Description : The rate limiting step in cholesterol biosynthesis is one of the followings : (A) LDL-receptor concentration (B) VLDL secretion (C) Mevalonic acid formation (D) Co-enzyme A formation
Last Answer : (C) Mevalonic acid formation
Description : Enzymes responsible for ketone body formation are associated mainly with the (A) Mitochondria (B) Endoplasmic reticulum (C) Nucleus (D) Golgi apparatus
Last Answer : Answer : A
Description : A pathway that requires NADPH as a cofactor is (A) Extramitochondrial folic acid synthesis (B) Ketone body formation (C) Glycogenesis (D) Gluconeogenesis
Description : The rate limiting step in catecholamine synthesis is catalysed by (A) Phenylalanine hydroxylase (B) Tyrosine hydroxylase (C) Dopa decarboxylase (D) Phenylethanolamine N-methyl transferase
Last Answer : Answer : B
Description : In the biosynthesis of testosterone the rate limiting step is conversion of (A) Cholesterol to pregnenolone (B) Pregnenolone to progesterone (C) Progesterone to 17 α-hydroxy progesterone (D) 17 α-Hydroxy progesterone to androstenedione
Description : The principal rate limiting step in the biosynthesis of bile acids is at the (A) 7-Hydroxylase reaction (B) 12 α-Hydroxylase reaction (C) Conjugation reaction (D) Deconjugation reaction
Description : The rate limiting reaction in the lipogenic pathway is (A) Acetyl-CoA carboxylase step (B) Ketoacyl synthase step (C) Ketoacyl reductase step (D) Hydratase step
Description : The rate limiting step in the biosynthesis of catecholamines is (A) Decarboxylation of dihydroxyphenylalanine (B) Hydroxylation of phenylalanine (C) Hydroxylation of tyrosine (D) Oxidation of dopamine
Last Answer : Answer : C
Description : What is the rate-limiting-step in the cholesterol biosynthesis?
Last Answer : HMG CoA reductase.
Description : All the following correctly describe the intermediate 3-OH-3-methyl glutaryl CoA except (A) It is generated enzymatically in the mitochondrial matrix (B) It is formed in the cytoplasm (C) It inhibits the first step in cholesterol synthesis (D) It is involved in the synthesis of ketone bodies
Description : A pathway that requires NADPH as a cofactor is (A) Fatty acid oxidation (B) Extra mitochondrial denovo fatty acid synthesis (C) Ketone bodies formation (D) Glycogenesis
Description : The rage limiting step cholesterol biosynthesis is (A) Squalene synthetase (B) Mevalonate kinase (C) HMG CoA synthetase (D) HMG CoA reductase
Last Answer : Answer : D
Description : Choose the correct statement about lovastatin: A. It markedly lowers plasma triglyceride with little effect on cholesterol level B. It is used as an adjuvant to gemfibrozil for type III ... hypercholesterolemia D. It is a competitive inhibitor of the rate limiting step in cholesterol synthesis
Last Answer : D. It is a competitive inhibitor of the rate limiting step in cholesterol synthesis
Description : Ketone body utilisation is taking place in which organs?
Last Answer : Ketolysis is taking place in extra hepatic tissues. (All other tissues, except liver).
Description : For Catecholamine biosynthesis the rate limiting enzyme is (A) DOPA decarboxylase (B) DOPAMINE β-hydroxylase (C) Tyrosine hydroxylase (D) Phenylalanine hydroxylase
Description : In the biosynthesis of cholesterol, the rate limiting enzyme is (A) Mevalonate kinase (B) HMG-CoA synthetase (C) HMG-CoA reductase (D) Cis-prenyl transferase
Description : If all the enzymes, intermediates and cofactors of the citric acid cycle as well as an excess of the starting substrate acetylCoA are present and functional in an organelle free solution at the appropriate ... oxygen (B) Half life of enzyme (C) Turnover of intermediates (D) Reduction of cofactors
Description : The reaction catalysed by phosphofructokinase (A) Is activated by high concentrations of ATP and citrate (B) Uses fruitose-1-phosphate as substrate (C) Is the rate-limiting reaction of the glycolytic pathway (D) Is inhibited by fructose 2, 6-bisphosphate
Last Answer : C
Description : Which one of the following is a rate limiting enzyme of gluconeogenesis? (A) Hexokinase (B) Phsophofructokinase (C) Pyruvate carboxylase (D) Pyruvate kinase
Description : The 4 rate limiting enzymes of gluconeogenesis are (A) Glucokinase, Pyruvate carboxylae phosphoenol pyruvate carboxykinase and glucose-6-phosphatase (B) Pyruvate carboxylase, phosphoenol ... fructokinase, pyruvate carboxylase, phosphoenol pyruvate carboxykinase and fructose 1, 6 diphosphatase
Last Answer : B
Description : What is the rate limiting enzyme of de novo synthesis of fatty acid?
Last Answer : Acetyl CoA carboxylase.
Description : The formation of a peptide bond during the elongation step of protein synthesis results in the splitting of how many high energy bonds? (A) 1 (B) 2 (C) 3 (D) 4
Description : The initial step of the citric acid cycle is (A) Conversion of pyruvate to acetyl-CoA (B) Condensation of acetyl-CoA with oxaloacetate (C) Conversion of citrate to isocitrate (D) Formation of α -ketoglutarate catalysed by isocitrate dehydrogenase
Description : The ‘Committed step’ in the biosynthesis of cholesterol from acetyl CoA is (A) Formation of acetoacetyl CoA from acetyl CoA (B) Formation of mevalonate from HMG CoA (C) Formation of HMG CoA from acetyl CoA and acetoacetyl CoA (D) Formation of squalene by squalene synthetase
Description : Acetyl CoA required for de novo synthesis of fatty acids is obtained from (A) Breakdown of existing fatty acids (B) Ketone bodies (C) Acetate (D) Pyruvate
Description : Acetyl-CoA can be formed from (A) Pyruvate (B) Fatty acids (C) ketone bodies (D) All of these
Description : Ketone bodies serve as a fuel for (A) Extrahepatic tissues (B) Hepatic tissues (C) Erythrocytes (D) Mitochondria
Description : The structure which appears to be the only organ to add significant quantities of ketone bodies to the blood is (A) Brain (B) Erythrocytes (C) Liver (D) Skeletal muscle
Description : In humans under normal conditions loss of ketone bodies via urine is usually less than (A) 1 mg/24 hr (B) 4 mg/24 hr (C) 8 mg/24 hr (D) 10 mg/24 hr
Description : The concentration of ketone bodies in the blood does not normally exceed (A) 0.2 mmol/L (B) 0.4 mmol/L (C) 1 mmol/L (D) 2 mmol/L
Description : All the following statements correctly describe ketone bodies except (A) They may result from starvation (B) They are present at high levels in uncontrolled diabetes (C) They include—OH β-butyrate and acetone (D) They are utilized by the liver during long term starvation
Description : Which of the following products of triacylglycerol breakdown and subsequent β-Oxidation may undergo gluconeogenesis? (A) Acetyl CoA (B) Porpionyl CoA (C) All ketone bodies (D) Some amino acids
Description : All the following statements regarding ketone bodies are true except (A) They may result from starvation (B) They are formed in kidneys (C) They include acetoacetic acid and acetone (D) They may be excreted in urine
Description : Ketone bodies are synthesized from fatty acid oxidation products by which of the following organs? (A) Liver (B) Skeletal muscles (C) Kidney (D) Brain
Description : All of the following tissue are capable of using ketone bodies except (A) Brain (B) Renal cortex (C) R.B.C. (D) Cardiac muscle
Description : The acetyl CoA formed on β-oxidation of all long chain fatty acids is metabolized under normal circumstances to (A) CO2 and water (B) Cholesterol (C) Fatty acids (D) Ketone bodies
Description : Ketone bodies are formed in (A) Kidney (B) Liver (C) Heart (D) Intestines
Description : All the following statements about ketone bodies are true except (A) Their synthesis increases in diabetes mellitus (B) They are synthesized in mitchondria (C) They can deplete the alkali reserve (D) They can be oxidized in the liver
Description : Ketone bodies are synthesized in (A) Adipose tissue (B) Liver (C) Muscles (D) Brain
Description : An enzyme required for the synthesis of ketone bodies as well as cholesterol is (A) Acetyl CoA carboxylase (B) HMG CoA synthetase (C) HMG CoA reductase (D) HMG CoA lyase
Description : In human and other ureotelic organisms, the end product of amino acid nitrogen metabolism: (A) Bile acids (B) Ketone bodies (C) Urea (D) Barium sulphate
Description : During starvation, ketone bodies are used as a fuel by (A) Erythrocytes (B) Brain (C) Liver (D) All of these
Description : What test is used to identify ketone bodies in urine?
Last Answer : Rotheraís test.
Description : Utilisation of ketone bodies by peripheral tissues needs which enzyme?
Last Answer : Succinyl CoA dependent thiophorase.
Description : Ketone bodies are formed in which tissue?
Last Answer : Liver.
Description : What are ketone bodies?
Last Answer : Aceto acetate, beta hydroxy butyric acid, and acetone.
Description : Which disaccharide has no free aldehyde or ketone group?
Last Answer : Sucrose.
Description : Which of the following is not a correct statement about the electrophilic substitution mechanism of benzene? (a) Benzene functions as a nucleophile. (b) Formation of a carbocation intermediate is the ... hybridized carbon in the ring. (d) The addition product is a frequently observed minor product.
Last Answer : The addition product is a frequently observed minor product.
Description : The amino acids present in pulses can supplement the limiting amino acids of (A) Cereals (B) Milk (C) Fish (D) Nuts and beans
Description : The limiting amino acid in pulses is (A) Leucine (B) Lysine (C) Tryptophan (D) Methionine