Description : Competitive inhibitors (A) Decrease the Km (B) Decrease the Vmax (C) Increase the Km (D) Increase the Vmax
Last Answer : Answer : C
Description : In non-competitive enzyme action (A) Vmax is increased (B) Apparent km is increased (C) Apparent km is decreased (D) Concentration of active enzyme molecule is reduced
Description : In reversible non-competitive enzyme activity inhibition (A) Vmax is increased (B) Km is increased (C) Km is decreased (D) Concentration of active enzyme is reduced
Last Answer : Answer : D
Description : A competitive inhibitor of an enzyme (A) Increases Km without affecting Vmax (B) Decreases Km without affecting Vmax (C) Increases Vmax without affecting Km (D) Decreases both Vmax and Km
Last Answer : Answer : A
Description : In competitive inhibition of enzyme action (A) The apparent Km is decreased (B) The apparent Km is increased (C) Vmax is decreased (D) Apparent concentration of enzyme molecules decreased
Last Answer : Answer : B
Description : A competitive inhibitor of an enzyme has which of the following properties? (A) It is frequently a feedback inhibitor (B) It becomes covalently attached to an enzyme (C) It decreases the Vmax (D) It interferes with substrate binding to the enzyme
Description : In competitive enzyme activity inhibition (A) Apparent Km is decreased (B) Apparent Km is increased (C) Vmax is increased (D) Vmax is decreased
Description : In competitive enzyme activity inhibition (A) The structure of inhibitor generally resembles that of the substrate (B) Inhibitor decreases apparent Km (C) Km remains unaffective (E) Inhibitor decreases Vmax without affecting Km
Description : The kinetic effect of purely competitive inhibitor of an enzyme (A) Increases Km without affecting Vmax (B) Decreases Km without affecting Vmax (C) Increases Vmax without affecting Km (D) Decreases Vmax without affecting Km
Description : The Michaelis constant, Km is (A) Numerically equal to ½ Vmax (B) Dependent on the enzyme concentration (C) Independent of pH (D) Numerically equal to the substrate concentration that gives half maximal velocity
Description : If the substrate concentration is much below the km of the enzyme, the velocity of the reaction is (A) Directly proportional to substrate concentration (B) Not affected by enzyme concentration (C) Nearly equal to Vmax (D) Inversely proportional to substrate concentration
Description : Which one of the following statements regarding enzyme inhibition is correct? (a) Competitive inhibition is seen when a substrate competes with an enzyme for binding to an inhibitor protein. (b ... large amount of substrate. (d) Non-competitive inhibitors often bind to the enzyme irreversibly.
Last Answer : (b) Competitive inhibition is seen when the substrate and the inhibitor compete for the active site on the enzyme
Description : The presence of a non competitive inhibitor (A) Leads to both an increase in the Vmax of a reaction and an increase in Km (B) Leads to a decrease in the observed Vmax (C) Leads to a decrease in Km and Vmax (D) Leads to an increase in Km without affecting Vmax
Description : Which of the following statements about an enzyme exhibiting allosteric kinetics with cooperative interaction is false? (A) A plot of V-Vk [s] has a sigmaidal shape (B) An inhibitor may increase the ... Km and Vmax (D) Removal of allosteric inhibitor may result in hyperbolic V-S [s] plot
Description : In competitive inhibition which of the following kinetic effect is true ? (A) Decreases both Km and Vmax (B) Increases both Km and Vmax (C) Decreases Km without affecting Vmax (D) Increases Km without affecting Vmax
Description : Km value of enzyme is substrate concentration at (A) ½ Vmax (B) 2 Vmax (C) ½ Vmax (D) 4 Vmax
Description : The rate of an enzyme catalyzed reaction was measured using several substrate concentrations that were much lower than Km, the dependence of reaction velocity on substrate concentration can best be ... constant fraction of Vmax (C) Equal to Km (D) Proportional to the substrate concentration
Description : When [s] is equal to Km, which of the following conditions exist? (A) Half the enzyme molecules are bound to substrate (B) The velocity of the reaction is equal to Vmax (C) The velocity of the reaction is independent of substrate concentration (D) Enzyme is completely saturated with substrate
Description : In enzyme kinetics Km implies (A) The substrate concentration that gives one half Vmax (B) The dissocation constant for the enzyme substrate comples (C) Concentration of enzyme (D) Half of the substrate concentration required to achieve Vmax
Description : In enzyme kinetics Vmax reflects (A) The amount of an active enzyme (B) Substrate concentration (C) Half the substrate concentration (D) Enzyme substrate complex
Description : Difference between competitive inhibitors and non-competitive inhibitors? -Biology
Last Answer : answer:
Description : Do non competitive inhibitors bind to the active site?
Last Answer : Feel Free to Answer
Description : Pick out the wrong statement. (A) Catalytic activity of enzyme catalysed reactions which is affected by temperature, pH value & chemical agents, is maximum at a temperature of about 45°C ... in enzyme catalysed reactions can be calculated by using the thermodynamic properties of substrates & prod
Last Answer : (C) Enzymes help in increasing the activation energy of the reaction
Description : Which inactivates an enzyme by occupying its active site? (A) Competitive inhibitor (B) Allosteric inhibitor (C) Non-competitive inhibitor (D) All of these
Description : Enzyme inhibition caused by a substance resembling substrate molecule is (A) Competitive inhibition (B) Non-competitive inhibition (C) Feedback inhibition (D) Allosteric inhibition
Description : Which one of the following regulatory actions involves a reversible covalent modification of the enzyme? (A) Phosphorylation of ser-OH on the enzyme (B) Allosteric modulation (C) Competitive inhibition (D) Non-competitive inhibition
Description : Which of the following regulatory reactions involves a reversible covalent modification of an enzyme? (A) Phosphorylation of serine OH on the enzyme (B) Allosteric modulation (C) Competitive inhibition (D) Non-competitive inhibition
Description : In non competitive enzyme activity inhibition, inhibitor (A) Increases Km (B) Decreases Km (C) Does not effect Km (D) Increases Km
Description : In reversible non-competitive enzyme activity inhibition (A) Inhibitor bears structural resemblance to substrate (B) Inhibitor lowers the maximum velocity attainable with a given amount of enzyme (C) Km is increased (D) Km is decreased
Description : Clinical significance of competitive inhibitors -Biology
Description : Contrast and compare competitive inhibitors with noncompetitive inhibitors. Which can be overcome by the addition of more substrate?
Last Answer : Competitive inhibitors reduce the productivity of enzymes by blocking substrates from entering active sites. This inhibition is what can be overcome by the addition of more substrate. Noncompetitive ... active site will become less and less effective at helping convert substrate to product.
Description : Choose the correct statement about allopurinol: A. It is a purine antimetabolite with antineoplastic activity B. It is a competitive inhibitor of xanthine oxidase C. It is inactive itself ... D. Both allopurinol as well as its metabolite alloxanthine are noncompetitive inhibitors of xanthine oxidase
Last Answer : B. It is a competitive inhibitor of xanthine oxidase
Description : Enzymes activity is controlled by (A) pH of the solution (B) Temperature (C) Concentration of the enzyme (D) Concentration of the substrate (E) All of these
Description : In enzyme assays, all the following are kept constant except (A) Substrate concentration (B) Enzyme concentration (C) pH (D) Temperature
Description : Factors affecting enzyme activity: (A) Concentration (B) pH (C) Temperature (D) All of these
Description : What are enzyme inhibitors? -Biology
Description : Which of the following statements about hypertension in diabetes patients is/are correct? A. Hypertension worsens the macrovascular disease of diabetes patients. B. Hypertension accelerates the ... single-drug therapy, are not indicated in the treatment of hypertension in diabetes patients.
Last Answer : Answer: ABCDE DISCUSSION: All of the answers listed are correct. By damaging endothelial cells, hypertension worsens macrovascular disease in all patients but especially in diabetics. Hypertension ... is not indicated because the chronic state of dehydration in such patients may become worse
Description : At the adrenergic synapse, the concentration of adrenaline in synaptic cleft: a. increased by cocaine which inhibit reuptake of adrenaline b. decreased by MAO (monoamine oxidase) - inhibitors c. controlled chiefly by the activity of the enzyme COMT d. increased by noradrenaline receptor blockers
Last Answer : increased by cocaine which inhibit reuptake of adrenaline
Description : Angiotensin converting enzyme inhibitors are contraindicated in: A. High renin hypertensives B. Diabetics C. Congestive heart failure patients D. Pregnant women
Last Answer : D. Pregnant women
Description : Clinically, the angiotensin antagonists share the following features of angiotensin converting enzyme inhibitors except: A. Antihypertensive efficacy B. Potential to reverse left ventricular hypertrophy ... of effect on carbohydrate tolerance D. Potential to induce cough in susceptible individuals
Last Answer : D. Potential to induce cough in susceptible individuals
Description : Which of the following statements most closely describes the current status of angiotensin converting enzyme inhibitors in congestive heart failure: A. They are the first choice drugs unless contraindicated B. ... substitute for digitalis D. They are to be used as adjuncts only in resistant cases
Last Answer : D. They are to be used as adjuncts only in resistant cases
Description : Angiotensin converting enzyme inhibitors afford maximum protection against progression of heart failure when used: A. At the higher therapeutic dose range over long term B. At the maximum tolerated dose only till ... restored C. At low doses over long term D. At low doses along with diuretics/digoxi
Last Answer : A. At the higher therapeutic dose range over long term
Description : Angiotensin converting enzyme inhibitors reduce the following haemodynamic parameters in congestive heart failure except: A. Systemic vascular resistance B. Right atrial pressure C. Cardiac output D. Heart rate × pressure product
Last Answer : C. Cardiac output
Description : Potentiation of bradykinin appears to play a role in the following effects of angiotensin converting enzyme inhibitors except: A. Fall in BP in the short term B. Fall in BP in the long term C. Cough in susceptible individuals D. Angioedema in susceptible individuals
Last Answer : B. Fall in BP in the long term
Description : Sildenafil is contraindicated in patients taking the following class of drugs: A. α-adrenergic blockers B. β-adrenergic blockers C. Organic nitrates D. Angiotensin converting enzyme inhibitors
Last Answer : C. Organic nitrates
Description : The following abnormality in PRPP synthetase can cause primary gout: (A) High Vmax (B) Low Km (C) Resistance to allosteric inihbition. (D) All of these
Description : In Lineweaver-Burk plot, the y-intercept represents (A) Vmax (B) Km (C) Km (D) 1/Km
Description : When the velocity of an enzymatic reaction equals Vmax, substrate concentration is (A) Half of Km (B) Equal to Km (C) Twice the Km (D) Far above the Km
Description : From the L ineweaver-Burk p lot of Michaelis-Menten equation, Km and Vmax can be determined when V is the reaction velocity at substrate concentration S, the X-axis experimental data are expressed as (A) 1/V (B) V (C) 1/S (D) S