Nursing Elites

1. Each statement regarding the correlation between vitamin D and sun exposure is accurate, except one. Which is the exception?

• A. The body can produce sufficient amounts of vitamin D from sunlight.
• B. UV radiation can convert a precursor of vitamin D to vitamin D3 by penetrating uncovered skin.
• C. Sunscreen blocks the formation of vitamin D3.
• D. By the age of 70 years, the skin generally produces vitamin D at only half the level it did at the age of 20 years.

Correct answer: C

Rationale: While UV radiation can penetrate uncovered skin and convert a precursor of vitamin D to vitamin D3, sunscreen does block the formation of vitamin D3. Sunscreen is recommended by dermatologists to prevent sunburn and reduce the risk of skin cancer. The other choices are correct: the body can produce sufficient vitamin D from sunlight, UV radiation can convert a precursor of vitamin D to vitamin D3, and skin generally produces less vitamin D as a person ages.

2. Each of the following describes the physiologic roles of water, except one. Which is the exception?

• A. Acts as a solvent for chemical reactions.
• B. Maintains stability of body fluids.
• C. Enables transport of nutrients and excretion of waste.
• D. Regulates temperature by pooling as perspiration on skin.

Correct answer: D

Rationale: The correct answer is D. Water regulates body temperature by evaporating as perspiration from the skin, not by pooling. When sweat evaporates from the skin, it takes away heat, which helps cool the body. Choices A, B, and C are correct because water acts as a solvent for chemical reactions, maintains the stability of body fluids, and enables the transport of nutrients and excretion of waste, respectively.

3. Match the energy-yielding nutrient to the amount of energy it provides to the body: Carbs, Fats, Proteins.

• A. Carbs - 4kcal/g
• B. Fats - 9kcal/g
• C. Proteins - 4kcal/g
• D. All of the above

Correct answer: D

Rationale: The correct answer is D, All of the above. Carbohydrates and proteins provide 4 kcal per gram, while fats provide 9 kcal per gram. Therefore, all three energy-yielding nutrients provide different amounts of energy to the body. Choice A, B, and C are incorrect because each of them individually provides a specific amount of energy per gram, but when considering all nutrients together, they collectively cover the spectrum of energy provision to the body.

4. _____ neutralizes stomach acid in the small intestine:

• A. saliva
• B. gastric mucus
• C. bicarbonate ions
• D. enzymes

Correct answer: C

Rationale: The correct answer is C: bicarbonate ions. Bicarbonate ions, secreted by the pancreas, neutralize the acidic chyme entering the small intestine from the stomach, creating a more suitable environment for digestive enzymes. Saliva (choice A) helps in the initial breakdown of food in the mouth, not in neutralizing stomach acid. Gastric mucus (choice B) protects the stomach lining from the acidic environment but does not neutralize the acid in the small intestine. Enzymes (choice D) facilitate chemical reactions in digestion but do not neutralize stomach acid.

5. Is the statement 'The metabolic rate is the highest after a few hours of sleep' true or false?

• A. True
• B. False
• C.
• D.

Correct answer: B

Rationale: The statement is false. The metabolic rate is actually lowest during sleep and increases upon waking. During sleep, the body conserves energy, leading to a lower metabolic rate. As the body wakes up and becomes active, the metabolic rate increases to support the body's functions and energy needs. Therefore, the metabolic rate is not the highest after a few hours of sleep, making the statement false.

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