Nursing Elites

1. Which vitamin is crucial for calcium absorption and synthesized in the skin upon sun exposure?

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

Correct answer: C

Rationale: The correct answer is Vitamin D. Vitamin D is essential for calcium absorption as it helps regulate calcium and phosphorus levels in the body. When the skin is exposed to sunlight, UVB rays convert a compound in the skin to vitamin D. This vitamin is vital for maintaining bone health and ensuring the overall calcium balance in the body. Choices A, B, and D are incorrect. Vitamin A is important for vision and immune function, Vitamin C is essential for collagen synthesis and immune function, and Vitamin E is an antioxidant that helps protect cells from damage by free radicals. However, none of these vitamins are primarily responsible for calcium absorption and synthesized in the skin upon sun exposure.

2. Which of the following best describes the process of osmosis?

• A. Movement of molecules against their concentration gradient
• B. Movement of water across a selectively permeable membrane
• C. Movement of water and solutes together
• D. Movement of large molecules through a membrane

Correct answer: B

Rationale: The correct answer is B. Osmosis is the process where water moves across a selectively permeable membrane from an area of low solute concentration to an area of high solute concentration. Choice A is incorrect because osmosis does not involve movement against the concentration gradient. Choice C is incorrect because osmosis primarily involves the movement of water, not water and solutes together. Choice D is incorrect as osmosis specifically refers to the movement of water molecules, not large molecules, through a membrane.

3. Which compound is a component of baking soda and is important for maintaining pH balance in the body?

• A. Potassium
• B. Sodium
• C. Calcium
• D. Sodium bicarbonate

Correct answer: D

Rationale: The correct answer is D, Sodium bicarbonate. Sodium bicarbonate, commonly known as baking soda, is a compound that plays a crucial role in maintaining pH balance in the body. When ingested, sodium bicarbonate acts as a buffer, helping to regulate the body's pH levels. It is essential for various physiological functions. Choices A, B, and C are incorrect. Potassium, calcium, and sodium are important minerals in the body but are not components of baking soda or directly responsible for maintaining pH balance in the same way as sodium bicarbonate.

4. Why is the simple columnar epithelium lining the small intestine crucial?

• A. Movement
• B. Support
• C. Absorption
• D. Insulation

Correct answer: C

Rationale: The simple columnar epithelium lining the small intestine is crucial for absorption. This type of epithelium is specialized for absorption due to its tall and closely packed cells, which increase the surface area available for nutrient absorption. The primary function of the small intestine is to absorb nutrients from digested food, and the simple columnar epithelium's structure aids in this process by providing a large surface area for absorption. Choices A, B, and D are incorrect because movement, support, and insulation are not primary functions associated with the simple columnar epithelium in the small intestine. While these functions are essential in other tissues or organs, absorption is the key role of the simple columnar epithelium in the small intestine.

5. Which of the following substances is NOT a product of cellular respiration?

• A. Carbon dioxide
• B. Water
• C. Oxygen
• D. ATP

Correct answer: C

Rationale: The correct answer is C. Oxygen is not a product of cellular respiration; instead, it is consumed during the process. During cellular respiration, glucose is broken down in the presence of oxygen to produce energy in the form of ATP, carbon dioxide, and water. Carbon dioxide is released as a waste product, water is a byproduct of the chemical reactions, and ATP is the energy currency used by cells. Therefore, options A, B, and D are all products or outcomes of cellular respiration, while oxygen is a reactant.

Similar Questions