Description : Which one of the following statements is not characteristic of allosteric enzymes? (A) They frequently catalyze a committed step early in a metabolic pathway (B) They are often composed of subunits (C) They follow Michaelis-Menten kinetics (D) They frequently show cooperativity for substrate binding
Last Answer : Answer : C
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
Description : A sigmoidal plot of substrate concentration ([S]) verses reaction velocity (V) may indicate (A) Michaelis-Menten kinetics (B) Co-operative binding (C) Competitive inhibition (D) Non-competitive inhibition
Last Answer : Answer : B
Description : Lineweaver – Burk double reciprocal plot is related to (A) Substrate concentration (B) Enzyme activity (C) Temperature (D) Both (A) and (B) ENZYMES 145
Last Answer : Answer : D
Description : ........................ studied the kinetics of enzyme catalysis. a. Arrhenius b. Rutherford c. Micheal Faraday d. Michaelis & Menten
Last Answer : d. Michaelis & Menten
Description : In Lineweaver-Burk plot, the y-intercept represents (A) Vmax (B) Km (C) Km (D) 1/Km
Description : Michaelis – Menten equation is used to explain the effect of substrate concentration on (A) Carbohydrate (B) Enzyme (C) Lipid (D) Protein
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 : What is Michaelis-Menten Theory ?
Last Answer : It is otherwise called enzyme-substrate complex theory. The enzyme combines with the substrate, to form an enzyme-substrate complex, which immediately breaks down to the enzyme and the product.
Description : What is Michaelis Menten constant? -Biology
Last Answer : answer:
Description : The Michaehis-Menten hypothesis: (A) Postulates the formation of an enzyme substrate complex (B) Enables us to calculate the isoelectric point of an enzyme (C) States that the ... independent of substrate concentration (D) States that the reaction rate is proportional to substrate concentration
Last Answer : Answer : A
Description : Substrate concentration at which an enzyme attains half its maximum velocity is (A) Threshold value (B) Michaelis-Menton constant (C) Concentration level (D) None of these
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 : Different isoenzymes of an enzyme have the same (A) Amino acid sequence (B) Michaelis constant (C) Catalytic activity (D) All of these
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 : What are the salient features of enzyme kinetics?
Last Answer : Enzymes lower activation energy. They increase the chemical reaction, but do not alter equilibrium of the reaction.
Description : Define Michaelis constant of an enzyme. -Biology
Description : An enzyme of pyrimidine nucleotide biosynthesis sensitive to allosteric regulation is (A) Aspartate transcarbamoylase (B) Dihydroorotase (C) Dihydroorotate dehydrogenase (D) Orotidylic acid decarboxylase
Description : An enzyme which acts as allosteric regulator and sensitive to both phosphate concentration and to the purine nucleotides is (A) PRPP synthetase (B) PRPP glutamyl midotransferase (C) HGPR Tase (D) Formyl transferase
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 : The shape of an enzyme and consequently its activity can be reversibly altered from moment to moment by (A) Heat (B) Amino acid substrate (C) Allosteric subunits (D) Sulfur substitutions
Description : In which of the following types of enzymes an inducer is not required? (A) Inhibited enzyme (B) Cooperative enzyme (C) Allosteric enzyme (D) Constitutive enzyme
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 : An allosteric enzyme influences the enzyme activity by (A) Competiting for the catalytic site with the substrate (B) Changing the specificity of the enzyme for the substrate (C) Changing the conformation ... binding to a site other than catalytic site (D) Changing the nature of the products formed
Description : Which of the following is an allosteric enzyme? (A) Phosphohexose isomerase (B) Phosphotriose isomerase (C) Lactate dehydrogenase (D) Phosphofructokinase
Description : An allosteric enzyme is generally inhibited by (A) Initial substrate of the pathway (B) Substrate analogues (C) Product of the reaction catalysed by allosteric enzyme (D) Product of the pathway
Description : An example of enzyme inhibition: (A) Reversible inhibition (B) Irreversible inhibition (C) Allosteric inhibition (D) All of these ENZYMES 151
Description : In gluconeogensis, an allosteric activator required in the synthesis of oxaloacetate from bicarbonate and pyruvate, which is catalysed by the enzyme pyruvate carboxylase is (A) Acetyl CoA (B) Succinate (C) Isocitrate (D) Citrate
Description : The rate of citric acid cycle is controlled by the allosteric enzyme: (A) Aconitase (B) Fumarase (C) Fumarase (D) Malate dehydrogenase
Description : A demonstrable inducer is absent in (A) Allosteric enzyme (B) Constitutive enzyme (C) Inhibited enzyme (D) Co-operative enzyme ENZYMES 141
Description : An inducer is absent in the type of enzyme: (A) Allosteric enzyme (B) Constitutive enzyme (C) Co-operative enzyme (D) Isoenzymic enzyme
Description : An allosteric enzyme responsible for controlling the rate of T.C.A cycle is (A) Malate dehydrogenase (B) Isocitrate dehydrogenase (C) Fumarase (D) Aconitase
Last Answer : B
Description : Which of the following compound is a positive allosteric modifier of the enzyme pyruvate carboxylase? (A) Biotin (B) Acetyl CoA (C) Oxaloacetate (D) ATP
Last Answer : A
Description : PH is the negative logarithm of the hydrogen Ion Concentration express4ed in moles/liter of aqueous solution. PH of buffer solution is calculated by. Henderson's equation Name the best ... Chemical kinetics deals with study of. Rates and mechanisms of chemical and Biochemical reactions
Last Answer : What does Thermodynamics helps in predicting ?
Description : The phenomenon of inhibition of glycolysis by O2 is termed as (A) Red drop (B) Pasteur effect (C) Michaelis effect (D) Fischer’s effect
Description : A substance unrelated to substrate but capable of reversibly changing activity of enzyme by binding to a site other than active site is called (a) Competitive inhibitor (b) Non-competitive inhibitor (c) Catalytic inhibitor (d) Allosteric modulator/inhibitor
Last Answer : Ans. ((d))
Description : Allosteric enzymes are A- larger than simple enzyme B- smaller than simple enzyme C- larger and more complex than simple enzyme D- .smaller than simple enzyme but not complex
Last Answer : larger and more complex than simple enzyme
Description : The organophosphates produce irreversible inhibition of cholinesterase because: A. They bind to an allosteric site of the enzyme resulting in unfavourable conformation of esteratic site to bind ... degradation of enzyme molecules D. They are neither metabolized nor excreted from the body
Last Answer : B. Regeneration time of the phosphorylated enzyme is longer than the turnover time of the enzyme molecules
Description : The applicability of Noyes-Whitney equation is to describe (A) First order kinetics (B) Zero order kinetics (C) Mixed order kinetics (D)Dissolution rate
Last Answer : (D)Dissolution rate
Description : If you were to plot the height of everyone in your class on graph the values would probable form a hill-shaped curve called?
Last Answer : logistic model
Description : Does Sebastian Michaelis have a brother?
Last Answer : no
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 : AMP is an allosteric inhibitor of (A) PRPP synthetase (B) Adenylosucciante synthetase (C) Both (A) and (B) (D) None of these
Description : GMP is an allosteric inhibitor of all the following except (A) PRPP synthetase (B) PRPP glutamyl amido synthetase (C) IMP dehydrogenase (D) Adenylosuccinate synthetase
Description : An allosteric inhibitor of IMP dehydrogenase is (A) AMP (B) ADP (C) GMP (D) GDP
Description : An allosteric inhibitor of adenylosuccinate synthetase is (A) AMP (B) ADP (C) GMP (D) GDP