Nursing Elites

1. Which enzyme plays a crucial role in DNA replication during the S phase of interphase?

• A. Helicase
• B. DNA polymerase
• C. Ligase
• D. Topoisomerase

Correct answer: B

Rationale: During the S phase of interphase, DNA replication takes place. DNA polymerase is the enzyme responsible for synthesizing new DNA strands by adding nucleotides in a complementary manner to the template strand. It plays a pivotal role in accurately replicating the entire genome. While helicase unwinds the double-stranded DNA for replication, topoisomerase relieves the tension in the DNA strands, and ligase joins the Okazaki fragments on the lagging strand. However, DNA polymerase directly participates in the synthesis of new DNA strands during replication, making it the correct answer.

2. Which neurotransmitter is associated with pleasure, reward, and motivation, and is often implicated in conditions such as addiction?

• A. Acetylcholine
• B. Dopamine
• C. Serotonin
• D. GABA (Gamma-aminobutyric acid)

Correct answer: B

Rationale: Dopamine is the neurotransmitter associated with pleasure, reward, and motivation. It plays a crucial role in the brain's reward system and is often implicated in conditions such as addiction. Acetylcholine is involved in muscle movement and memory, serotonin is linked to mood regulation, and GABA is an inhibitory neurotransmitter that helps reduce neuronal excitability. Therefore, the correct answer is dopamine as it aligns with the neurotransmitter functions related to pleasure, reward, and motivation, distinct from the roles of acetylcholine, serotonin, and GABA.

3. When two cars with different masses collide head-on, which car experiences a greater change in momentum?

• A. The car with the larger mass
• B. The car with the smaller mass
• C. Both cars experience the same change in momentum
• D. It depends on the initial velocities of the cars

Correct answer: C

Rationale: In a head-on collision between two cars, the law of conservation of momentum states that the total momentum of the isolated system remains constant before and after the collision. The change in momentum of one car is equal in magnitude but opposite in direction to the change in momentum of the other car. As a result, both cars experience the same change in momentum during the collision. Choice A is incorrect because the change in momentum is the same for both cars due to the conservation of momentum principle. Choice B is incorrect as the smaller mass car does not experience a greater change in momentum. Choice D is incorrect as the initial velocities of the cars do not determine which car experiences a greater change in momentum; it is solely dependent on the masses of the colliding cars.

4. What presents the correct order of cellular respiration?

• A. Glycolysis, Acetyl-CoA, Citric Acid Cycle, Electron Transport Chain
• B. Citric Acid Cycle, Glycolysis, Acetyl-CoA, Electron Transport Chain
• C. Glycolysis, Acetyl-CoA, Electron Transport Chain, Citric Acid Cycle
• D. Glycolysis, Citric Acid Cycle, Electron Transport Chain, Acetyl-CoA

Correct answer: A

Rationale: The correct order of cellular respiration is Glycolysis, Acetyl-CoA, Citric Acid Cycle, and Electron Transport Chain. Glycolysis initiates the breakdown of glucose in the cytoplasm, leading to the formation of pyruvate. This pyruvate is then converted to Acetyl-CoA in the mitochondria, which enters the Citric Acid Cycle to generate energy-rich molecules like NADH and FADH2. Finally, the Electron Transport Chain, located in the inner mitochondrial membrane, utilizes these energy carriers to produce ATP through oxidative phosphorylation. Choice B is incorrect because it starts with the Citric Acid Cycle, which comes after Glycolysis. Choice C is incorrect as it places the Citric Acid Cycle before the Electron Transport Chain. Choice D is incorrect by placing Acetyl-CoA last instead of before the Citric Acid Cycle.

5. What is the process of converting light energy into chemical energy called?

• A. Respiration
• B. Fermentation
• C. Photosynthesis
• D. Hydrolysis

Correct answer: C

Rationale: - Respiration (Option A) is the process by which cells break down glucose to release energy. - Fermentation (Option B) is an anaerobic process that also involves the breakdown of glucose to release energy. - Hydrolysis (Option D) is a chemical process that involves the breakdown of molecules by adding water. Photosynthesis (Option C) is the process by which green plants, algae, and some bacteria convert light energy into chemical energy in the form of glucose. During photosynthesis, plants use sunlight, carbon dioxide, and water to produce glucose and oxygen. This process is essential for the survival of plants and ultimately sustains life on Earth by providing oxygen for other organisms to breathe and serving as a source of energy in the food chain.

Similar Questions