Nursing Elites

1. What is the building block of RNA?

• A. Amino acid
• B. Nucleotide
• C. Protein
• D. Fatty acid

Correct answer: B

Rationale: Rationale: A) Amino acid: Amino acids are the building blocks of proteins, not RNA. B) Nucleotide: Nucleotides are the building blocks of RNA. A nucleotide consists of a nitrogenous base (adenine, guanine, cytosine, or uracil in RNA), a sugar (ribose in RNA), and a phosphate group. C) Protein: Proteins are made up of amino acids, not nucleotides. D) Fatty acid: Fatty acids are components of lipids, not RNA.

2. How does RNA polymerase differ from DNA polymerase?

• A. Both enzymes are identical in function and structure.
• B. RNA polymerase does not require a primer to initiate RNA synthesis.
• C. RNA polymerase can synthesize both RNA and DNA.
• D. RNA polymerase can only synthesize RNA, unlike DNA polymerase.

Correct answer: B

Rationale: Rationale: A) This statement is incorrect. RNA polymerase and DNA polymerase are not identical in function and structure. They have different roles in the cell. B) This statement is correct. Unlike DNA polymerase, RNA polymerase does not require a primer to initiate RNA synthesis. RNA polymerase can start the synthesis of RNA de novo. C) This statement is incorrect. RNA polymerase is specialized for synthesizing RNA, not DNA. DNA polymerase is responsible for synthesizing DNA. D) This statement is correct. RNA polymerase can only synthesize RNA, while DNA polymerase is responsible for synthesizing DNA.

3. Melanin, the pigment responsible for skin color, is produced by

• A. Keratinocytes (These cells produce keratin)
• B. Melanocytes
• C. Sebocytes (These cells produce sebum)
• D. Langerhans cells (These cells are part of the immune system)

Correct answer: B

Rationale: The correct answer is B: Melanocytes. Melanin, the pigment responsible for skin color, is produced by melanocytes, which are specialized cells located in the skin's epidermis. Melanocytes transfer melanin to keratinocytes, the predominant cell type in the epidermis, where it provides protection against UV radiation. Sebocytes produce sebum, an oily substance that helps moisturize the skin and hair. Langerhans cells are a type of immune cell that play a role in the skin's immune response. Therefore, the correct answer is B as melanocytes are specifically responsible for producing melanin.

4. The word "obscurity" can be replaced with which of the following without changing the meaning?

• A. Prominence
• B. Seclusion
• C. Destruction
• D. Transformation

Correct answer: B

Rationale: Both "obscurity" and "seclusion" imply being hidden or unknown. Prominence, destruction, and transformation do not convey the same meaning.

5. Which of the following describes a vector quantity?

• A. Speed
• B. Distance
• C. Mass
• D. Velocity

Correct answer: d

Rationale: Velocity is a vector quantity as it includes both magnitude (speed) and direction.

6. What is the main reason why elements in Group 18 (Noble gases) are generally unreactive?

• A. They have high atomic masses
• B. They lack valence electrons
• C. Their outermost electron shells are completely filled
• D. They exist as single atoms, not molecules

Correct answer: C

Rationale: Noble gases have their outermost electron shells filled with 8 electrons, achieving a stable configuration with minimal urge to gain or lose electrons, making them less prone to chemical reactions.

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