Nursing Elites

1. Which of the following statements is most accurate regarding the transcription of DNA?

• A. RNA uses reverse transcriptase to make mRNA
• B. DNA uses mRNA to produce tRNA
• C. RNA creates a duplicate copy of DNA
• D. RNA copies DNA to produce mRNA

Correct answer: D

Rationale: The correct answer is D. During transcription, RNA copies DNA to produce mRNA, which carries the genetic information from DNA to the ribosomes for protein synthesis. Choice A is incorrect because reverse transcriptase is not involved in the transcription of DNA. Choice B is incorrect as DNA does not use mRNA to produce tRNA; tRNA is produced through a different process. Choice C is incorrect as RNA does not create a duplicate copy of DNA during transcription; it synthesizes mRNA by copying the DNA template.

2. What function does cholesterol, a phospholipid, serve within the cell membrane?

• A. It builds up fats to make the structure more flexible
• B. It allows protein channels to form
• C. It makes the structure very rigid and impermeable
• D. It stabilizes the membrane structure

Correct answer: D

Rationale: Cholesterol helps to maintain the fluidity and stability of the cell membrane by fitting between the phospholipid molecules. Choice A is incorrect because cholesterol does not build up fats in the cell membrane. Choice B is incorrect as protein channels are formed by proteins, not cholesterol. Choice C is incorrect as cholesterol actually helps regulate the fluidity of the membrane, making it less rigid and more permeable.

3. The bilayer of the cellular membrane consists of phospholipids with all except which of the following scattered throughout?

• A. Nucleic acids
• B. Cholesterol
• C. Proteins
• D. Glycoproteins

Correct answer: A

Rationale: The cellular membrane is composed of a phospholipid bilayer with cholesterol, proteins, and glycoproteins distributed throughout. Nucleic acids are not found within the cellular membrane. Cholesterol helps maintain membrane fluidity, while proteins and glycoproteins play important roles in cell signaling, transport, and structural support.

4. Prophase is the first stage of mitosis. Which of the following best describes chromosomes during this stage?

• A. They are gathered on either side of the separating cell
• B. They are all aligned along the metaphase plate
• C. They are attached to the spindle
• D. They are visibly separate

Correct answer: D

Rationale: The correct answer is D. During prophase, the chromosomes condense and become visible as distinct structures under a microscope. Choice A is incorrect as chromosomes are not gathered on either side of the separating cell during prophase. Choice B is incorrect because chromosomes align along the metaphase plate during the subsequent stage, metaphase. Choice C is incorrect as chromosomes become attached to the spindle fibers during prometaphase, the stage following prophase.

5. Which of the following molecules contains the code required for replication?

• A. Deoxyribonucleic acid (DNA)
• B. Transfer RNA (tRNA)
• C. Messenger RNA (mRNA)
• D. Ribonucleic acid (RNA)

Correct answer: A

Rationale: The correct answer is A: Deoxyribonucleic acid (DNA). DNA contains the genetic information essential for replication, ensuring the accurate transmission of genetic material from one generation to the next. Choice B, Transfer RNA (tRNA), is involved in protein synthesis, not replication. Choice C, Messenger RNA (mRNA), carries genetic information from DNA to the ribosome but does not contain the code for replication. Choice D, Ribonucleic acid (RNA), is a broader category that includes both mRNA and tRNA, but the specific molecule containing the code required for replication is DNA.

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