Nursing Elites

1. Isotopes are variants of a single element that differ in:

• A. Having the same number of protons but varying numbers of neutrons
• B. Having the same number of neutrons but varying numbers of protons
• C. Having the same mass but different atomic numbers
• D. None of the above

Correct answer: A

Rationale: Isotopes are variants of a single element that have the same number of protons, the defining characteristic of an element. They differ in the number of neutrons they possess, leading to isotopes having different atomic masses while retaining the same chemical properties. Choice B is incorrect because isotopes have the same number of neutrons and differ in the number of protons. Choice C is incorrect because isotopes have different masses due to varying numbers of neutrons, not different atomic numbers. Choice D is incorrect as isotopes do differ in the number of neutrons they possess.

2. When ethanol (C₂H₅OH) reacts with sodium metal (Na), what is the product?

• A. Ethene (C₂H₄)
• B. Sodium ethoxide (C₂H₅ONa)
• C. Ethane (C₂H₆)
• D. Sodium acetate (CH₃COONa)

Correct answer: B

Rationale: When ethanol (C₂H₅OH) reacts with sodium metal (Na), the product formed is Sodium ethoxide (C₂H₅ONa). This reaction is a classic example of a metal displacing hydrogen in an alcohol to form an alkoxide. In this specific case, sodium replaces the hydrogen in ethanol, resulting in the formation of sodium ethoxide. Choice A, Ethene (C₂H₄), is incorrect as it is a different compound formed from the dehydration of ethanol, not its reaction with sodium. Choice C, Ethane (C₂H₆), is incorrect as it is a saturated hydrocarbon, not the product of the reaction of ethanol with sodium metal. Choice D, Sodium acetate (CH₃COONa), is incorrect as it involves acetic acid, not ethanol, reacting with sodium to form the salt sodium acetate.

3. Which type of cell secretes antibodies?

• A. Bacterial cells
• B. Viral cells
• C. Lymph cells
• D. Plasma cells

Correct answer: D

Rationale: The correct answer is D: Plasma cells. Plasma cells are a type of white blood cell that secretes antibodies. Antibodies are essential components of the immune system, as they help in identifying and neutralizing pathogens. Choice A, B, and C are incorrect as bacterial cells and viral cells do not secrete antibodies, and lymph cells are involved in the immune response but do not secrete antibodies like plasma cells.

4. What is the term for the process of bone formation and breakdown?

• A. Ossification
• B. Resorption
• C. Remodeling
• D. All of the above

Correct answer: C

Rationale: The correct term for the process of bone formation and breakdown is remodeling. Ossification specifically refers to bone formation, while resorption pertains to bone breakdown. Remodeling encompasses both processes, as it involves the continuous cycle of bone formation and resorption to maintain bone strength and structure. Choice A, 'Ossification,' is incorrect as it only refers to bone formation. Choice B, 'Resorption,' is incorrect as it only refers to bone breakdown. Choice D, 'All of the above,' is incorrect as it includes terms that are not comprehensive of both bone formation and breakdown.

5. Which of the following conditions is characterized by a high percentage of CO2 and a very low percentage of O2 in the blood?

• A. Asphyxia
• B. Emphysema
• C. Eupnea
• D. Hypoxia

Correct answer: A

Rationale: Asphyxia is the correct answer as it refers to a condition with high CO2 and low O2 levels in the blood. Asphyxia can result in oxygen deprivation and excess carbon dioxide in the bloodstream, posing a life-threatening situation if not treated promptly. Emphysema is a chronic lung disease characterized by the damage to the air sacs in the lungs, leading to breathing difficulties. Eupnea denotes normal breathing without any abnormalities. Hypoxia, on the other hand, involves low oxygen levels reaching the body's tissues, which can result from various causes such as reduced oxygen in the air or respiratory issues.

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