9 Previous Year Questions with Answers & Explanations
A child presents with a history of fractures, multiple petechiae, perifollicular hemorrhages, and gum bleeding. Which of the following enzyme defects is involved?
A patient has elevated phenylalanine levels (40 mg/dL), but phenylalanine hydroxylase enzyme levels are normal. Which cofactor deficiency is most likely responsible for this condition?
A man is trapped in a tunnel for 5 consecutive days without access to food but survives. What is the primary source of energy for his brain during this period?
A patient presents with anemia, positive Romberg sign, and other neurological findings suggestive of vitamin B12 deficiency. Laboratory findings show elevated homocysteine levels. Which amino acid is likely to be deficient in this patient?
A neonate presents with seizures and is found to have a cherry red spot on fundus examination. Enzyme assay reveals deficiency of hexosaminidase A. Which of the following substances is most likely to be accumulated in this patient?
A frameshift mutation occurs due to the insertion of a new nucleotide at the 4th position of an mRNA sequence with 900 nucleotides. What is the most likely outcome of this mutation?
A patient presents with skin cancer and hyperpigmentation that worsens with sunlight exposure. Which of the following DNA repair mechanisms is most likely defective in this condition?
Which of the following is a mitochondrial inheritance disorder?
A child presents with developmental delay and coarse facial features. Enzyme assay reveals a deficiency of α-L-iduronidase. Which of the following substances is most likely to accumulate in this condition?