Nursing Elites

1. Vaccines work by stimulating the immune system to develop:

• A. A physical barrier against pathogens
• B. An inflammatory response
• C. Immunological memory to a specific pathogen
• D. Phagocytes to engulf pathogens

Correct answer: C

Rationale: The correct answer is C: 'Immunological memory to a specific pathogen.' Vaccines work by introducing a harmless form of a pathogen or a piece of it to stimulate the immune system. This exposure triggers the production of antibodies and memory cells specific to that pathogen. These memory cells 'remember' the pathogen, allowing the immune system to respond more effectively and rapidly if exposed to the actual pathogen in the future. Options A, B, and D are incorrect because vaccines do not create a physical barrier, induce a general inflammatory response, or directly cause phagocytes to engulf pathogens; instead, vaccines enhance the immune system's ability to recognize and combat specific pathogens.

2. A 10 kg box rests on a frictionless surface. A horizontal force of 20 N is applied to the box. What is the box's acceleration?

• A. 0.5 m/s²
• B. 1 m/s²
• C. 2 m/s²
• D. 10 m/s²

Correct answer: C

Rationale: Use Newton's second law, F = ma, where F is the net force, m is the mass, and a is the acceleration. Since there is no friction, the net force equals the applied force (20 N). Therefore, a = F/m = 20 N / 10 kg ≈ 2 m/s².

3. The structural and functional unit of the kidney responsible for filtering blood is the:

• A. Nephron
• B. Ureter
• C. Urethra
• D. Bladder

Correct answer: A

Rationale: The correct answer is A, Nephron. The nephron is the structural and functional unit of the kidney responsible for filtering blood. It consists of the glomerulus, renal tubule, and collecting duct. The nephron's filtration process plays a crucial role in removing waste products, regulating electrolyte balance, and maintaining blood pressure. The other options, B: Ureter, C: Urethra, and D: Bladder, are not responsible for filtering blood. The ureter transports urine from the kidneys to the bladder, the urethra is responsible for urine excretion from the bladder, and the bladder stores urine before excretion. Therefore, the nephron is specifically designed for the filtration process within the kidney.

4. How does the acceleration of an object change if the force acting on it is doubled?

• A. Acceleration is halved
• B. Acceleration doubles
• C. Acceleration remains unchanged
• D. Acceleration quadruples

Correct answer: b

Rationale: According to Newton's second law (F = ma), if force is doubled and mass remains constant, acceleration doubles.

5. Which vitamin plays a crucial role in calcium absorption in the small intestine?

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

Correct answer: C

Rationale: The correct answer is C: Vitamin D. Vitamin D plays a crucial role in calcium absorption in the small intestine because it helps regulate the levels of calcium and phosphorus in the body. When vitamin D is present, it stimulates the production of proteins that facilitate the absorption of calcium from the intestine into the bloodstream. Without adequate levels of vitamin D, the body struggles to absorb calcium efficiently, which can lead to weakened bones and other health issues. While vitamins A, C, and E are important for various functions in the body, they do not directly impact calcium absorption in the same way that vitamin D does.

6. What is the term for the process of converting a liquid into a gas at a temperature below its boiling point?

• A. Vaporization
• B. Evaporation
• C. Condensation
• D. Sublimation

Correct answer: B

Rationale: Evaporation is the process of converting a liquid into a gas at a temperature below its boiling point. The other choices describe different phase changes.

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