Description : Role of an enzyme in reactions is to/as (a) decrease activation energy (b) increase activation energy (c) inorganic catalyst (d) none of the above.
Last Answer : (a) decrease activation energy
Description : Main function of an enzyme is to A- increase the activation energy B- decrease the activation energy C- maintain constant activation energy D- .none of these
Last Answer : decrease the activation energy
Description : Which one of the following statements regarding a catalyst is not correct? A An enzyme is a catalyst that only binds certain substrates. B An enzyme is a protein that is a highly ... increasing the activation energy. D Catalysts do not alter the equilibrium constant for a chemical reaction.
Last Answer : C Catalysts increase the rate of a reaction by altering the mechanism, thereby increasing the activation energy.
Description : An enzyme promotes a chemical reaction by (A) Lowering the energy of activation (B) Causing the release of heat which acts as a primer (C) Increasing molecular motion (D) Changing the free energy difference between substrate and product
Last Answer : Answer : A
Description : The increase in the rate of reaction with temperature is due to (A) Increase in the number of effective collisions (B) Decrease in activation energy (C) Increase in the average kinetic energy of the reacting molecules (D) None of these
Last Answer : (B) Decrease in activation energy
Description : An increase in which of the following results in a decrease in the rate of the chemical reaction? (a) temperature (b) concentration (c) collision frequency (d) energy of activation
Last Answer : energy of activation
Description : Which of the following is incorrect about heterogeneous catalysis? a. The most effective catalysts are those which have small surface area b. Seperation of catlyst is easy c. Increase in the rate of reaction is due to decrease in the activation energy d. It is based upon the phenomenon of adsorption
Last Answer : a. The most effective catalysts are those which have small surface area
Description : Enzymes increase the rates of reactions by (A) Increasing the free energy of activation (B) Decreasing the energy of activation (C) Changing the equilibrium constant of the reaction (D) Increasing the free energy change of the reaction
Last Answer : Answer : B
Description : Methylxanthine drugs such as aminophylline cause which one of the following? (a) Vasoconstriction in many vascular beds (b) Decrease in the amount of cAMP in mast cells (c) Bronchodilation (d) Activation of the enzyme phosphodiesterase (e) Sedation
Last Answer : Ans: C
Description : The figure given Progress of Reaction Product Substrate B A C D below shows the conversion of a substrate into product by an enzyme. In which one of the four options (A-D ... enzyme enzyme (d) Activation Transition Activation Potential energy state energy energy with without enzyme enzyme
Last Answer : (b) Transition Potential Activation Activation state energy energy energy without with enzyme enzyme
Description : Enzymes (a protein) are catalysts found in organisms. Its efficiency of catalysing a reaction is due to its capacity to lower the activation energy of the reaction. The enzyme ptyalin used for food digestion is present in (A) Blood (B) Saliva (C) Intestine (D) Gland
Last Answer : (B) Saliva
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 : An enzyme which brings about lysis of bacterial cell wall is (A) Amylase (B) Lysozyme (C) Trypsin (D) Lipase
Description : Calcium is required for the activation of the enzyme: (A) Isocitrate dehydrogenase (B) Fumarase (C) Succinate thiokinase (D) ATPase
Last Answer : Answer : D
Description : For the activation of long chain fatty acids the enzyme thiokinase requires the cofactor: (A) Mg++ (B) Ca++ (C) Mn++ (D) K+
Description : What is the enzyme for this activation?
Last Answer : Thiokinase or fatty acyl CoA synthetase.
Description : Characteristics of Vitamin D and its metabolites include which one of the following? (a) Act to decrease serum levels of calcium (b) Activation of their Vitamin D receptors increases cellular CAMP ... Vitamin D increase renal excretion of calcium (e) Vitamin D deficiency results in Pager's disease
Description : The energy required to start an enzymatic reaction is called (A) Chemical energy (B) Metabolic energy (C) Activation energy (D) Potential energy
Last Answer : Answer : C
Description : Enzymes increases the rate of reactions by (A) Increasing the free energy of activation (B) Decreasing the energy of activation (C) Changing the equilibrium constant of the reaction (D) Increasing the free energy change of the reaction
Description : Enzymes accelerate the rate of reactions by (A) Increasing the equilibrium constant of reactions (B) Increasing the energy of activation (C) Decreasing the energy of activation (D) Decreasing the free energy change of the reaction
Description : The difference between Threshold energy and average energy of the molecules is called activation energy. Ina chemical reaction lowers the rate of reaction the greater will be. The activation energy
Last Answer : How do you define the molecularity of a reaction ?
Description : Production rate __________ with increased fineness, with a given energy input to the size reduction machine. (A) Decreases (B) Increases (C) Remains unchanged (D) May increase or decrease; depends on the machine
Last Answer : (A) Decreases
Description : Metabolism is carried out by a large class of proteins that decrease the activation energy required for chemical reactions inside a cell. Therefore they only facilitate reactions that would naturally occur at a much slower rate. What is the name of these proteins that speed up biochemical reactions?
Last Answer : Enzymes
Description : For a given Reynolds number, in a hydraulically smooth pipe, further smoothening __________ the friction factor. (A) Brings about no further reduction of (B) Increases (C) Decreases (D) None of these
Last Answer : (A) Brings about no further reduction of
Description : An enzyme which brings about the conversion of starch into maltose is known as
Last Answer : An enzyme which brings about the conversion of starch into maltose is known as A. Diastase B. Zymase C. Maltase D. Invertase
Description : Fight-or-flight reactions cause activation of (a) the parathyroid glands, leading to increased metabolic rate (b) the kidney, leading to suppression of renin- angiotensin-aldosterone pathway (c) ... epinephrine and norepinephrine (d) the pancreas leading to a reduction in the blood sugar levels.
Last Answer : (c) the adrenal medulla, leading to increased secretion of epinephrine and norepinephrine
Description : Isoenzymes can be characterized by (A) Proteins lacking enzymatic activity that are necessary for the activation of enzymes (B) Proteolytic enzymes activated by hydrolysis (C) Enzymes with identical primary structure (D) Similar enzymes that catalyse different reaction
Description : A bob of simple pendulum oscillating in air is made to oscillate in oil. The time period will a.Increase b.Decrease c.Not change d.Decrease but reduction depends on viscosity of oil e.None of the above
Last Answer : a. Increase
Description : For reduction enzyme HMG-CoA reductase requires cofactor: (A) NADPH (B) NADP (C) NAD (D) FAD
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 : How will a reduction in 'Bank Rate' affect the availability of credit? (1) Credit will increase (2) Credit will not increase (3) Credit will decrease (4) None of these
Last Answer : (1) Credit will increase Explanation: Bank rate, also referred to as the discount rate, is the rate of interest which a central bank charges on the loans and advances to a commercial bank. ... bank becomes more expensive. It is more applicable when there is a liquidity crunch in the market.
Description : Which one of the following does project change control primarily seek to ensure? a. All variance to the project scope is evaluated. b. No reduction in the perceived quality of the project outcome. ... project do not increase. d. Any decrease in the scoped deliverable of the project is rejected.
Last Answer : a. All variance to the project scope is evaluated.
Description : Which one of the following does project change control primarily seek to ensure? a. All variance to the project scope is evaluated. b. No reduction in the perceived quality of the project outcome ... project do not increase. d. Any decrease in the scoped deliverable of the project is rejected
Description : Weathering of coal during storage causes (A) Reduction in coal size (B) Increase in its friability (C) Decrease in its caking capacity (D) All (A), (B) and (C)
Last Answer : (D) All (A), (B) and (C)
Description : Addition of pozzolana to ordinary port land cement, causes (A) Decrease in early strength (B) Reduction in chemical action with sulphates (C) Increase in shrinkage (D) All the above
Last Answer : Answer: Option D
Description : Demand pull inflation may be caused by (a) An increase in cost (b) A decrease in interest rate © A reduction in government spending (d) An outward shift of aggregate supply.
Last Answer : (b) A decrease in interest rate
Description : Morphine induced constipation involves the following mechanisms except: A. Increase in tone and decrease in propulsive activity of intestinal muscles B. Antivagal action C. Spasm of gastrointestinal sphincters D. Reduction of gastrointestinal secretions
Last Answer : B. Antivagal action
Description : How will a reduction in ‘Bank Rate’ affect the availability of credit ? (1) Credit will increase (2) Credit will not increase (3) Credit will decrease (4) None of these
Last Answer : Credit will increase
Description : Name the nondigestive enzyme which helps in activation of trypsinogen
Last Answer : Name the nondigestive enzyme which helps in activation of trypsinogen
Description : Fibrinolytic therapy is based on activation of plasminogen, the inactive proteolytic enzyme of plasma that binds to fibrin during the formation of thrombosis. Activation of plasminogen to plasmin results ... TPA all exceed 30 minutes d. Streptokinase is significantly cheaper than urokinase or TPA
Last Answer : Answer: a, b, d Streptokinase is a bacterial protein produced by group C b-hemolytic streptococci. It is therefore antigenic in humans and can be associated with allergic reaction in ... one agent over the other. Streptokinase however, is markedly less expensive than either urokinase or TPA
Description : The best understood intracellular messenger is cyclic AMP (cAMP). Which of the following statement(s) concerning this intracellular messenger is/are correct? a. Intracellular cyclic AMP is constantly ... of adenylate cyclase d. cAMP is the only cyclic nucleotide active as an intracellular messenger
Last Answer : Answer: a, b The prototypic intracellular messenger is cAMP. To function as a mediator, the concentration of cAMP must change rapidly. In resting cells, cAMP is continuously being degraded by ... produce cGMP. Intracellular calcium ions also serve as second messengers in a large number of cells
Description : Besides being fundamental for the activation of the main gastric digestive enzyme how does HCl also directly participate in digestion?
Last Answer : With its corrosive effect, HCl also helps the rupture of the adhesion between food particles, facilitating the digestive process.
Description : Which one of the following is not a function of the liver? (1) Regulation of blood sugar (2) Enzyme activation (3) Detoxiation (4) Reproduction
Last Answer : (4) Reproduction Explanation: Liver is the body's largest internal organ. It has many functions in the body like it helps in protein synthesis and blood clotting, manufacturing triglycerides and cholesterol, glycogen synthesis, and bile production.
Last Answer : (4) Reproduction Explanation: Liver is the body’s largest internal organ. It has many functions in the body like it helps in protein synthesis and blood clotting, manufacturing triglycerides and cholesterol, glycogen synthesis, and bile production.
Description : Boron in green plants assists in (a) activation of enzymes (b) acting as enzyme co-factor (c) photosynthesis (d) sugar transport.
Last Answer : (d) sugar transport.
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 : The complement system consists of a series of serum proteins that exist in a quiescent or very low-level state of activation in the uninfected host. Which of the following ... certain complement components serve as chemoattractants to additional cellular components of the host defense mechanism
Last Answer : Answer: a, c, d Complement activation can occur through either classic or alternate (properdin) pathways, both of which eventuate in deposition of terminal complement pathway components on the ... and release of lysosomal enzymes that can directly damage certain target tissues, such as the lung
Description : Pick out the wrong statement: (A) Chemical reactions with high activation energy are very temperature sensitive (B) A flat velocity profile exists in a plug flow reactor (C) The residence ... D) Half life of a reaction increases with increased initial concentration for reaction orders more than one
Last Answer : (C) The residence time for all the elements of fluid in case of a P.F.R. need not be same
Description : Unidirectional tandem gene arrays are significant in ________ a. Increase in recombinant gene product with increasing plasmid number. b. Increase in recombinant gene product without increasing plasmid ... increasing plasmid numbers. d. Decrease in strong promotor with increase in plasmid number
Last Answer : b. Increase in recombinant gene product without increasing plasmid number.