Description : Maximum enzyme activity is observed at (A) Acidic pH (B) Neutral pH (C) Basic pH (D) Optimum pH
Last Answer : Answer : D
Description : Velocity maximum for an enzyme at half the substrate concentration gives (A) The molecular weight of the enzyme (B) Km value (C) Isoelectric pH (D) Pk value
Last Answer : Answer : B
Description : In the genetic disorder of cystinuria, the patient excretes large quantities of cystine in their urine and its low solubility causes crystalline cystine to precipitate as stones in kidneys. The remedy ... C) NaHCO3 prevents stone formation by hydrolysis of cystine to cysteine (D) None of these
Last Answer : Answer : C
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 : Isoelectric pH is that pH at which protein is electrically: (A) Neutral (B) Anionic (C) Cationic (D) None of these
Last Answer : Answer : A
Description : This technique takes the advantage of the fact that each protein has different pH at which it is electrically neutral i.e., its isoelectric pH: (A) Isoelectric focussing (B) Immunoel Ectro Phoresis (C) Chromatography (D) HPLC
Description : Isoelectric pH of an amino acid is that pH at which it has a (A) Positive charge (B) Negative charge (C) Nil net charge (D) None of these
Description : Isoelectric pH of an amino acid is that pH at which it has a (A) Positive charge (B) Negative charge (C) No charge (D) None of these
Description : Isoelectric pH of an amino acid is that pH at which it has a (A) Positive charge (B) Negative charge (C) No net charge (D) All of these
Description : At a pH below the isoelectric point, an amino acid exists as (A) Cation (B) Anion (C) Zwitterion (D) Undissociated molecule
Description : At isoelectric pH, an amino acid exists as (A) Anion (B) Cation (C) Zwitterion (D) None of these
Description : Since the pK values for aspartic acid are 2.0, 3.9 and 10.0, it follows that the isoelectric (pH) is (A) 3.0 (B) 3.9 (C) 5.9 (D) 6.0
Description : pH (isoelectric pH) of alanine is (A) 6.02 (B) 6.6 (C) 6.8 (D) 7.2
Last Answer : (A) 3.0
Last Answer : (A) 6.02
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
Description : The pH at which the amino acid shows no tendency to migrate when placed in an electric field is known as its : (a) Isoelectric point (b) Dipole moment (c) Iodine number (d) Wavelength
Last Answer : Isoelectric point
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 : The catalytic efficiency of two different enzymes can be compared by the (a) formation of the product (b) pH of optimum value (c) Km value (d) molecular size of the enzyme.
Last Answer : (c) Km value
Description : The isoelectric point of a protein is (a) the pH at which the protein molecule has no charges on its surface. (b) the pH at which a protein in solution has an equal number of positive and negative charges. (c) the electric charge under isothermal conditions. (b) None of these
Last Answer : the pH at which a protein in solution has an equal number of positive and negative charges
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 : 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 : Factors affecting enzyme activity: (A) Concentration (B) pH (C) Temperature (D) All of these
Description : What is the effect of pH on the activity of an enzyme?
Last Answer : Each enzyme has an optimum pH, on both sides of which the velocity will be drastically reduced. The graph will show a bell-shaped curve.
Description : The optimum pH of pancreatic lipase is (A) 2.0 (B) 4.0 (C) 6.0 (D) 8.0
Description : The only correct statement about chymotrypsin is (A) It is formed from trypsin (B) Carboxypeptidase converts trypsin into chymotrypsin (C) Its optimum pH is around 7 (D) It hydrolyses peptide bonds involving basic amino acids
Description : All the following statements about pepsin are correct except (A) It is smaller than pepsinogen (B) It is formed by the action of HCl on its precursor (C) Its optimum pH is 1.0–2.0 (D) It hydrolyses the C-terminal and N-terminal peptide bonds of proteins
Description : What is the optimum pH of usual enzymes?
Last Answer : Usually enzymes have the optimum pH between 6 and 8.
Description : The solubility of most proteins is lowered at high salt concentrations is called as (A) Salting in process (B) Salting out process (C) Isoelectric focussing(D) None of these
Description : The rate of most enzyme catalysed reactions changes with pH. As the pH increases, this rate (A) reaches a minimum, then increases (B) reaches a maximum, then decreases (C) increases (D) decreases
Description : The temperature at which the catalytic activity of the catalyst is maximum, is called (1) room temperature (2) critical temperature (3) absolute temperature (4) optimum temperature
Last Answer : d) optimum temperature
Description : How does pH affect enzyme activity? -Biology
Last Answer : answer:
Description : Activity of an enzyme can be modulated by change of – (1) pH (2) Light (3) Humidity (4) Rainfall
Last Answer : (1) pH Explanation: Changes in pH which can accompany metabolic process such as respiration (aerobic glycolysis for example) can alter the conformation of an enzyme and hence enzyme activity. The ... ) which can lead to an alteration in the delicate balance of forces that affect protein structure
Description : The curve given below shows enzymatic activity in relation to three conditions (pH, temperature and substrate concentration). What do the two axes (X and Y) represent? X-axis ... (b) Temperature Enzyme activity (c) Substrate Enzymatic concentration activity (d) Enzymatic activity Temperature
Last Answer : (b) Temperature Enzyme activity
Description : Activity of an enzyme can be modulated by change of (1) pH (2) Light (3) Humidity (4) Rainfall
Last Answer : pH
Description : Isoelectric point of amino acids is used for (A) Crystallisation (B) Precipitation (C) Solubility (D) Reactivity
Description : Which of the following techniques is used to separate proteins based upon differences in their mass? (A) Isoelectric focusing (B) Dialysis (C) SDS-gel Electrophoresis (D) Western blotting
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 : Pick up the correct statement from the following: (A) A maximum value of dry density is obtained at optimum water content (B) At low value of water content most soils tend to be stiff (C) At high water content, the dry density decreases with an increase of water content (D) All the above
Last Answer : Answer: Option D
Description : The enzyme glycerol kinase is low activity in (A) Liver (B) Kidney (C) Intestine (D) Adipose tissue
Description : 20. Which one of the following statements is incorrect about enzyme catalysis? (1) Enzymes are least reactive at optimum temperature (2) Enzymes are mostly proteinous in nature (3) Enzyme action is specific (4) Enzymes are denaturated by ultraviolet rays and at high temperature
Last Answer : Enzymes are least reactive at optimum temperature
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 : What is the optimum PH for tryspin?
Last Answer : Need answer
Description : pH value of soil is maintained at __________ by the addition of fertiliser for optimum growth and health of the plant. (A) 4-5 (B) 7-8 (C) 9-10 (D) 12-13
Last Answer : (B) 7-8
Description : What is the optimum pH range for the cultivation of onion? a. 3.2-4.0 b. 5.8-6.5 c. 4.2-5.0 d. 8.9-10.6
Last Answer : b. 5.8-6.5
Description : Which is the optimum PH for nitrification? (Agriculture MCQ) a. 8.5 b. 9.5 c. 10 d. 7.5
Last Answer : a. 8.5
Description : For most bacteria, the optimum pH for growth lies between A- .6.5-7.5 B- B.3.5-4.5 C-.4.5-5.5 D-.5.5-6.5
Last Answer : 6.5-7.5
Description : An inorganic ion required for the activity of an enzyme is known as (A) Activator (B) Cofactor (C) Coenzyme (D) None of these