PEDIGREE 2025 PG QUIZ

Hereditary orotic aciduria type II is due to deficiency of the following enzyme:

• Dihydroorotate dehydrogenase

• Orotate phosphoribosyl transferase

• Aspartate transcarbamoylase

• Orotidylate decarboxylase

A 5 month old infant presents with a seizure. His mother gave history of lethargy and irritability past several days. The infant is hypoglycemic and urine ketones are negative. Short chain dicarboxylic acids are elevated. The most likely enzyme deficiency is

• Carnitine Acyltransferase I

• Medium chain Acyl CoA Dehydrogenase

• Very Long Chain Acyl CoA Dehydrogenase

• Fatty Acyl CoA Synthase

1. Assertion: The Fatty Acid Synthase Complex & Acetyl-CoA Carboxylase Are Adaptive Enzymes

Reason: These enzymes adapt to the physiologic needs of the body by Covalent modification

• Both Assertion and Reason are true, and Reason is the correct explanation for Assertion

• Both Assertion and Reason are true, and Reason is not the correct explanation for assertion

• Assertion is true, but Reason is false

• Assertion is false, but Reason is true

A 50-year-old male patient has high cholesterol levels and is placed on lovastatin. He is counselled to stop drinking his usual glass of grapefruit juice every morning. Which of the following may be the correct reason for stopping grapefruit juice?

• Grapefruit juice inhibits the cytochrome p450 enzyme which modifies lovastatin for excretion.

• Grapefruit juice stimulates the cytochrome p450 enzyme which modifies lovastatin for excretion.

• Grapefruit juice is a competitive inhibitor of lovastatin binding to cholesterol.

• Grapefruit juice is a competitive inhibitor of HMG-CoA reductase.

Assertion: Low carbohydrate and high fat diets are commonly prescribed in weight reduction programs.

Reason: This type of diet is ketogenic indicating active fatty acid synthesis and gluconeogenesis for energy production

• Both Assertion and Reason are true, and Reason is the correct explanation for Assertion

• Both Assertion and Reason are true, and Reason is not the correct explanation for assertion

• Assertion is true, but Reason is false

• Assertion is false, but Reason is true

One of the following bonds is/are responsible for the semi rigidity of the Peptide bond

• α-Carbon (Cα) to the Carbonyl carbon (Co)

• Carbonyl carbon (Co) to the α-Nitrogen

• α-Carbon (Cα) to α-Nitrogen

• None of the above

All of the following is true about Methemoglobin except:

• Less than 1% of Hb is present as methemoglobin normally.

• It is Ferrihemoglobin

• does not transport O₂ but stores O₂

• congenital methemoglobinemia can be treated by large doses of ascorbate

All of the following are true about blood group antigens except:

• ABO blood group is determined by glycoproteins with O-linked oligosaccharides on the surface of RBCs.

• H substance formed by the action of a fucosyl transferase is Fucose—Gal—GluNAc—Protein

• Blood group A substance encodes a N-acetyl-galactosaminyl transferase that adds the terminal GalNAc to H substance

• Blood group B substance encodes a galactosyl transferase that adds the Gal residue to H substance.

All of the following are true about the action of Hexokinase except:

• has a K_m of 0.01mmol/L for glucose

• It provides glucose-6-phosphate at a constant rate to the liver

• Acts as a Glucose sensor in pancreatic β-islet cells

• Not induced by Insulin

True about Sugar alcohols being used as sweetening agents except

• less calorie content than ordinary sugar

• less likely to contribute to tooth decay

• only partially absorbed in the small intestine

• Prepared by oxidation of sugars