Nursing Elites

1. When ethanol (Câ‚‚Hâ‚…OH) reacts with sodium metal (Na), what is the product?

• A. Ethene (Câ‚‚Hâ‚„)
• B. Sodium ethoxide (Câ‚‚Hâ‚…ONa)
• C. Ethane (Câ‚‚H₆)
• 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.

2. Which of the following statements correctly describes the function of a physiological structure?

• A. The trachea connects the throat and the stomach.
• B. The esophagus joins the larynx with the lungs.
• C. The diaphragm controls the height of the thoracic cavity.
• D. The epiglottis covers the trachea during swallowing.

Correct answer: D

Rationale: The epiglottis is a flap of tissue that covers the trachea during swallowing to prevent food and liquids from entering the airway. This action helps direct food into the esophagus, ensuring proper passage into the digestive system and avoiding potential choking or aspiration into the lungs. Choices A, B, and C are incorrect because the trachea connects the larynx to the bronchi, the esophagus connects the throat to the stomach, and the diaphragm is a muscle that plays a vital role in breathing by separating the thoracic and abdominal cavities, aiding in respiration.

3. Which property of a substance remains constant regardless of changes in its shape or size?

• A. Mass
• B. Weight
• C. Volume
• D. Density

Correct answer: A

Rationale: The correct answer is 'Mass.' Mass is a measure of the amount of matter in an object and remains constant regardless of changes in its shape or size. Weight, volume, and density can all change depending on the conditions, but mass remains the same. Weight is the force exerted on an object due to gravity, which can change based on the gravitational pull. Volume is the amount of space an object occupies, which can change if the shape or size of the object changes. Density is the mass of a substance per unit volume, which can change if either the mass or volume changes. Therefore, in this scenario, mass is the property that remains constant regardless of changes in shape or size.

4. Which type of tissue connects muscles to bones?

• A. Ligaments
• B. Tendons
• C. Cartilage
• D. Muscles

Correct answer: B

Rationale: The correct answer is B: Tendons. Tendons connect muscles to bones, not bones to muscles. They play a crucial role in transmitting the force generated by muscles to move bones, enabling movement. Ligaments (choice A) connect bones to bones, providing stability to joints. Cartilage (choice C) is a connective tissue found in joints, providing cushioning and flexibility. Muscles (choice D) are responsible for generating force through contraction but do not directly connect muscles to bones.

5. Which of the following functions is not controlled by the autonomic nervous system?

• A. Digestion
• B. Walking
• C. Heartbeat
• D. Temperature regulation

Correct answer: B

Rationale: The correct answer is B: Walking. Walking is not directly controlled by the autonomic nervous system. Walking is a voluntary action governed by the somatic nervous system, which controls voluntary skeletal muscle movement. The autonomic nervous system, on the other hand, regulates functions that are involuntary, such as digestion, heartbeat, and temperature regulation. Choices A, C, and D are all functions controlled by the autonomic nervous system. Digestion involves processes like peristalsis and secretion of digestive enzymes, heartbeat is regulated by the autonomic nervous system to maintain blood pressure and circulation, and temperature regulation includes responses like sweating or shivering to maintain body temperature within a narrow range.

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