Nursing Elites

1. Which functional group is commonly found in ketones?

• A. Hydroxyl
• B. Carbonyl
• C. Ester
• D. Amine

Correct answer: B

Rationale: Ketones contain a carbonyl functional group, which consists of a carbon atom double-bonded to an oxygen atom. This distinguishes ketones from other functional groups such as hydroxyl, ester, and amine. The presence of the carbonyl group, not hydroxyl (choice A), ester (choice C), or amine (choice D), is characteristic of ketones, making choice B, 'Carbonyl', the correct answer.

2. How do killer T cells recognize infected cells?

• A. The B cells flag the infected cells with amino acids.
• B. Tiny bits of the virus's RNA are left around the cell.
• C. Macrophages show up to help consume the infected cell.
• D. The T cells have receptors that recognize the proteins the virus leaves on the surface of the cell.

Correct answer: D

Rationale: Killer T cells recognize infected cells by detecting viral proteins displayed on the surface of these cells. The T cells possess receptors specifically designed to identify these viral proteins, allowing them to target and eliminate the infected cells. Choice A is incorrect because B cells are not directly involved in the recognition process of infected cells by killer T cells. Choice B is incorrect because tiny bits of the virus's RNA being left around the cell is not how killer T cells primarily recognize infected cells. Choice C is incorrect because while macrophages play a role in immune responses, they do not directly assist in the recognition of infected cells by killer T cells.

3. Which nitrogenous bases pair with each other in DNA?

• A. A-G and T-C
• B. A-T and C-G
• C. A-T and T-T
• D. C-C and G-G

Correct answer: B

Rationale: In DNA, nitrogenous bases pair with each other in a specific manner known as complementary base pairing. Adenine (A) always pairs with Thymine (T), and Cytosine (C) always pairs with Guanine (G). This pairing is essential for maintaining the structure and function of DNA. Option B is the correct answer as it correctly identifies the nitrogenous bases that pair with each other in DNA. Choices A, C, and D are incorrect because they do not follow the established base pairing rules in DNA. A-T and C-G are the complementary base pairs in DNA, ensuring the stability and replication fidelity of the genetic material.

4. During which phase of meiosis do chiasmata structures form?

• A. Prophase I
• B. Prophase II
• C. Metaphase I
• D. Metaphase II

Correct answer: A

Rationale: Chiasmata structures, where crossing over occurs, form during Prophase I of meiosis. This phase is characterized by homologous chromosomes pairing up and crossing over, leading to the exchange of genetic material between non-sister chromatids. Chiasmata are visible points of contact where genetic material has been exchanged, and they play a critical role in genetic diversity. Prophase II is the phase where chromosomes condense again in the second meiotic division, but chiasmata formation occurs in Prophase I. Metaphase I is the phase where homologous chromosomes align at the metaphase plate, not where chiasmata form. Metaphase II is the phase where replicated chromosomes align at the metaphase plate in the second meiotic division, but chiasmata formation occurs earlier in Prophase I.

5. In the process of osmosis, the solvent moves from an area of...

• A. Low solute concentration to high solute concentration
• B. Hotter solution to colder solution
• C. Colder solution to hotter solution
• D. High solute concentration to low solute concentration

Correct answer: D

Rationale: In the process of osmosis, solvent molecules move from an area of high solute concentration to low solute concentration. This movement occurs to equalize the solute concentrations on both sides of the semi-permeable membrane. As water tends to move towards higher solute concentrations, the solvent moves in this direction to balance the concentrations and establish equilibrium. Choices A, B, and C are incorrect because osmosis involves the movement of solvent, not solute, and it moves towards the area of higher solute concentration, not lower. Therefore, the correct answer is option D.

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