Nursing Elites

1. What is the half-life of a radioactive isotope, and how does it relate to its decay rate?

• A. The time it takes for half of the initial sample to decay.
• B. The time it takes for all of the sample to decay.
• C. The rate at which new isotopes are created.
• D. The energy released during decay.

Correct answer: A

Rationale: The half-life of a radioactive isotope is the time it takes for half of the initial sample to decay. After one half-life, half of the radioactive atoms have decayed. The decay rate, however, refers to the rate at which radioactive atoms decay, which is not directly related to the half-life. Choice B is incorrect because it does not correctly define the half-life. Choice C is incorrect as it refers to the creation of new isotopes, not the decay process. Choice D is incorrect as it describes the energy released during decay, which is not the same as the concept of half-life.

2. What is the mass number of an element?

• A. The number of protons in an atom's nucleus.
• B. The number of neutrons in an atom's nucleus.
• C. The number of electrons in an atom's valence shell.
• D. The number of isotopes of an element.

Correct answer: B

Rationale: The mass number of an element represents the total number of protons and neutrons in an atom's nucleus. It specifically focuses on the number of neutrons in an atom's nucleus, which contributes to the overall mass of the atom. Therefore, the mass number is not solely determined by the number of protons, electrons, or isotopes. Choice A is incorrect because it refers to the atomic number, which is the number of protons in an atom's nucleus. Choice C is incorrect as the number of electrons in the valence shell is related to the atom's reactivity and bonding behavior, not the mass number. Choice D is incorrect because the mass number does not represent the number of isotopes of an element, but rather the sum of protons and neutrons in an atom's nucleus. Thus, option B, the number of neutrons in an atom's nucleus, is the correct choice.

3. What is the name of a condition where the heart rate is 118 beats per minute (bpm)?

• A. Tachycardia
• B. Apnea
• C. Bradycardia
• D. Tachypnea

Correct answer: A

Rationale: The correct answer is A: Tachycardia. Tachycardia is a condition characterized by a heart rate that exceeds the normal resting rate, typically above 100 bpm. In this case, a heart rate of 118 bpm falls within the range of tachycardia. Apnea (choice B) refers to the temporary cessation of breathing, not related to heart rate. Bradycardia (choice C) is a condition of an abnormally slow heart rate, opposite of the given heart rate. Tachypnea (choice D) is an abnormally rapid breathing rate, not related to heart rate.

4. Which vitamin is essential for proper absorption of calcium and plays a role in lung function?

• A. Vitamin A
• B. Vitamin B12
• C. Vitamin D
• D. Vitamin E

Correct answer: C

Rationale: The correct answer is Vitamin D. Vitamin D is crucial for the proper absorption of calcium in the intestines and is essential for maintaining lung function. It regulates calcium and phosphorus levels, crucial for healthy bones and teeth. Vitamin A is important for vision and immune function, not specifically for calcium absorption or lung function. Vitamin B12 is essential for nerve function and red blood cell production, not related to calcium absorption or lung function. Vitamin E is an antioxidant that helps protect cells from damage, but it is not directly involved in calcium absorption or lung function.

5. Which chamber of the heart is the largest?

• A. Right atrium
• B. Left atrium
• C. Right ventricle
• D. Left ventricle

Correct answer: D

Rationale: The correct answer is D, the left ventricle. The left ventricle is the largest and strongest chamber of the heart. It is responsible for pumping oxygenated blood to the entire body through the aorta, playing a crucial role in the circulatory system. Choices A, B, and C are incorrect. The right atrium receives deoxygenated blood from the body, the left atrium receives oxygenated blood from the lungs, and the right ventricle pumps deoxygenated blood to the lungs for oxygenation. However, the left ventricle is the largest chamber and performs the vital function of pumping oxygen-rich blood to the body.

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