Q25. A patient presents with hypoglycemia, hepatomegaly, and muscle weakness. Fasting plasma free fatty acids and ketones are low. This suggests a defect in:
A) Carnitine shuttle
B) HMG-CoA lyase
C) Lipoprotein lipase
D) Acyl-CoA dehydrogenase
E) Acetyl-CoA carboxylase
Q26. Which lipoprotein is most elevated in familial hypercholesterolemia (defective LDL receptor)?
A) Chylomicrons
B) VLDL
C) IDL
D) LDL
E) HDL
Q27. During prolonged fasting, the liver produces ketone bodies from:
A) Glucose
B) Acetyl-CoA derived from β-oxidation
C) Lactate
D) Amino acids only
E) Glycerol
Q28. (True/False) Acetyl-CoA carboxylase is activated by palmitoyl-CoA. qcm biochimie 1ere annee medecine exclusive
Q29. Statins lower cholesterol by inhibiting:
A) HMG-CoA synthase
B) HMG-CoA reductase
C) Acyl-CoA cholesterol acyltransferase (ACAT)
D) Cholesterol ester transfer protein (CETP)
E) LDL oxidation
Q30. The rate-limiting step in fatty acid synthesis is catalyzed by:
A) Fatty acid synthase
B) Acetyl-CoA carboxylase
C) Carnitine palmitoyltransferase I
D) Malonyl-CoA decarboxylase
E) Thiolase
Question: A. The Krebs cycle takes place in the mitochondrial matrix. B. Acetyl-CoA enters the cycle and condenses with Oxaloacetate to form Citrate. C. One turn of the cycle produces 3 NADH, 1 $FADH_2$, and 1 GTP. D. $CO_2$ is produced during the cycle. E. The cycle is anabolic only. Question: A
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Question: Concerning glucose ($C_6H_12O_6$), which of the following statements are TRUE? A. In aqueous solution, glucose exists exclusively in an open-chain form. B. D-Glucose and L-Glucose are enantiomers. C. The cyclic form of glucose results from the reaction between the $C_5$ hydroxyl group and the $C_1$ aldehyde group. D. $\alpha$-D-glucose and $\beta$-D-glucose are diastereoisomers. E. Glucose is a ketose.
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QCM Type : Parmi les énoncés suivants concernant la structure quaternaire, combien sont exacts ?
C'est le chapitre où les étudiants perdent le plus de points. Un QCM exclusif teste la représentation graphique.
Subject: Core Biochemistry Fundamentals Target: 1st Year Medical Students (PCEM1) Format: QCM Type "K" (Multiple True/False) or Single Best Answer, categorized by module. categorized by module.
Question: A. Gluconeogenesis is the synthesis of glucose from non-carbohydrate precursors. B. It occurs entirely in the cytoplasm. C. Pyruvate Carboxylase is a key enzyme requiring Biotin. D. Fructose-1,6-bisphosphatase bypasses the irreversible step of PFK-1. E. High levels of ATP stimulate gluconeogenesis.
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