Nokea
The 75-year-old patient presents to the emergency department with shortness of breath,
fatigue, and a dry cough. When information leads the nurse to suspect that this patient should
undergo workup for histoplasmosis?
- A. The patient reports drinking pond water
- B. The patient lives on a farm and raises chickens.
- C. The patient recently went hunting in a wooded area.
- D. The patient owns a landscaping company.
Correct Answer: B
Rationale: The correct answer is B because living on a farm and raising chickens increases the risk of exposure to histoplasmosis, a fungal infection commonly found in soil contaminated with bird droppings. Raising chickens can lead to exposure to bird feces, which may contain the histoplasma fungus. The other choices (A, C, D) do not directly involve exposure to environments where the fungus is commonly found, making them less likely to lead to histoplasmosis workup.
You may also like to solve these questions
Which of the following anatomical structures is not part of the conducting zone?
- A. pharynx
- B. nasal cavity
- C. alveoli
- D. bronchi
Correct Answer: C
Rationale: The correct answer is C: alveoli. The conducting zone of the respiratory system includes structures that transport air to and from the gas exchange sites. Alveoli are the primary sites of gas exchange, not part of the conducting zone. Pharynx (A), nasal cavity (B), and bronchi (D) are all part of the conducting zone as they help in air transportation but do not directly participate in gas exchange like alveoli do. Therefore, alveoli is the correct answer as it does not belong to the conducting zone.
The function of tracheal cilia is to
- A. Pass mucus out
- B. Pass mucus in
- C. Pass air out
- D. Pass air out
Correct Answer: A
Rationale: The correct answer is A: Pass mucus out. Tracheal cilia help move mucus, which contains dust, debris, and pathogens, out of the respiratory tract to prevent infections and maintain clear airways. This process is known as mucociliary clearance. Choices B, C, and D are incorrect because tracheal cilia do not pass mucus in, pass air out, or pass air in. Tracheal cilia specifically function to clear mucus out of the respiratory tract.
When Bohr effect occurs due to increased CO2 tension, Oxygen affinity of Hb decreases. The reason for increased CO2 tension is
- A. Increase in P50
- B. Decrease in P50
- C. High CO2 content
- D. High O2 content
Correct Answer: A
Rationale: The correct answer is A because an increase in P50 indicates a decrease in oxygen affinity of hemoglobin (Hb), as seen in the Bohr effect. When CO2 tension rises, it forms carbonic acid in the blood, leading to a decrease in pH. This decrease in pH causes a right shift in the oxygen-hemoglobin dissociation curve, resulting in lower oxygen affinity of Hb. Decreasing P50 reflects this reduced affinity. Choices B, C, and D are incorrect because a decrease in P50, high CO2 content, and high O2 content would not lead to a decrease in oxygen affinity as observed in the Bohr effect.
Myoglobin is a muscle hemoglobin which exhibits Hyperbolic oxygen dissociation curve indicating its great affinity towards Oxygen (Non-cooperative binding). The Hyperbolic nature of the curve is due to
- A. Single polypeptide (153 amino acids) and Monomeric nature
- B. High concentration in the muscle
- C. Muscle protein
- D. Quarternary structure
Correct Answer: A
Rationale: Step-by-step rationale for choice A being correct:
1. Myoglobin is composed of a single polypeptide chain with 153 amino acids, making it monomeric.
2. Being monomeric, myoglobin does not exhibit cooperative binding, leading to a hyperbolic oxygen dissociation curve.
3. The lack of multiple subunits in myoglobin results in non-cooperative binding and a hyperbolic curve.
4. The monomeric nature allows myoglobin to have a simple structure, enhancing its affinity for oxygen.
Summary of why other choices are incorrect:
B: High concentration in the muscle does not directly explain the hyperbolic curve.
C: Being a muscle protein does not inherently determine the hyperbolic nature of the oxygen dissociation curve.
D: Quaternary structure would involve multiple subunits, leading to cooperative binding and a sigmoidal oxygen dissociation curve.
Smoking has been shown to cause
- A. bronchitis.
- B. emphysema.
- C. lung cancer.
- D. all of the above
Correct Answer: D
Rationale: Smoking causes bronchitis due to inflammation of bronchial tubes, emphysema by damaging air sacs in lungs, and lung cancer from carcinogens. Therefore, "D: all of the above" is correct as smoking leads to all these respiratory health issues. Choices A, B, and C are incorrect as smoking is linked to all three conditions.