Nursing Elites

1. A certain exam has 30 questions. A student gets 1 point for each question answered correctly and loses half a point for each question answered incorrectly; no points are gained or lost for questions left blank. If x represents the number of questions a student answers correctly and y represents the number of questions left blank, which of the following expressions represents the student's score on the exam?

• A. x - y/2
• B. x - y
• C. 30 - (x + y)
• D. 30 - x - y/2

Correct answer: A

Rationale: The student's score is calculated by adding the points earned for correct answers (x) and subtracting the points lost for incorrect answers (y/2). Therefore, the expression for the student's score on the exam is x - y/2. Option A is correct because it accurately represents this calculation. Option B (x - y) is incorrect as it does not account for the penalty of losing half a point for each incorrect answer. Option C (30 - (x + y)) is incorrect as it subtracts the total number of questions from the sum of correct and blank answers, which does not represent the scoring system. Option D (30 - x - y/2) is also incorrect as it incorrectly subtracts x from 30 and then deducts y divided by 2, which is not the correct scoring method for the exam.

2. How many feet are equal to 1 yard?

• A. 4 feet
• B. 3 feet
• C. 2 feet
• D. 5 feet

Correct answer: B

Rationale: The correct answer is B: 3 feet. This is because 1 yard is equivalent to 3 feet. The conversion factor between yards and feet is 1 yard = 3 feet. Choice A (4 feet) is incorrect as it represents the conversion of 1 yard to 4 feet, which is inaccurate. Choice C (2 feet) is incorrect as it underestimates the number of feet in 1 yard. Choice D (5 feet) is incorrect as it overestimates the number of feet in 1 yard.

3. Which of the following immune cells are part of the innate immune response?

• A. B-cells
• B. Cytotoxic T-cells
• C. Natural Killer cells
• D. Antigen-Presenting Cells

Correct answer: C

Rationale: Natural Killer cells are a crucial component of the innate immune response. They play a significant role in defending against infected or cancerous cells through their ability to identify and kill abnormal cells. B-cells (Choice A) and Cytotoxic T-cells (Choice B) are part of the adaptive immune response, which involves a more specific and targeted response to pathogens. Antigen-Presenting Cells (Choice D) are also part of the adaptive immune response, where they present antigens to activate other immune cells.

4. What is the primary function of the CRISPR-Cas9 system in gene editing?

• A. To amplify specific DNA sequences.
• B. To cut DNA at specific locations.
• C. To deliver genes into cells.
• D. To sequence entire genomes.

Correct answer: B

Rationale: The CRISPR-Cas9 system is a powerful tool used in gene editing to precisely target and cut DNA at specific locations within the genome. This system consists of a guide RNA that directs the Cas9 enzyme to the desired DNA sequence, where it creates a double-strand break. This break can then be repaired by the cell's natural DNA repair mechanisms, allowing for the introduction of specific genetic modifications. Options A, C, and D are incorrect as they do not accurately describe the primary function of the CRISPR-Cas9 system in gene editing. Amplifying DNA sequences, delivering genes into cells, and sequencing entire genomes are not the main functions of the CRISPR-Cas9 system, which is primarily focused on precise DNA cutting for targeted genetic modifications.

5. Which phenomenon describes the separation of light into its component colors when passing through a prism?

• A. Refraction
• B. Diffraction
• C. Dispersion
• D. Reflection

Correct answer: C

Rationale: Dispersion is the phenomenon that describes the separation of light into its component colors when passing through a prism. When white light enters a prism, it is refracted at different angles depending on its wavelength, causing the colors to spread out. Refraction is the bending of light as it passes from one medium to another, not the separation of colors. Diffraction is the bending of light around obstacles, not the separation of colors. Reflection is the bouncing back of light rays from a surface, not the separation of colors. In the context of a prism, dispersion plays a key role in the creation of a spectrum of colors by separating the different wavelengths present in white light.

Similar Questions