Description : Pick out the wrong statement. (A) Wine, rum & Vodka are prepared by the formulation of fruit juice, sugar beet & rye respectively (B) Protein catalysts are called enzymes (C) The rate ... concentration of reactants at high concentration of enzymes (D) Total sugar content in molasses is about 10%
Last Answer : (D) Total sugar content in molasses is about 10%
Description : Enzymes are different from catalysts in (A) Being proteinaceous (B) Not used up in reaction (C) Functional at high temperature (D) Having high rate of diffusion
Last Answer : Answer : A
Description : (4) None of these Explanation: Catalysis is the change in rate of a chemical reaction due to the participation of a substance called a catalyst. Unlike other reagents that ... may participate in multiple chemical transformations. Catalysts that speed the reaction are called positive catalysts.
Last Answer : Table salt gets moist during rainy season because – (1) sodium chloride is hygroscopic (2) sodium chloride is deliquescent (3) sodium chloride contains some quantity of sodium iodide (4) sodium chloride contains hygroscopic impurities like magnesium chloride
Description : Three of the following statements about enzymes are correct and one is wrong. Which one is wrong? (a) Enzymes require optimum pH for maximal activity. (b) Enzymes are denatured at high temperature but ... - 90°C. (c) Enzymes are highly specific. (d) Most enzymes are proteins but some are lipids.
Last Answer : (d) Most enzymes are proteins but some are lipids.
Description : Which of the following statements about enzymes is wrong? (a) Enzymes are denatured at high temperatures. (b) Enzymes are mostly proteins but some are lipids also. (c) Enzymes are highly specific. (d) Enzymes require optimum pH and temperature for maximum activity
Last Answer : (b) Enzymes are mostly proteins but some are lipids also.
Description : Enzymes are organic catalysts used in the __________ reactions. (A) Chemical (B) Biochemical (C) Photochemical (D) Electrochemical
Last Answer : (B) Biochemical
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 : Proteinous substances which catalyze biochemical reactions are known as (A) Activators (B) Catalysts (C) Enzymes (D) Hormones
Last Answer : Answer : C
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 : Organic catalysts differ from the inorganic catalyst in the sense that the former is (A) Active at cryogenic temperatures only (B) Prohibitively costly (C) Proteinous in nature (D) Active at very high temperature only
Last Answer : (C) Proteinous in nature
Description : Which of the following is not true regarding enzymes? (A) They catalyze only a particular type of reaction (B) They remain active even after separation from the source (C) They are destroyed ... They are irreversibly destroyed at high temperature (E) Their activity depends on the pH of the solution
Description : Enzymes are sensitive to (a) Heat (b) pH (c) Poisons (d) All three
Last Answer : Ans:(d)
Description : Pick out the wrong statement. (A) Use of different catalysts in a reversible catalytic chemical reaction does not change the equilibrium composition (B) Alumina is added as a promoter to ... Arrhenius plot (D) Presence of inerts affects the equilibrium conversion of reactants in a chemical reaction
Last Answer : (C) Activation energy for a reaction is obtained from the intercept of the Arrhenius plot
Description : Enzymes and catalysts similarities -Biology
Last Answer : answer:
Description : Fermentation is a process of decomposition of an organic compound by (1) catalysts (2) enzymes (3) carbanions (4) free radicals
Last Answer : (2) enzymes Explanation: Fermentation in food processing typically is the conversion of carbohydrates to alcohols and carbon dioxide or organic acids using yeasts, bacteria, or a combination there ... to lactic acid. Alcoholic fermentation follows the same enzymatic pathway for the first 10 steps.
Description : Fermentation is a process of decomposition of an organic compound by : (1) catalysts (2) enzymes (3) carbanions (4) free radicals
Last Answer : enzymes
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 : Substances that cause a reaction to occur or proceed at a different rate without the reaction itself being affected are called - (1) Catalysts (2) Hydrocarbons (3) Oxidising agents (4) Substitutes
Last Answer : (1) Catalysts Explanation: Catalysts are substances that cause a reaction to occur or proceed at a different rate without the reaction itself being affected. Eg: hydrogenation of vegetable oils using a nickel catalyst.
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 : The Rate Law expresses the rate of a reaction in terms of the concentrations of the: w) reactants x) products y) by-products z) catalysts
Last Answer : ANSWER: W -- REACTANTS
Description : Enzymes are a. Inorganic compounds. b. Destroyed in a reaction. b. Proteins. a. Vitamins.
Last Answer : c
Description : Arrhenius equation K = Ae-E a / R T In some reactions, Rate of reaction is directly proportional to. Concentration of catalyst Catalyst used in Bio-Chemical reactions is called. Enzymes Reactions catalyzed by light are called as. Photo catalyzed or Photosensitised reactions
Last Answer : Define order of reaction
Description : Coenzyme is (A) Often a vitamin (B) Always an inorganic compound (C) Always a protein (D) Often a metal ENZYMES 173
Description : Which of the following enzymes incorporates inorganic phosphate into the substrate? (A) Phosphoglycerate kinase (B) Glyceraldehyde-3-phosphate dehydrogenase (C) Pyruvate kinase (D) Enolase
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
Last Answer : Answer : D
Description : Dry seeds endure higher temperature than germinating seeds as (A) Hydration is essential for making enzymes sensitive to temperature (B) Dry seeds have a hard covering (C) Dry seeds have more reserve food (D) Seedlings are tender
Description : What organic molecule function as a catalysts for chemical reactions in living organisms?
Last Answer : They are called enzymes, but there a probably billions of different enzymes. They are built from protein molecules decorated with sugars and sometimes include one or more metal atoms at their "active" site.
Description : . Photo-chemical reactions occur in presence of (A) Sunlight (B) Darkness (C) Solid catalysts (D) Monochromatic radiation only
Last Answer : (A) Sunlight
Description : Which of the following statements is correct? (a) Sporopollenin can be degraded by enzymes. (b) Sporopollenin is made up of inorganic materials. (c) Sporopollenin can withstand high temperatures ... strong acids and alkalis. (d) Sporopollenin can withstand high temperatures but not strong acids.
Last Answer : (c) Sporopollenin can withstand high temperatures as well as strong acids and alkalis
Description : Pick out the wrong statement. (A) Alkylation produces a larger iso-paraffin (having higher octane number) from the reaction of an olefin with smaller iso-paraffin (B) Catalytic alkylation processes use HF ... (> 1000°C) (D) Gasoline having an octane number of 90 can be produced by alkylation process
Last Answer : (C) All the alkylation processes use very high temperature (> 1000°C)
Description : Template/lock and key theory of enzyme action is supported by (A) Enzymes speed up reaction (B) Enzymes occur in living beings and speed up certain reactions (C) Enzymes determine the direction of reaction (D) Compounds similar to substrate inhibit enzyme activity
Description : At very high concentration of enzymes, the rate of fermentation chemical reaction is __________ the concentration of reactants. (A) Independent of (B) Directly proportional to (C) Inversely proportional to (D) Proportional to the square of
Last Answer : (A) Independent of
Description : Enzymes are – (1) Micro organisms (2) Proteins (3) Inorganic compounds (4) Moulds
Last Answer : (2) Proteins Explanation: Enzymes are proteins that act as a catalyst, lowering the activation energy of a reaction, therefore dramatically increasing the rate of the reaction. Like all ... of amino acids that fold to produce a three-dimensional product which determines their specific activities.
Description : Enzymes are A- organic compounds produced by living organism B- .inorganic compounds C- organic as well as inorganic compounds D- all of these
Last Answer : organic compounds produced by living organism
Description : Enzymes are : (1) Micro organisms (2) Proteins (3) Inorganic compounds (4) Moulds
Last Answer : Proteins
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 : The pH optima of most of the enzymes is (A) Between 2 and 4 (B) Between 5 and 9 (C) Between 8 and 12(D) Above 12
Last Answer : Answer : B
Description : What is the optimum pH of usual enzymes?
Last Answer : Usually enzymes have the optimum pH between 6 and 8.
Description : Cytosolic and mitochondrial carbamoyl phosphate synthetase have the following similarity: (A) Both use ammonia as a substance (B) Both provide carbamoyl phosphate for urea synthesis (C) Both require N-acetylglutamate as an activator (D) Both are allosteric enzymes
Description : The process in which organisms do not require light and pigment and synthesize their, food utilizing energy released by the oxidation of inorganic and
Last Answer : The process in which organisms do not require light and pigment and synthesize their, food ... B. Heterotrophism C. Chemosynthesis D. Saprophytism
Description : Which of the following statements is true? (A) Enzymes have names ending ase (B) Enzymes are highly specific in their action (C) Enzymes are living organisms (D) Enzymes get activated on heating
Description : All the following statements about hormones are true except (A) All of them require specific carriers in plasma (B) All of them require specific receptors in target cells (C) Some of them are subject to feedback regulation (D) Some of them increase the transcription of certain genes
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 : In most metabolic pathways, all needed enzymes are arranged together in a multienzyme complex within a (A) Solution of ATP (B) Membrane (C) Quanternary protein (D) Coenzyme
Description : What are the co-enzymes needed for fatty acid oxidation?
Last Answer : FAD and NAD.
Description : (2) Nitrogen, Phosphorous and Sodium Explanation: Fertilizer (or fertiliser) is any organic or inorganic material of natural or synthetic origin (other than liming materials) that is added to a ... essential to the growth of plants. The three elements most needed in common fertilisers are Nitrogen.
Last Answer : Metal are good conductors, because – (1) they contain free electrons (2) the molecules in them are very close to each other (3) the molecules in them collide very freely (4) they contain reflecting surface
Description : Low voltage releases as used in some shipboard motor starter and control equipment will have which of the following characteristics? A. They trip circuit contactors when the motor starts to overspeed. B. ... coil of the starter. D. They allow the motor to restart upon restoration of normal voltage.
Last Answer : Answer: D
Description : Which of the following is true in relation to dental decay? A. Foods that require vigorous mastication will increase salivary flow and reduce PH B. Tooth brushing immediately after meals is most ... E. The Stephan Curve describes an increase in PH during a meal with resultant of demineralisation
Last Answer : E. The Stephan Curve describes an increase in PH during a meal with resultant of demineralisation
Description : __________ is the controlling step in a highly temperature sensitive fluid-solid non-catalytic reaction. (A) Gas film diffusion (B) Ash diffusion (C) Chemical reaction (D) None of these
Last Answer : (C) Chemical reaction