-life, half of the initial quantity of the radioactive substance will have decayed. Choice A is incorrect because radioactive intensity doesn't completely disappear during half-life. Choice B is incorrect as half-life doesn't refer to the number of neutrons doubling. Choice C is incorrect as half-life doesn't relate to the number of protons changing.

2. Which of the following is used to record the measurable electrical activity of the brain?

• A. CAT scan
• B. MRI scan
• C. Electroencephalogram (EEG)
• D. X-ray

Correct answer: C

Rationale: The correct answer is an Electroencephalogram (EEG). An EEG is specifically designed to record the measurable electrical activity of the brain. It does so by using small, flat metal discs (electrodes) attached to the scalp to detect brain activity. This test is crucial in diagnosing various conditions like seizures, epilepsy, head injuries, dizziness, headaches, and brain tumors. The other options, CAT scan, MRI scan, and X-ray, are imaging techniques that do not directly measure the brain's electrical activity. CAT scan and MRI scan provide detailed images of the brain's structure, while X-ray is more suited for visualizing bone structures or dense tissues.

3. Which term describes the resistance of a substance to flow?

• A. Density
• B. Viscosity
• C. Conductivity
• D. Malleability

Correct answer: B

Rationale: Viscosity is the term used to describe the resistance of a substance to flow. It quantifies how thick or thin a fluid is and how easily it flows. Density (A) refers to the mass of a substance per unit volume and does not directly relate to resistance to flow. Conductivity (C) is the property of a material to conduct electricity or heat, not related to resistance to flow. Malleability (D) is the property of a material to be hammered or rolled into thin sheets, which is not related to resistance to flow.

4. What are the constituents of an atomic nucleus?

• A. Electrons and protons only
• B. Protons and neutrons only
• C. Electrons, protons, and neutrons
• D. None of the above

Correct answer: B

Rationale: The correct answer is B: Protons and neutrons only. Electrons are located outside the nucleus in electron shells. Protons and neutrons are the subatomic particles found within the nucleus of an atom. Protons carry a positive charge, while neutrons are neutral. These particles contribute to the mass and stability of the nucleus. Choice A is incorrect because electrons are not part of the nucleus. Choice C is incorrect as electrons are not found within the nucleus, only protons and neutrons. Choice D is incorrect as protons and neutrons are indeed constituents of an atomic nucleus.

5. What is the relationship between genetic drift and the founder effect?

• A. Founder effect is a cause of genetic drift within a small population
• B. Genetic drift is a cause of the founder effect in new populations
• C. They are the same phenomenon with different names
• D. They are unrelated concepts.

Correct answer: A

Rationale: - The founder effect is a specific type of genetic drift that occurs when a small group of individuals establishes a new population, leading to a loss of genetic variation. - Genetic drift, on the other hand, is a broader concept that refers to random changes in allele frequencies in a population over time due to chance events. - Therefore, the founder effect is a specific scenario within the broader concept of genetic drift, where the establishment of a new population by a small number of individuals leads to genetic changes in the population.

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