Biochemistry Part 1

The pH at which majority of amino acid exists in a form where it has an equal number of positive and negative charges and thus is electrically neutral is called the:

Glutathione is an important molecule for the clearance of free radicals in the body. It consists of only 3 amino acids. Which of the following polypeptides is the primary structure of glutathione?

Which of the following amino acid is incorrectly paired with its side chain?

A neonate, born at home, with no newborn care administered is rushed to the ER for heavy bleeding from the umbilical stump and recent onset generalized seizures. What vitamin deficiency is responsible for this?

What is the rate limiting enzyme of ketogenesis?

An infant present with hepatosplenomegaly and failure to A liver biopsy was done which revealed accumulation of polysaccharide with few branch points because of a deficiency for an important enzyme in carbohydrate metabolism. What is the diagnosis for this patient?

A patient who presented with mild jaundice had workup done, which revealed increased direct bilirubin, absent urine urobilinogen, (+) urine bilirubin. Liver biopsy showed liver hyperpigmentation. Which of the following is the most likely diagnosis?

If 20% of DNA consists of Guanosine nucleotides, how many percent are thymidine nucleotides?

Covalent modification is one of the most rapid ways of regulating enzyme activity in the cell. During fasting which of the following is expected to occur?

After a meal, insulin levels in the blood become elevated to effect which of the following changes in enzyme activity?

Which is the main source of NADPH for Lipogenesis?

Cyanide inhibits which of the following complex of the electron transport chain?

Which of the following is not an essential fatty acid?

Starch is a polymer of which of the following?

If the enthalpy change is negative and the entropy change is positive in a particular reaction, will this proceed spontaneously?

A 6-month-old infant presented with hyperacusis (exaggerated startle response), cherry red spot on the macula and froglike position. What substance is expected to accumulate in the brain?

Patient presents with arthritis and connective tissue pigmentation. On letting his urine stand, his urine is noted to darken. Which enzyme is deficient in this patient?

The following is ATP, Biotin and CO2 requiring:

Patient presents with urine smelling of maple syrup or burnt sugar and is diagnosed with maple syrup urine disease. Which of the following is not necessary for the function of the enzyme deficient in this disease?

Patient has an autosomal recessive genetic disease which makes him markedly susceptible to sunlight with subsequent formation of multiple skin cancers and premature death. The inherited defect involves repair of damaged DNA, particularly thymine Cells cultured from the patient has low activity of which of the following DNA repair mechanisms?