CBSE EXAM QUESTIONS WITH CORRECT ANSWERS 2026

CBSE EXAM QUESTIONS WITH CORRECT kk kk kk kk




ANSWERS 2025/2026 kk kk




Alkaptonuria - CORRECT ANSWER -Absence of homogentisate oxidase
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- arthritis

- discolored sclerae and other areas (ear cartilage)kk kk kk kk kk kk




- Dark urine kk




- spinal disc degeneration and dense calcifications possible
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What is the cause of "bitter almond" breath? - CORRECT ANSWER -Cyanide poisoning
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What does cyanide inhibit? - CORRECT ANSWER -Cytocrhome oxidase in the ETC
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What is the treatment for cyanide poisoning? - CORRECT ANSWER -Amyl nitrate (oxidizes hemoglobin
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to methemoglobin, which strongly binds cyanide)
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6 month old child with frequent infections and carpopedal spasm and facial spasm upon tapping
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- CORRECT ANSWER -DiGeorge Syndrome kk kk kk




- hypoparathyroidism and T-cell deficiency kk kk kk




Hypocalcemia is what causes the spasms kk kk kk kk kk




CATCH22 pneumonic: Chromosome 22, Abnormal facies, Thymic hypoplasia, Cleft palate, and
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Hypocalcemia
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,Young (27 yrs old) man with lots of atherosclerotic plaques and small, raised yellow-brown
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lesions on extensor surfaces of arms - CORRECT ANSWER -Familial hypercholesterolemia (FH)
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Inherited disorder that causes high serum cholesterol levels
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the lesions are xanthomas caused by deposits of the cholesterol
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A baby is born with severe abnormalities, including prominent epicanthal folds, up slanting
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palpebral fissures, and macroglossia. He also has thick skin at the nape of the neck
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He vomits greenish material immediately after eating - CORRECT ANSWER -Down Syndrome
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The vomiting is due to GI disorder which they often have
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Boy is born with flat feet, long face, large ears, and an abnormal appearing X-chromosome - CORRECT
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ANSWER -Fragile X syndrome
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Expansion of a CGC trinucleotide repeat sequence on the X chromosome
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X-linked genetic kk




The most common cause of mental retardation is - CORRECT ANSWER -Fragile X syndrome
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A baby begins to get sick after weaning from breast milk, and has a low glucose level which is not
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lost in urine - CORRECT ANSWER -Fructose intolerance
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Fructose-1-phosphate levels will be elevated in liver cells kk kk kk kk kk kk kk

, A 12 year old intellectually disabled boy presents with vision difficulties. Exam reveals bilateral
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dislocated lenses and a tall, thin body habitus. Labs show increased levels of serum methionine
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and serum homocysteine - CORRECT ANSWER -Homocysteinuria caused by cystathionine
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synthase
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Also at risk for CV disease and osteoporosis
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HOMOCY



Homocyteine in urine, osteoporosis, marfoid habitus, ocular changes, kYphosis kk kk kk kk kk kk kk kk




Can also be intellectually disabled
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1 year old presents with abnormalities. PE reveals developmental delay, coarse facial features,
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skeletal abnormalities, umbilical hernia, corneal clouding. Baby's liver and spleen are enlarged,
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and the joints are stiff - CORRECT ANSWER -Hurler Syndrome
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One of the mucopolysaccharidoses diseases
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Caused by alpha L-iduronidase defect (can't break down dermatin sulfate and heparan sulfate -
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accumulates in tissues)
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Hunter's Syndrome vs Hurler's Syndrome - CORRECT ANSWER -Hunters = mild Hurler's +
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aggressive behavior, no corneal clouding
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2 year old with mental retardation and restricted joint movement. PE reveals coarse facial
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features and clouded corneas. Blood tests reveal elevated lysosomal enzymes in the serum.
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Parents are first cousins - CORRECT ANSWER -I-cell disease
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