Nursing Elites

1. Balance the chemical equation: C4H10 + O2 → CO2 + H2O. What is the coefficient for oxygen?

• A. 5
• B. 6
• C. 7
• D. 8

Correct answer: B

Rationale: To balance the chemical equation, we need to ensure that the number of each type of atom is the same on both sides of the equation. In this case, there are 10 oxygen atoms on the right side (5 in CO2 and 5 in H2O). To balance this, we need to add a coefficient of 6 in front of O2 on the left side, resulting in 6 O2 molecules. This change will give us a total of 12 oxygen atoms on both sides, making the equation balanced. Choice A (5) is incorrect because it does not account for all the oxygen atoms present in the products. Choices C (7) and D (8) are incorrect as they would result in an imbalance in the number of oxygen atoms on both sides of the equation.

2. What is the primary composition of the stratum corneum, the outermost layer of the epidermis?

• A. Keratinized dead cells
• B. Melanocytes
• C. Langerhans cells
• D. Merkel cells

Correct answer: A

Rationale: The stratum corneum, the outermost layer of the epidermis, is primarily composed of keratinized dead cells. These cells are flattened, fully keratinized, and lack nuclei, serving a protective function for the skin. Melanocytes are responsible for producing melanin, providing skin pigmentation. Langerhans cells are involved in the immune response within the skin. Merkel cells are associated with sensory functions in the skin, particularly in touch sensations. Therefore, the correct answer is A as it accurately reflects the main constituent of the stratum corneum, which acts as a barrier against external factors.

3. Which structure in the respiratory system is responsible for voice production?

• A. Pharynx
• B. Larynx
• C. Trachea
• D. Bronchi

Correct answer: B

Rationale: The correct answer is the larynx. The larynx, commonly referred to as the voice box, is responsible for voice production in the respiratory system. It contains vocal cords that vibrate to produce sound. The pharynx is a passage for food and air, the trachea is a tubular structure that carries air to and from the lungs, and the bronchi are the main airway passages in the lungs. Therefore, choices A, C, and D are incorrect as they do not play a direct role in voice production.

4. Which part of the brainstem controls heart rate and breathing?

• A. Medulla oblongata
• B. Pons
• C. Midbrain
• D. Thalamus

Correct answer: A

Rationale: The medulla oblongata is a critical part of the brainstem responsible for regulating essential functions such as heart rate, breathing, and blood pressure. It houses centers that oversee these involuntary processes, making it the correct answer. The pons, midbrain, and thalamus do not primarily control heart rate and breathing, thus making them incorrect choices for this question.

5. What is the role of the pancreas in the digestive system?

• A. To store bile
• B. To secrete digestive enzymes
• C. To digest proteins
• D. To absorb nutrients

Correct answer: B

Rationale: The correct answer is B: 'To secrete digestive enzymes.' The pancreas plays a crucial role in the digestive system by secreting digestive enzymes that aid in breaking down food in the small intestine. These enzymes help in the digestion of carbohydrates, fats, and proteins, facilitating the absorption of nutrients from the digested food. Choice A is incorrect because the pancreas is not responsible for storing bile; the gallbladder stores bile. Choice C is incorrect because the pancreas secretes enzymes for protein digestion but does not digest proteins itself. Choice D is incorrect as the absorption of nutrients primarily occurs in the small intestine, not in the pancreas.

Similar Questions