Nursing Elites

1. Which element is used in jewelry due to its malleability and resistance to tarnish?

• A. Iron
• B. Copper
• C. Gold
• D. Silver

Correct answer: C

Rationale: Gold is the correct answer. Gold is a popular choice for jewelry due to its exceptional malleability, allowing it to be easily shaped into intricate designs. Moreover, gold is resistant to tarnish, ensuring the jewelry retains its beauty over time. Iron is not commonly used in jewelry due to its susceptibility to rusting. Copper is also not as popular in jewelry making as gold due to its tendency to tarnish and cause skin discoloration. While silver is used in jewelry, it is more prone to tarnish compared to gold, making it less ideal for long-lasting pieces.

2. What is the function of introns in eukaryotic genes?

• A. They code for protein sequences.
• B. They are involved in gene regulation.
• C. They are removed during mRNA processing.
• D. They are non-functional remnants of ancient DNA.

Correct answer: C

Rationale: A) Introns do not code for protein sequences. Exons are the segments of DNA that code for proteins. B) While introns can indirectly influence gene regulation, their primary function is not directly involved in gene regulation. C) Introns are non-coding regions of DNA that are transcribed into pre-mRNA but are removed during mRNA processing through a process called splicing. This allows only the exons to be included in the mature mRNA that will be translated into proteins. D) While introns were once thought to be non-functional remnants of ancient DNA, research has shown that they can have regulatory functions and play a role in gene expression.

3. Where does the maturation of T-cells and the production of T-cell receptors occur?

• A. Thymus
• B. Spleen
• C. Lymph nodes
• D. Bone marrow

Correct answer: A

Rationale: The correct answer is the Thymus. T-cells mature and develop their receptors in the thymus gland, making it a vital organ for the immune system. The thymus provides the necessary environment for T-cells to differentiate and acquire their specific receptors and functions, which are essential for their role in the adaptive immune response. The spleen, lymph nodes, and bone marrow are all important components of the immune system, but they do not primarily serve as sites for T-cell maturation and T-cell receptor production.

4. In meiosis, how many divisions occur, and how many daughter cells are produced?

• A. One division, two daughter cells
• B. Two divisions, four daughter cells
• C. Four divisions, eight daughter cells
• D. Eight divisions, sixteen daughter cells

Correct answer: B

Rationale: In meiosis, there are two divisions: meiosis I and meiosis II. During meiosis I, homologous chromosomes separate, resulting in two daughter cells with half the number of chromosomes as the parent cell. In meiosis II, sister chromatids separate, resulting in a total of four daughter cells, each with a haploid set of chromosomes. Therefore, meiosis involves two divisions and produces four daughter cells. Choice A is incorrect because meiosis involves two divisions, not one. Choice C and D are incorrect as meiosis does not go through four or eight divisions, resulting in eight or sixteen daughter cells.

5. How many chromosomes must a normal human sperm cell contain?

• A. An X chromosome.
• B. A Y chromosome.
• C. 23 chromosomes.
• D. Both an X and Y chromosome.

Correct answer: C

Rationale: A normal human sperm cell contains a total of 23 chromosomes, half the number found in a typical human cell which has 46 chromosomes. This includes 22 autosomes and one sex chromosome, which can be either an X or a Y chromosome. Therefore, the correct answer is that a normal human sperm cell must contain 23 chromosomes. Choices A and B are incorrect because a single sex chromosome alone does not represent the total number of chromosomes in a sperm cell. Choice D is incorrect because a sperm cell carries only one sex chromosome, either X or Y, not both.

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