UPSC Mains 2026 Medical Science Optional Paper I questions

54 questions from the Civil Services (Main) Examination 2026. Official UPSC paper (PDF) · All Medical Science Optional PYQs

1. Describe the hip joint under the following headings: (i) Factors responsible for its stability (ti) Arterial supply of upper end of femur along with mechanism of avascular necrosis of femoral head

2. A 55-year-old male is operated for a lung tumour. During the postoperative stay, he develops shortness of breath. His examination shows paradoxical movement of right hemidiaphragm during inspiration and same was also recorded on MR imaging. In the above case— (i) explain the anatomical basis of his clinical findings; (ti) enumerate the major openings of diaphragm and their vertebral levels, along with all the structures passing through each of them.

3. A 55-year-old male presented in surgery OPD with yellow-coloured sclera and greasy stools. On detailed examination, he was diagnosed with carcinoma of head of pancreas. Based on these clinical findings, discuss the following: (i) Serum markers of cholestasis; (iti) Cause of greasy stools

4. Describe the phases of action potential in a neuron. State the difference in 'conduction' between benign and unmyelinated neuron.

5. With the help of a suitable well-labelled diagram, explain the principal connections of basal ganglia.

6. A 32-year-old male is brought to the emergency department following a road traffic accident. His clinical examination shows that his arm is adducted and medially rotated, elbow is extended and forearm is pronated. Sensory loss is also noted on lateral aspect of his forearm. His MR scan shows involvement of upper part of brachial plexus. Based on this clinical scenario, answer the following: (i) Identify the site of involvement of brachial plexus, using a diagram. (i) Explain the anatomical basis of motor and sensory loss.

   5 marks

7. Describe the role of various proteins regulating the iron absorption, transport and storage in the body.

8. Explain the biochemical role of vitamin 86. Explain why the deficiency of vitamin B6 causes pellagra-like symptoms.

9. Describe the functions of growth hormone. Write a note on the regulation of secretion of growth hormone.

10. Discuss the mechanism of action of insulin at receptor level. 5 Name 3

11. Name the ligaments of ovary and their role in ovarian torsion and its complications.

12. Explain the surgical importance of anatomical relations of structures in ovarian fossa.

13. Describe the major anatomical sites of portosystemic anastomosis, listing the veins involved.

14. Define genetic code. What are the salient features of genetic code?

    5 marks

15. What are posttranslational modifications? Discuss in brief the post- translational modifications involving various amino acids.

16. Describe any two methods to measure cardiac output. Explain the role of Frank-Starling law' in cardiac contraction.

17. Discuss the structure and function of Golgi tendon organ.

    5 marks

18. Describe the cerebrospinal fluid (CSF) flow from site of production to its absorption. Write a note on the mechanism of its absorption.

    5 marks

19. A 62-year-old hypertensive male is brought to medical OPD with the complaints of sudden onset of visual loss in both his eyes. His ophthalmologic examination reveals right homonymous hemianopia with macular sparing, and his MR scan shows cerebral hemorrhage involving left occipital lobe. Based on the above findings, explain the anatomical basis of visual loss in this patient using a diagram depicting the entire visual pathway.

20. Define glomerular filtration rate (GFR). Discuss the different clearance tests used to measure glomerular filtration rate.

21. Discuss briefly the different steps of polymerase chain reaction (PCR) technique. Write three applications of PCR technique.in clinical medicine.

22. Discuss in brief the functional divisions of cerebellum and state the role of each division.

    5 marks

23. Discuss in brief the medial and lateral descending pathways and their functions.

    5 marks

24. Discuss in brief the role of oxytocin in parturition and lactation.

    5 marks

25. State the therapeutic indications, drug interactions and side effects of Methotrexate.

    5 marks

26. State the therapeutic indications, drug interactions and side effects of Furosemide.

    5 marks

27. Enumerate any four 'antigen-presenting cells (APCs)'. Describe in brief two major antigen processing pathways.

    5 marks

28. Enumerate any two types of effector T cells. What are Treg cells?

29. A 6-year-old boy presented with fever, chills and malaise. On history, he revealed intense throbbing pain around the right knee. X-ray of the knee revealed a lytic focus of bone destruction surrounded by a zone of sclerosis. () What is the most probable diagnosis? (ti) Describe the pathogenesis of this condition. (iti) Enumerate four complications.

30. Describe the laboratory diagnosis and immunophenotypic classification of acute lymphoblastic leukaemia.

31. Classify 'thermal injuries'. How is the total body surface area involved in burns calculated in adults? Give the various causes of death in burns.

32. Define inflammation. Describe the cardinal features of acute inflammation.

33. Describe the pathogenesis of secondary tuberculosis. Enumerate five microscopic features of tuberculosis in AIDS.

34. Elaborate the mechanism of action of antimicrobial resistance.

    5 marks

35. Name the third-generation Cephalosporins. State their therapeutic indications and side effects.

    5 marks

36. Name five clinically important species of Candida.

37. Write the laboratory diagnosis of Candida infection.

38. Mention a seromarker for invasive candidiasis.

39. Describe in brief any five clinical manifestations of Aspergillus infection. Mention one specific antigen test used for its diagnosis.

40. Classify neurotoxic poisons. Discuss in brief the clinical features, treatment and postmortem findings in acute poisoning by 'opiates'.

41. Write a brief note on 'atypical drowning'.

    5 marks

42. A 60-year-old male presented with an irregular plaque-like lesion at the base of tongue. Biopsy showed a proliferation of atypical cells displaying keratin pearls. l. What is the most probable diagnosis? 2. Describe the pathogenesis of this condition.

43. Enumerate five differences between benign and malignant tumours. Describe the mechanisms by which the tumour cells evade the immune system.

44. Briefly describe the advantages of Liposomal Amphotericin-B over conventional Amphotericin-B.

    5 marks

45. Briefly describe the therapeutic indications and adverse effects of Thiazides.

46. Elaborate the therapeutic indications, mechanism of action and side effects of Metformin.

    5 marks

47. Enumerate five agents of malaria in humans.

48. Describe in brief rapid diagnostic test (RDT) used for malaria and its advantages.

49. Mention the vaccine available for malaria.

50. Discuss the role of 'antibody-dependent enhancement' in pathogenesis of severe dengue. Write in brief the laboratory diagnosis of dengue.

51. Define injury as per Bharatiya Nyaya Sanhita. Enumerate the various ' mechanical injuries. Write a brief note on 'concealed punctured wound'.

52. What is identification? Describe in brief the primary and secondary characteristics of identification. Which is the surest test for identification of an individual?

53. Discuss the management of complicated Plasmodium falciparum malaria.

    5 marks

54. Describe the therapeutic indications and side effects of Primaquine.