Nursing Elites

1. T cells in the immune system can be categorized into different types. What type of T cell directly kills infected body cells?

• A. Helper T cells
• B. Cytotoxic T cells
• C. Regulatory T cells
• D. Memory T cells

Correct answer: B

Rationale: Cytotoxic T cells directly kill infected body cells by recognizing specific antigens on the surface of infected cells and releasing cytotoxic substances to induce cell death, eliminating the infected cells. Helper T cells assist in coordinating the immune response, regulatory T cells help maintain immune tolerance, and memory T cells mount a faster and stronger response upon re-exposure to a previously encountered antigen. Therefore, the correct answer is cytotoxic T cells as they play a crucial role in directly targeting and destroying infected cells.

2. What is the term for a solution that contains the maximum amount of solute that can dissolve at a specific temperature and pressure?

• A. Saturated solution
• B. Unsaturated solution
• C. Dilute solution
• D. Concentrated solution

Correct answer: A

Rationale: A saturated solution is defined as a solution that has dissolved the maximum amount of solute possible at a specific temperature and pressure. In a saturated solution, any additional solute added will not dissolve, resulting in a visible precipitate. Choice B, unsaturated solution, refers to a solution where more solute can still be dissolved. Choices C and D, dilute solution and concentrated solution, do not specifically refer to the maximum amount of solute that can be dissolved at a given temperature and pressure, making them incorrect in this context.

3. What is the smallest bone in the human body?

• A. Stapes (Middle ear bone)
• B. Patella (Kneecap)
• C. Phalanges (Finger bones)
• D. Ribs

Correct answer: A

Rationale: The correct answer is A: Stapes (Middle ear bone). The stapes, located in the middle ear, is indeed the smallest bone in the human body. Despite its small size, the stapes is vital for hearing as it transmits and amplifies sound vibrations, contributing significantly to auditory perception. Choices B, C, and D are incorrect. The patella (kneecap) is the largest sesamoid bone in the human body, not the smallest bone. Phalanges are the bones in fingers and toes, not the smallest bone overall. Ribs are long bones that protect the chest cavity, not the smallest bone in the body.

4. Where does gas exchange take place in the respiratory system?

• A. Alveoli
• B. Bronchioles
• C. Bronchi
• D. Trachea

Correct answer: A

Rationale: Gas exchange in the respiratory system occurs in the alveoli, which are tiny air sacs in the lungs. Within the alveoli, oxygen from the inhaled air diffuses into the bloodstream, while carbon dioxide from the blood enters the alveoli to be exhaled. This exchange of gases is essential for the body to obtain oxygen and remove carbon dioxide, supporting vital bodily functions. The bronchioles (choice B), bronchi (choice C), and trachea (choice D) are part of the airway passage system that transports air to and from the alveoli but do not participate in gas exchange. Therefore, the alveoli play a crucial role in the respiratory system by facilitating gas exchange.

5. Which of the following is NOT a source of genetic variation in a population?

• A. Mutations in genes
• B. Genetic drift (random fluctuations in allele frequencies)
• C. Gene flow (movement of genes between populations)
• D. Blending inheritance (traits of parents are averaged in offspring)

Correct answer: D

Rationale: Rationale: A) Mutations in genes: Mutations are changes in the DNA sequence that can introduce new alleles into a population, leading to genetic variation. B) Genetic drift (random fluctuations in allele frequencies): Genetic drift refers to random changes in allele frequencies in a population, which can lead to genetic variation through chance events. C) Gene flow (movement of genes between populations): Gene flow occurs when individuals move between populations, bringing new alleles with them and increasing genetic variation within populations. D) Blending inheritance (traits of parents are averaged in offspring): Blending inheritance was a historical theory that suggested offspring inherit a blend of traits from their parents, leading to a reduction in genetic variation over time. However, this concept has been disproven by the understanding of Mendelian genetics, where traits are inherited independently and do not blend together. Therefore, blending inheritance does not contribute

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