A nurse is working in a walk-in clinic. She has been alerted that there is an outbreak of tuberculosis (TB). Which of the following clients entering the clinic today is most likely to have TB?

Correct Answer: C

Rationale: The correct answer is C, a 43-year-old homeless man with a history of alcoholism. This choice is most likely to have TB because individuals who are homeless and have a history of alcoholism are at higher risk for TB due to weakened immune systems and living conditions. Homelessness and alcoholism increase the likelihood of exposure to TB. Explanation for other choices: A: A 16-year-old female high school student - Less likely to have TB compared to homeless individuals with risk factors. B: A 33-year-old day-care worker - Possible but less likely compared to the homeless man with a history of alcoholism. D: A 54-year-old businessman - Least likely to have TB compared to the homeless individual with risk factors.

Correct Answer: D

Rationale: The correct answer is D because carbonic anhydrase catalyzes the conversion of carbon dioxide and water into bicarbonate ions and protons, not the formation of oxyhemoglobin. Step-by-step rationale: 1. Hemoglobin functions as a buffer by binding to hydrogen ions to help regulate pH levels in the blood. 2. Bicarbonate ions do tend to diffuse out of red blood cells into the plasma to maintain the balance of CO2 and pH. 3. The movement of molecules is indeed different in metabolically active tissues (where oxygen is released and CO2 is taken up) compared to the alveoli (where the opposite occurs). Therefore, choices A, B, and C are all correct statements, making D the false statement.

Correct Answer: D

Rationale: The correct order of structures in the respiratory passageways is D: pharynx, larynx, trachea, bronchi, bronchioles. This is the correct order because air enters the body through the pharynx, then passes through the larynx (voice box), followed by the trachea (windpipe), which branches into the bronchi, and then further divides into bronchioles. The other choices are incorrect because they do not follow the natural flow of air through the respiratory system. Choice A has the incorrect order starting with the pharynx, followed by the trachea, larynx, bronchi, and bronchioles. Choice B starts with the larynx, then pharynx, trachea, bronchioles, and bronchi, which is out of sequence. Choice C begins with the trachea, then pharynx, larynx, bronchi, and bronchioles, which is also incorrect

Correct Answer: B

Rationale: The correct answer is B: Pleurisy. Pleurisy is inflammation of the pleura, the lining around the lungs, causing severe chest pain. Emphysema (A) is a chronic lung condition causing shortness of breath, not chest pain. Asphyxia (C) is a condition of insufficient oxygen, not related to lung inflammation. Hypoxia (D) is low oxygen levels in tissues, not specific to lung covering inflammation. Pleurisy is the only choice directly related to inflammation of the lungs' covering, making it the correct answer.

Correct Answer: D

Rationale: The correct answer is D: Iron. Haemoglobin is a protein in red blood cells that carries oxygen throughout the body. Iron is an essential component of haemoglobin, binding to oxygen molecules and facilitating their transport. Sodium, potassium, and calcium do not play a direct role in the structure or function of haemoglobin, making them incorrect choices. Iron deficiency can lead to anemia due to the lack of adequate oxygen-carrying capacity in the blood.