Q20.Which process enables skin to synthesise vitamin D naturally?
(a) Drinking chlorinated water
(b) Exposure to ultraviolet-B radiation
(c) Absorbing infrared heat alone
(d) Exposure to loud sound
Answer: (b) Exposure to ultraviolet-B radiation
Explanation: UV-B radiation converts a cholesterol-derived precursor in the skin into vitamin D3. Diet and supplements are alternative sources. Appropriate sunlight advice depends on skin type, location and skin-cancer risk. The surrounding dietary pattern and nutrient absorption can also influence deficiency risk.
Q19.Itai-itai disease in Japan is historically linked with contamination by which heavy metal?
(a) Cadmium
(b) Mercury
(c) Zinc
(d) Magnesium
Answer: (a) Cadmium
Explanation: Itai-itai disease was associated with chronic cadmium pollution in Japan. Cadmium can damage kidneys and disrupt bone mineral metabolism, leading to severe bone pain, fragility and fractures. Exposure history and examination are important for distinguishing related conditions.
Q18.Epidemic dropsy has been associated with adulteration of edible oils by what?
(a) Vitamin D
(b) Coconut water
(c) Pure mustard seed
(d) Argemone oil
Answer: (d) Argemone oil
Explanation: Epidemic dropsy results from toxic alkaloids, including sanguinarine, found in Argemone mexicana oil used to adulterate edible oil. It may cause oedema and systemic toxicity; food quality control is essential. Prevention depends on identifying the underlying behavioural or environmental risk.
Q17.Which plant is a recognised source of toxic oil involved in epidemic dropsy?
(a) Pisum sativum
(b) Ocimum tenuiflorum
(c) Argemone mexicana
(d) Triticum aestivum
Answer: (c) Argemone mexicana
Explanation: Argemone mexicana, also called Mexican prickly poppy, contains toxic alkaloids in its seeds. Adulteration of edible oil with argemone seed oil has caused outbreaks of epidemic dropsy. Clinical context helps separate similar symptoms produced by very different causes.
Q16.Gout is caused by deposition of crystals of which compound in joints?
(a) Calcium chloride
(b) Monosodium urate
(c) Glucose
(d) Sodium bicarbonate
Answer: (b) Monosodium urate
Explanation: Gout involves inflammatory reactions to monosodium urate crystals within joints and tissues. Attacks typically produce sudden severe pain, redness and swelling; long-term urate-lowering therapy may be indicated. Some inflammatory conditions can cause long-term damage if treatment is delayed.
Q15.Which joint is classically affected in a first episode of gout?
(a) First metatarsophalangeal joint of big toe
(b) Shoulder only
(c) Elbow only
(d) Jaw joint only
Answer: (a) First metatarsophalangeal joint of big toe
Explanation: An acute attack of gout often affects the base of the big toe, a presentation known as podagra. However, ankles, knees and other joints can also be involved. A precise diagnosis matters because different forms of arthritis need different treatments.
Q14.Tophi are associated with which chronic joint disease?
(a) Emphysema
(b) Rickets
(c) Scurvy
(d) Gout
Answer: (d) Gout
Explanation: Tophi are deposits of monosodium urate crystals found in some people with longstanding gout. They may appear around joints, ear cartilage and other tissues and indicate substantial urate burden. Joint swelling alone does not reveal the cause without appropriate clinical assessment.
Q13.Which diet-related factor can increase gout risk in susceptible individuals?
(a) Balanced vegetable intake
(b) Normal physical activity
(c) Heavy alcohol intake
(d) Adequate hydration
Answer: (c) Heavy alcohol intake
Explanation: Alcohol, especially heavy consumption, can increase serum urate and trigger gout attacks in susceptible people. Genetic factors, kidney function, certain medications and some dietary patterns also influence risk. Some inflammatory conditions can cause long-term damage if treatment is delayed.
Q12.Rheumatoid arthritis is most accurately described as which condition?
(a) Vitamin C deficiency
(b) Autoimmune inflammatory joint disease
(c) Disease caused only by excess uric acid
(d) Lung disease from silica
Answer: (b) Autoimmune inflammatory joint disease
Explanation: Rheumatoid arthritis is an autoimmune disorder causing persistent inflammation of joints, often symmetrically in hands and wrists. Untreated disease can lead to damage and disability; it differs from gout. A precise diagnosis matters because different forms of arthritis need different treatments.
Q11.Which statement about arthritis is correct?
(a) It refers broadly to disorders involving joint inflammation or disease
(b) It only affects children
(c) It always has an infectious cause
(d) It is always caused by uric acid
Answer: (a) It refers broadly to disorders involving joint inflammation or disease
Explanation: Arthritis is an umbrella term for many joint disorders. Gout, rheumatoid arthritis, osteoarthritis and infections have different mechanisms. Uric-acid crystal deposition specifically characterises gout, not every type of arthritis. Joint swelling alone does not reveal the cause without appropriate clinical assessment.
