KATHMANDU UNIVERSITY
University Examination
January/February 2026
Level: MBBS
Exam: I MBBS
Paper: IV – Respiratory System
Time: 2 hours 30 minutes
Full marks: 50
Date: February 8, 2026
#INSTRUCTION TO THE CANDIDATE
Answer each section in separate answer book.
Write brief, relevant and legible answers.
Illustrate your answer with well labeled diagrams wherever required.
All questions are compulsory.
#SECTION “B”
#Short Answer Questions
1.
a. Draw a well labelled diagram of bronchopulmonary segment of lung. (2)
b. Describe boundary, contents and applied anatomy of intercostal space. (3)
2.
Explain why TCA cycle is considered a central pathway of metabolism. (3)
3.
a. What is atypical pneumonia? Name two common pathogens associated with atypical pneumonia. (1+1=2)
b. Discuss the major virulence factors of Streptococcus pyogenes. (3)
4.
a. Describe the etiopathogenesis of Bronchial asthma. (3)
b. Write the histomorphology of squamous cell carcinoma of lung. (2)
5.
a. Classify bronchodilators with at least one example of each. Describe the pharmacological basis of use of salbutamol and ipratropium in Bronchial Asthma. (2+3=5)
b. Write down the rationale of combination of levocetirizine and montelukast in allergic cough. (2)
6.
a. Describe CO₂ transport in blood. (3)
b. Describe major factors that shifts Oxy-Hemoglobin dissociation curve at high altitude. (2)
#SECTION “C”
#Problem Based Questions
#Problem – I
7. A 65-years-old male, with a history of smoking for 30 years and a recent diagnosis of emphysema, visits clinic for persistent dyspnea on exertion and chronic cough that produces clear sputum. His symptoms have worsened over the past six months, particularly with physical activity. On examination his respiratory rate is elevated, and he demonstrates pursed-lip breathing. Auscultation reveals wheezing and decreased breath sounds. A CT scan of the chest shows bullae formation and hyperinflation. After evaluation he is prescribed long-acting bronchodilators and pulmonary rehabilitation.
a. Describe the histology of the affected structure. [Anatomy] (3)
b. Define lung compliance. Describe the pulmonary function test report to support diagnosis in the above case. [Physiology] (1+3=4)
c. Describe the role of elastase and α₁-antitrypsin in the development of symptoms in the above case. [Biochemistry] (3)
#Problem – II
8. A 55-years-old male visited medical OPD with low grade fever, evening rise in temperature and productive cough. He also complains of sweating for the past one month, loss of appetite and weight loss. On chest X-ray, nodular infiltrate was seen in apical region of right lung. His sputum smear for AFB was positive and he was diagnosed with pulmonary tuberculosis.
a. What are the common culture media used for isolation of the responsible pathogen? List out the modern techniques of diagnosis. [Microbiology] (1+2=3)
b. Describe the cytopathogenesis of the above disease. [Pathology] (3)
c. Enlist the first line anti-tubercular drugs. Write down the mechanism of action of any one of them. [Pharmacology] (2+2=4)
