USMLE Content

Multiple-choice questions- Pentose phosphate pathway

1) Glucose breakdown in certain mammalian and bacterial cells can occur by mechanisms other than classic glycolysis. In most of these, glucose 6-phosphate is oxidized to 6- 6-phosphogluconate, which is then further metabolized by: a) an aldolase-type split to form glyceric acid and glyceraldehyde 3-phosphate. b) an aldolase-type split to form glycolic acid and erythrose […]

Multiple-choice questions- Pentose phosphate pathway Read More »

Gluconeogenesis- Multiple-choice questions

1)  A 4-month-old boy is being evaluated for seizures, psychomotor retardation, and hypotonia. Workup reveals elevated serum levels of lactate, alanine, pyruvate, and keto acids. Based on the clinical presentation, pyruvate carboxylase activity is measured using fibroblasts from a skin biopsy and is found to be markedly decreased. This enzyme is normally used to directly

Gluconeogenesis- Multiple-choice questions Read More »

Glycolysis- Multiple-choice questions (set-1)

1). A patient has chronic obstructive pulmonary disease, and enough oxygen is not reaching her tissues.  All of the following are expected except- a) The electron transport chain would be inhibited b) Glycolysis would be activated by a low ATP/ADP ratio c) More than normal amounts of ATP would be synthesized. d) Concentrations of NADH and

Glycolysis- Multiple-choice questions (set-1) Read More »

Amino Acid Metabolism-Multiple-choice questions (set-2)

Q.1- Which of the following is a common compound shared by the TCA and Urea cycles? a) α- Ketoglutarate b) Succinyl CoA c) Oxaloacetate d) Fumarate Q.2-Which of the following is a common nitrogen acceptor for all reactions involving transaminases? a) α- Ketoglutarate b) Pyruvate c) Oxaloacetate d) Acetoacetate Q.3- In a 55- year-old man

Amino Acid Metabolism-Multiple-choice questions (set-2) Read More »

Amino acid metabolism-Multiple-choice questions (set-1)

Q.1- A 12 -year-old boy develops convulsions. After running an Electroencephalogram(EEG), a neurologist determines that the child has epilepsy. He is started on benzodiazepine, which promotes the activity of GABA. GABA is derived from Glutamate by which of the following reactions? a) Transamination b) Decarboxylation c) Deamination d) Hydroxylation e) Dehydrogenation Q.2- A couple of

Amino acid metabolism-Multiple-choice questions (set-1) Read More »

Molecular Biology-Multiple-choice questions (set-2)

Q.1- Which statement best describes the ‘semi-conservative replication’ of DNA? A) In each replication cycle, only one of the two DNA strands is replicated B) In each replication cycle, one of the parental strands is conserved C) In each replication cycle, the daughter cells acquire either the parental stands or new stands D) Only half

Molecular Biology-Multiple-choice questions (set-2) Read More »

Molecular Biology- Multiple-choice questions (set-1)

Q.1- A critical enzyme used directly in the synthesis of dTMP (thymidine) is a) Carbamoyl phosphate b) Aspartate Transcarbamylase c) Dihydrooratase d) Thymidylate synthase Q.2- In which phase of the cell cycle does DNA replication occur? a) G0 b) G1 c) S d) G2 Q.3-A 10-month-old baby boy presents with steatorrhea, recurrent pulmonary infections, GI

Molecular Biology- Multiple-choice questions (set-1) Read More »

Lipid metabolism- Multiple Choice questions-set-2

1- All except one are true about gastric lipase- a)   Main preduodenal lipase b)   Hydrolyzes triglycerides containing short and medium-chain fatty acids c)   The primary site of hydrolysis is the sn-3ester linkage d)   Optimum pH is 6.0-7.0 2- Pancreatic juice does not contain which of the followings- a)   Bile salts b)   Phospholipase A2 c)   Lipase and colipase d)   Lipoprotein lipase 3- The dietary fats are

Lipid metabolism- Multiple Choice questions-set-2 Read More »

Lipids- Multiple-choice questions-set-3

1. Which of the following are the ketone bodies? a) Acetyl CoA and Propionyl CoA b) Lecithin and Lysolecithin c) Acetoacetate and Beta-hydroxybutyrate d) Pyruvate and lactate e) Succinyl CoA and succinate 2. The enzyme ‘Thiolase’ catalyzes the conversion of: a) 2 Acetyl CoA to Acetoacetyl CoA b) Acetyl CoA to Malonyl CoA c) Fatty

Lipids- Multiple-choice questions-set-3 Read More »

Fatty Acid Metabolism- Multiple-Choice Questions (Solved)-set-4

Q.1- Glucose can be converted to glycerol-3-P through which of the following intermediates? a) Glycerol b) Dihydroxyacetone phosphate c) Acetyl CoA d) Pyruvate e) Malate. Q.2- Which of the following supplies the 2 carbon units that are added to the elongation of the fatty acid chain? a) Acetyl CoA b) Malonyl CoA c) β- Keto

Fatty Acid Metabolism- Multiple-Choice Questions (Solved)-set-4 Read More »

×