Nursing Elites

1. Which of the following molecules acts as the genetic code's messenger?

• A. RNA
• B. Proteins
• C. DNA
• D. Carbohydrates

Correct answer: A

Rationale: The correct answer is RNA. RNA, particularly mRNA, serves as the messenger that carries genetic information from DNA to the ribosome, where proteins are synthesized. Proteins (choice B) are not the genetic code's messenger; they are synthesized based on the information carried by RNA. DNA (choice C) stores the genetic information but does not directly act as the messenger. Carbohydrates (choice D) are not involved in transmitting genetic information.

2. Which of the following is a group of three RNA nucleotides?

• A. A stop codon
• B. A codon
• C. An anticodon
• D. tRNA

Correct answer: B

Rationale: The correct answer is B - A codon. A codon is a sequence of three RNA nucleotides that specifies a particular amino acid or a stop signal during protein synthesis. Choice A, a stop codon, is a sequence of three nucleotides that signals the termination of protein synthesis. Choice C, an anticodon, is a group of three nucleotides found in tRNA that pairs with the complementary codon in mRNA. Choice D, tRNA, stands for transfer RNA, which is a type of RNA that carries amino acids to the ribosome during protein synthesis.

3. Phagocytes in the immune system are responsible for the biological action of which of the following?

• A. Secreting
• B. Consuming
• C. Altering
• D. Building

Correct answer: B

Rationale: The correct answer is B: Consuming. Phagocytes are cells that engulf and digest pathogens, dead cells, and other harmful particles, playing a crucial role in the immune system's defense. Phagocytes do not secrete substances, alter particles, or build structures; their primary function is to consume and eliminate harmful entities.

4. In which of the following does cellular respiration take place?

• A. Golgi apparatus
• B. Mitochondrion
• C. Chloroplast
• D. Ribosome

Correct answer: B

Rationale: The correct answer is B, Mitochondrion. Cellular respiration occurs in the mitochondria, where glucose is converted into energy through a series of metabolic processes. Choice A, Golgi apparatus, is incorrect as it is involved in modifying, sorting, and packaging proteins. Choice C, Chloroplast, is incorrect as it is the site of photosynthesis in plant cells, not cellular respiration. Choice D, Ribosome, is incorrect as it is responsible for protein synthesis, not energy production through cellular respiration.

5. What must first occur before a cell can be divided to grow, develop, and reproduce organisms?

• A. RNA replication
• B. DNA replication
• C. Gene replication
• D. Chromosome replication

Correct answer: B

Rationale: The correct answer is B: DNA replication. Before a cell can divide to grow, develop, and reproduce organisms, DNA replication must occur. This process ensures that each daughter cell receives an identical set of genetic information. Choices A, C, and D are incorrect because while RNA, genes, and chromosomes are essential components of cell division, DNA replication is the specific process that must first occur to ensure accurate transmission of genetic material.

Similar Questions