Nursing Elites

1. Which molecule is primarily responsible for storing energy in cells?

• A. Glucose
• B. ATP
• C. Fatty acids
• D. Starch

Correct answer: B

Rationale: ATP is the correct answer because it is the molecule responsible for storing and providing energy in cells. Glucose is a source of energy but not primarily for storage. Fatty acids are more involved in energy production through oxidation. Starch is a polysaccharide used for energy storage in plants.

2. What is the primary function of the endoplasmic reticulum in a cell?

• A. Energy production
• B. Protein synthesis
• C. Waste removal
• D. Transport of materials

Correct answer: D

Rationale: The endoplasmic reticulum's primary function is the transport of materials within the cell. It acts as a network of membranes to assist in the transportation of proteins and other substances throughout the cell. Choice A, 'Energy production,' is incorrect because the endoplasmic reticulum is not directly involved in energy production. Choice B, 'Protein synthesis,' is incorrect as protein synthesis mainly occurs in ribosomes, although the endoplasmic reticulum is involved in modifying and transporting proteins. Choice C, 'Waste removal,' is also incorrect as waste removal is primarily handled by other organelles like lysosomes and peroxisomes.

3. Which is a byproduct of fermentation in muscle cells?

• A. Ethanol
• B. Pyruvic acid
• C. Lactic acid
• D. Oxygen

Correct answer: C

Rationale: Lactic acid is a byproduct of fermentation in muscle cells. During intense exercise or when oxygen is limited, muscle cells use anaerobic respiration to generate energy. This process breaks down glucose into lactic acid, which can cause muscle fatigue and soreness. Choice A, Ethanol, is not produced in muscle cells during fermentation. Choice B, Pyruvic acid, is an intermediate product in glucose metabolism but is not a byproduct of fermentation in muscle cells. Choice D, Oxygen, is not a byproduct of fermentation but a reactant in aerobic respiration.

4. What is the role of tRNA during protein synthesis?

• A. Carries amino acids to the ribosome
• B. Links nucleotides together
• C. Copies DNA sequences
• D. Replicates genetic material

Correct answer: A

Rationale: During protein synthesis, tRNA plays the crucial role of carrying amino acids to the ribosome. This process ensures that the correct amino acids are brought to the ribosome according to the mRNA sequence. Choice B, linking nucleotides together, refers to the role of RNA polymerase in transcription, not tRNA. Choice C, copying DNA sequences, is the function of DNA polymerase during DNA replication, while choice D, replicating genetic material, is an overarching function of DNA replication, not specific to tRNA's role in protein synthesis.

5. Which cellular structure is largely protective in function?

• A. Mitochondrion
• B. Vacuole
• C. Cell membrane
• D. Ribosome

Correct answer: C

Rationale: The correct answer is C: Cell membrane. The cell membrane, also known as the plasma membrane, is largely protective in function as it serves as a selectively permeable barrier that surrounds the cell, providing structural support and helping to maintain cell integrity. It regulates the movement of substances in and out of the cell, thus protecting the cell from harmful external factors while allowing essential nutrients to enter. Mitochondrion (choice A) is responsible for energy production, not primarily protective. Vacuole (choice B) is mainly involved in storage and transport. Ribosome (choice D) is involved in protein synthesis, not protective functions.

Similar Questions