Nursing Elites

1. Which element is used in fertilizers due to its role in plant cell division and growth?

• A. Potassium
• B. Phosphorus
• C. Calcium
• D. Magnesium

Correct answer: B

Rationale: Phosphorus is the correct answer. It is used in fertilizers due to its essential role in plant cell division and growth. Phosphorus is a key component of nucleic acids, such as DNA and RNA, which are essential for cell division and growth in plants. Potassium (Choice A) is important for overall plant health and functions like enzyme activation, but it is not specifically known for its role in cell division and growth. Calcium (Choice C) is crucial for cell wall structure and stability but not primarily for cell division. Magnesium (Choice D) is essential for chlorophyll production and photosynthesis, but it is not directly linked to plant cell division and growth.

2. Which organelle is responsible for producing energy in the cell?

• A. Nucleus
• B. Mitochondria
• C. Golgi apparatus
• D. Ribosome

Correct answer: B

Rationale: The correct answer is B: Mitochondria. Mitochondria are known as the powerhouse of the cell and are responsible for producing energy in the form of ATP through the process of cellular respiration. The other organelles listed, such as the nucleus, Golgi apparatus, and ribosome, have different functions within the cell and are not directly involved in energy production. The nucleus is responsible for storing genetic material and controlling cell activities. The Golgi apparatus is involved in modifying, sorting, and packaging proteins. Ribosomes are responsible for protein synthesis.

3. Which statement accurately defines power?

• A. Power is the amount of energy stored in an object
• B. Power is the rate at which energy is transferred or work is done
• C. Power is the maximum force exerted by an object
• D. Power is the resistance of an object to change in motion

Correct answer: B

Rationale: Power is defined as the rate at which energy is transferred or work is done. It is a measure of how quickly work is done or energy is transferred. Option A incorrectly refers to the amount of energy stored in an object, not power. Option C incorrectly refers to the maximum force exerted by an object, not power. Option D incorrectly refers to the resistance of an object to change in motion, not power. Therefore, the correct definition of power is that it is the rate at which energy is transferred or work is done.

4. What happens during a physical change in matter?

• A. A new substance with different properties is formed
• B. The chemical composition of the substance changes
• C. The original substance can be recovered by physical means
• D. Energy is either released or absorbed

Correct answer: C

Rationale: During a physical change in matter, the original substance undergoes a change in its physical state or appearance without any change in its chemical composition. This means that the original substance can be recovered by physical means, such as melting, freezing, boiling, or condensing. No new substance is formed (option A), the chemical composition remains the same (option B), and energy changes can occur but are not a defining characteristic of a physical change (option D). The ability to recover the original substance by physical means distinguishes physical changes from chemical changes.

5. How does the stability of an atom's nucleus influence its radioactive decay?

• A. Stable nuclei never undergo radioactive decay.
• B. Unstable nuclei are more likely to decay through various processes.
• C. Decay releases energy, making stable nuclei more prone to it.
• D. The element's position on the periodic table determines its decay rate.

Correct answer: B

Rationale: Unstable nuclei are more likely to decay through various processes. The stability of an atom's nucleus is a crucial factor in determining whether it will undergo radioactive decay. Unstable nuclei have an excess of either protons or neutrons, causing an imbalance in the nucleus. To achieve a more stable configuration, these nuclei will undergo radioactive decay by emitting particles or energy. On the contrary, stable nuclei are less likely to undergo radioactive decay as they possess a balanced number of protons and neutrons. Choice A is incorrect because stable nuclei can still undergo radioactive decay, albeit less frequently. Choice C is incorrect as decay does not make stable nuclei more prone to it; rather, it stabilizes them. Choice D is incorrect because an element's decay rate is primarily determined by the nucleus's stability, not its position on the periodic table.

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