Nursing Elites

1. Which of the following is NOT a mechanism of evolution?

• A. Natural selection
• B. Genetic drift
• C. Lamarckism
• D. Mutation

Correct answer: C

Rationale: A) Natural selection is a mechanism of evolution where individuals with advantageous traits are more likely to survive and reproduce, passing on those traits to the next generation. B) Genetic drift is a mechanism of evolution that occurs due to random changes in allele frequencies in a population. C) Lamarckism, also known as the inheritance of acquired characteristics, is a discredited theory that suggests organisms can pass on traits acquired during their lifetime to their offspring. This mechanism has been largely rejected by the scientific community. D) Mutation is a mechanism of evolution that introduces new genetic variation into a population, which can lead to the emergence of new traits and adaptations over time.

2. In the reaction 4Al + 3O2 → 2Al2O3, what is the mole ratio of aluminum to oxygen?

• A. 4:3
• B. 2:3
• C. 3:2
• D. 3:4

Correct answer: A

Rationale: The balanced chemical equation shows that 4 moles of aluminum react with 3 moles of oxygen to produce 2 moles of aluminum oxide. Therefore, the mole ratio of aluminum to oxygen is 4:3. Choice B (2:3) is incorrect because it does not reflect the correct ratio based on the balanced equation. Choice C (3:2) and Choice D (3:4) are also incorrect as they do not represent the correct mole ratio of aluminum to oxygen according to the balanced chemical equation.

3. When making a dilution, what do you do?

• A. Add more solvent to a concentrated solution
• B. Change the temperature of the solution
• C. Decrease the concentration of a solution
• D. All of the above

Correct answer: C

Rationale: When making a dilution, you decrease the concentration of a solution by adding more solvent to a concentrated solution. This process does not involve changing the temperature of the solution, so option B is incorrect. Option A is also incorrect because you are not adding more solute to the solution during dilution. Therefore, the correct answer is C) Decrease the concentration of a solution. Options A and B are incorrect as dilution involves adding more solvent, not solute, and does not require changing the temperature of the solution.

4. The adaptive immune system has two main branches: humoral and cell-mediated immunity. Which type of immune cell is primarily responsible for antibody production?

• A. Helper T cells
• B. Cytotoxic T cells
• C. B cells
• D. Natural killer cells

Correct answer: C

Rationale: B cells are primarily responsible for antibody production in the adaptive immune system. When activated, B cells differentiate into plasma cells, which are specialized to produce antibodies. Helper T cells play a crucial role in activating B cells, but they do not directly produce antibodies. Cytotoxic T cells are involved in cell-mediated immunity by killing infected cells, while natural killer cells are part of the innate immune system and target virus-infected and cancerous cells. Therefore, the correct answer is C (B cells) as they are directly involved in the production of antibodies, essential for humoral immunity.

5. How does the human eye focus light?

• A. Cornea
• B. Iris
• C. Lens
• D. Retina

Correct answer: C

Rationale: The human eye focuses light by adjusting the shape of its lens. The lens changes shape to allow the eye to focus on objects at different distances, a process known as accommodation. The cornea is the transparent outer covering of the eye that helps to focus light but does not change shape like the lens. The iris controls the size of the pupil to regulate the amount of light entering the eye. The retina is the light-sensitive layer at the back of the eye that receives and processes images but does not adjust the focus of light.

Similar Questions