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. Which property of a substance refers to its ability to be stretched into thin wires?

• A. Conductivity
• B. Viscosity
• C. Ductility
• D. Malleability

Correct answer: c

Rationale: Ductility refers to a substance's ability to be stretched into thin wires without breaking.

3. What is the formula to calculate acceleration?

• A. Acceleration= Mass Force ​
• B. Acceleration= Force Mass ​
• C. Acceleration= Time Distance ​
• D. Acceleration= Time Change in Velocity ​

Correct answer: A

Rationale: Acceleration is calculated as the change in velocity divided by the time taken.

4. In the reaction 2H2 + O2 → 2H2O, how many moles of oxygen are required to react completely with 4 moles of hydrogen?

• A. 1
• B. 2
• C. 3
• D. 4

Correct answer: 2

Rationale: The balanced equation indicates a 1:1 ratio between H2 and O2, so 4 moles of H2 require 4 moles of O2, and 2 moles of H2 require 2 moles of O2.

5. Which vitamin is essential for calcium absorption and bone health?

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

Correct answer: C

Rationale: The correct answer is Vitamin D. Vitamin D plays a crucial role in calcium absorption in the intestines, which is essential for maintaining strong and healthy bones. It helps regulate calcium and phosphorus levels in the body, promoting bone mineralization and growth. Vitamin A is important for vision and immune function, not specifically for bone health. Vitamin C is essential for collagen synthesis but not directly involved in calcium absorption. Vitamin E is an antioxidant that protects cells from damage but does not have a direct role in bone health. Therefore, Vitamin D is the correct choice for supporting calcium absorption and bone health.

6. Why is it important to have control groups in scientific experiments?

• A. To please funding agencies and research institutions.
• B. To showcase the researcher's ingenuity and creativity.
• C. To allow comparison and isolate the effect of the variable being tested.
• D. To provide additional data points for statistical analysis.

Correct answer: C

Rationale: Control groups allow observation of what would happen without the tested variable, giving a baseline for comparison and isolating the specific effect being studied.

Similar Questions