Nursing Elites

1. Which element is a critical component of DNA and RNA, essential for storing and transmitting genetic information?

• A. Oxygen
• B. Carbon
• C. Nitrogen
• D. Hydrogen

Correct answer: B

Rationale: Carbon is the correct answer as it is a critical element in DNA and RNA, forming the backbone of these molecules. Its ability to form diverse bonds allows for efficient storage and transmission of genetic information. Oxygen, nitrogen, and hydrogen are also present in DNA and RNA but do not serve as the primary backbone element for these molecules. Oxygen is involved in the structure but not as the backbone element. Nitrogen is present in the bases of nucleotides, and hydrogen bonds help stabilize the structure.

2. When ice melts, it undergoes a...

• A. Chemical change
• B. Physical change
• C. Nuclear change
• D. Radioactive decay

Correct answer: B

Rationale: When ice melts, it undergoes a physical change, transitioning from a solid state to a liquid state. This change does not involve altering the chemical composition of the ice, making it a physical change rather than a chemical change, nuclear change, or radioactive decay. Choice A, 'Chemical change,' is incorrect because a chemical change involves a rearrangement of atoms resulting in new substances. Choice C, 'Nuclear change,' is incorrect as it refers to changes in the nucleus of an atom, not the phase transition of ice. Choice D, 'Radioactive decay,' is incorrect as it involves the spontaneous disintegration of an unstable atomic nucleus, which is not the process occurring when ice melts.

3. Which vitamin plays a vital role in immune function?

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

Correct answer: C

Rationale: Vitamin D is the correct answer. It plays a vital role in immune function by regulating the immune system and enhancing the pathogen-fighting effects of monocytes and macrophages. Deficiency in Vitamin D has been linked to increased susceptibility to infections and autoimmune diseases, highlighting its importance in maintaining a healthy immune response. Vitamin A (Choice A) is essential for vision and skin health but is not primarily known for its role in immune function. Vitamin B12 (Choice B) is important for red blood cell formation and neurological function, not specifically immune function. Vitamin E (Choice D) acts as an antioxidant and is beneficial for skin health and cell function, but it is not primarily associated with immune system support.

4. Which of the following is an effect of high blood pressure?

• A. Smoking
• B. Excessive dietary salt
• C. Renal vessel damage
• D. Older age

Correct answer: C

Rationale: The correct answer is C: Renal vessel damage. High blood pressure can lead to damage in blood vessels throughout the body, including the kidneys. When blood vessels in the kidneys are affected, it can impair kidney function and potentially lead to kidney disease. Smoking (Choice A) and excessive dietary salt (Choice B) can contribute to high blood pressure but are not direct effects of high blood pressure itself. Older age (Choice D) is a risk factor for developing high blood pressure but is not a direct effect of high blood pressure.

5. Which of the following is an example of a chemical change?

• A. Dissolving sugar in water
• B. Boiling water
• C. Rusting iron
• D. Crushing ice

Correct answer: C

Rationale: Rusting iron is an example of a chemical change because it involves a chemical reaction where iron reacts with oxygen in the presence of water to form iron oxide (rust). This reaction results in a change in the chemical composition of the iron, unlike dissolving sugar in water, boiling water, or crushing ice, which are physical changes. Dissolving sugar in water is a physical change as sugar molecules remain unchanged but disperse in water. Boiling water is also a physical change as water changes its state from liquid to gas due to heat. Crushing ice is a physical change as the solid ice changes its physical form without altering its chemical composition.

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