Nursing Elites

1. Which element is used in fluorescent lamps and emits ultraviolet light when excited?

• A. Mercury
• B. Neon
• C. Argon
• D. Krypton

Correct answer: A

Rationale: Mercury is the correct element used in fluorescent lamps to emit ultraviolet light when excited. When an electric current passes through the mercury vapor inside the lamp, it generates ultraviolet (UV) light. This UV light then excites the phosphors coated on the inner surface of the lamp, causing them to emit visible light. Neon, argon, and krypton are not commonly used in fluorescent lamps for this purpose. Neon is primarily used in neon signs, argon is used in incandescent and fluorescent bulbs for inertia gas, and krypton is mainly used in certain types of specialized light bulbs for its specific properties.

2. What is the energy required to break a chemical bond called?

• A. Kinetic energy
• B. Potential energy
• C. Activation energy
• D. Bond energy

Correct answer: C

Rationale: Activation energy is the energy required to break a chemical bond and initiate a chemical reaction. It is the minimum amount of energy needed to start a chemical reaction by breaking bonds in the reactant molecules. Kinetic energy (option A) is the energy of motion and is not directly related to breaking chemical bonds. Potential energy (option B) is stored energy that can be converted into other forms of energy but is not specifically about breaking chemical bonds. Bond energy (option D) refers to the energy required to break a particular chemical bond in a molecule and is not the general term for the energy needed to break any chemical bond. Activation energy is crucial in determining the rate of a chemical reaction as it affects the probability of reactant molecules colliding with sufficient energy to surpass the energy barrier and form products.

3. Which structure do cells rely on for movement?

• A. Flagellum
• B. Microtubule
• C. Pili
• D. Vesicle

Correct answer: A

Rationale: The correct answer is A: Flagellum. Cells rely on flagella for movement, which are whip-like structures that propel the cell forward through their whipping motion. Flagella provide motility to single-celled organisms and certain cells in multicellular organisms. Microtubules, on the other hand, provide structural support to the cell and play a role in intracellular transport. Pili are short, hair-like structures used for attachment to surfaces or other cells, not for movement. Vesicles are membrane-bound sacs involved in intracellular transport, aiding in the movement of substances within the cell, but not in the movement of the cell itself.

4. Which of the following organelles is responsible for protein production in the cell?

• A. Ribosomes
• B. Golgi apparatus
• C. Mitochondria
• D. Lysosomes

Correct answer: A

Rationale: The correct answer is A: Ribosomes. Ribosomes are the organelles responsible for protein synthesis in the cell. They can be found either freely floating in the cytoplasm or attached to the endoplasmic reticulum. The Golgi apparatus (Choice B) is involved in processing and packaging proteins, not protein production. Mitochondria (Choice C) are responsible for energy production, not protein synthesis. Lysosomes (Choice D) are involved in digestion and waste removal, not protein production.

5. What is the process by which cells respond to external stimuli, such as chemicals, temperature, or touch, called?

• A. Signal transduction
• B. Homeostasis
• C. Adaptation
• D. Metabolism

Correct answer: A

Rationale: Signal transduction is the correct answer. It is the process by which cells respond to external stimuli like chemicals, temperature, or touch. When a cell receives a signal from its environment, it triggers a series of molecular events leading to a specific cellular response. This process involves transmitting signals from the cell surface to the interior, triggering various cellular activities. Homeostasis, on the other hand, refers to an organism's ability to maintain internal stability in response to external changes. Adaptation involves an organism adjusting to its environment over time through genetic changes or behavioral modifications, which is distinct from the process of cells responding to immediate external stimuli. Metabolism, although essential for cellular functions, is not specifically about cells responding to external stimuli but rather the biochemical processes involved in energy production, storage, and utilization within cells.

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