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
Last Answer : Answer : C
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 : In enzyme assays, all the following are kept constant except (A) Substrate concentration (B) Enzyme concentration (C) pH (D) Temperature
Last Answer : Answer : B
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
Last Answer : Answer : A
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 : With reference to factors affecting the rate of photosynthesis, which of the following statements is not correct? (a) Increasing atmospheric CO2 concentration up to 0.05% can enhance CO2 fixation rate. ( ... for higher yield. (d) Light saturation for CO2 fixation occurs at 10% of full sunlight.
Last Answer : (b) C3 plants respond to higher temperature with enhanced photosynthesis while C4 plants have much lower temperature optimum
Description : With reference to factors affecting the rate of photosynthesis, which of the following statements is not correct ? (1) Increasing atmospheric CO 2 concentration up to 0.05% can enhance CO 2 fixation ... for higher yield (4) Light saturation for CO 2 fixation occurs at 10% of full sunlight
Last Answer : (2) C 3 plants respond to higher temperatures with enhanced photosynthesis while C 4 plants have much lower temperature optimum
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 : 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
Description : Maximum enzyme activity is observed at (A) Acidic pH (B) Neutral pH (C) Basic pH (D) Optimum pH
Description : The pH at which an enzyme has maximum activity is known as (A) Isoelectric pH (B) Optimum pH (C) Low pH (D) High pH
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 : 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 : 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 : 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
Description : Gastric enzyme pepsin acts only in acidic medium with in a limited pH concentration. It varies `:`
Last Answer : Gastric enzyme pepsin acts only in acidic medium with in a limited pH concentration. It varies `:` A. 1.20 to 1.80 ... C. 2.00 to 2.50 D. 1.50 to 2.60
Description : Vmax of an enzyme may be affected by (A) pH (B) Temperature (C) Non-competitive inhibitors (D) All of these
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
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 : 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 : Activity of an enzyme can be modulated by change of (1) pH (2) Light (3) Humidity (4) Rainfall
Last Answer : pH
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 effect of substrate concentration on enzyme activity? -Biology
Description : Concentration of substrate on enzyme activity. -Biology
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 : What are the factors affecting the mobility in electrophoresis?
Last Answer : Net charge on the particles (pI of proteins), mass and shape of the particles, the pH of the medium, strength of electrical field, and properties of the supporting medium.
Description : Factors affecting cooling of water in a cooling tower are: a. Temperature of air b. Humidity of air c. Temperature of hot air d. All of the above
Last Answer : Ans:- d. All of the above
Description : Prosthetic groups differ from co-enzymes in that (a) they require metal ions for their activity (b) they (prosthetic groups) are tightly bound to apoenzymes (c) their association with apoenzymes is transient (d) they can serve as co-factors in a number of enzyme-catalyzed reactions.
Last Answer : (b) they (prosthetic groups) are tightly bound to apoenzymes
Description : The greatest factor affecting herbicide adsorption is a). pH b). Salt c). SOM d). Soil nutrient
Last Answer : c). SOM
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 optimal pH for the enzyme chymotrypsin is (A) 2.0 (B) 4.0 (C) 6.0 (D) 8.0
Description : The optimal pH for the enzyme trypsin is (A) 1.0–2.0 (B) 2.0–4.0 (C) 5.2–6.2 (D) 5.8–6.2
Description : The optimal pH for the enzyme rennin is (A) 2.0 (B) 4.0 (C) 8.0 (D) 6.0
Description : The optimal pH for the enzyme pepsin is (A) 1.0–2.0 (B) 4.0–5.0 (C) 5.2–6.0 (D) 5.8–6.2
Description : In a solution having a pH of 7.4, the hydrogen ion concentration is (A) 7.4 nmol/L (B) 40 nmol/L (C) 56 nmol/L (D) 80 nmol/L
Description : Which of the following concerning the pH of urine is correct? 1) is a useful indicator of the acid/base balance of the blood 2) rises on a vegetarian diet 3) is determined by the concentration of ... lower than 5.5 in renal tubular acidosis 5) would be above 7.0 after prolonged and severe vomiting
Last Answer : Answers-2 c - excretion of ammonium occurs when an acid urine is produced but the pH of urine is of course determined by the concentration of H+ ions d-unable to lower the pH to ... and distal nephron and this perpetuates the metabolic alkalosis until the fluid balance is restored with IV fluids.
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 : Explain the process of digestion if a student puts a plain cracker in their mouth, chews it, and holds the mush in their mouth. Mention the pH, temperature, enzyme, substrate and products. ?
Last Answer : Part of the human body
Description : Trimethoprim inhibits bacteria without affecting mammalian cells because: A. It does not penetrate mammalian cells B. It has high affinity for bacterial but low affinity for mammalian dihydrofolate ... bacterial folate synthetase as well as dihydrofolate reductase enzymes D. All of the above
Last Answer : B. It has high affinity for bacterial but low affinity for mammalian dihydrofolate reductase enzyme
Description : Osteoporosis, an age-related disease of skeletal system, may occur due to (a) immune disorder affecting neuromuscular junction leading to fatigue (b) high concentration of Ca++ and Na+ (c) decreased level of estrogen (d) accumulation of uric acid leading to inflammation of joints.
Last Answer : (c) decreased level of estrogen
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 : 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 : Km value of enzyme is substrate concentration at (A) ½ Vmax (B) 2 Vmax (C) ½ Vmax (D) 4 Vmax
Description : Feedback term refers to (A) Effect of substrate on rate of enzymatic reaction (B) Effect of end product on rate reaction (C) Effect of enzyme concentration on rate of reaction (D) Effect of external compound on rate of reaction
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 : 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
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 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 : 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