Which of statements about enzymecatalyzed reactions is TRUE
     Which of statements about enzyme-catalyzed reactions is TRUE?  The rate of the reaction is independent of rate of all temperature.  The real of all enzyme-catalyzed reactions is decreased when the pH is lowered from 7 to 2.  The rate of the reaction is independent of substrate concentration  Under given conditions of substrate concentration, pH and temperature the rate of product formation varies directly with enzyme concentration up to a maximum, at which point the rate cannot be increased further.  Which of the following statements about lactate dehydrogenises is TRUE?  It is a protein.  It oxidizes lactic acid  It reduces another molecule (acid).  All of the above are correct.  In a metabolic pathway, the product of one enzyme reaction becomes the substrate of the next enzyme reaction.  the substrate of one enzyme reaction becomes the product of the next enzyme reaction.  The conversion of glucose to 2 molecules of  acid is called  oxidative phosphorylation  glycogen sis  glycogenolysis  glycolysis  The net gain of ATP per glucose molecule in lactic acid fermentation is  the net gain in aerobic respiration is generally  2, 4  2, 30  30, 2  24, 38  In anaerobic respiration, the oxidizing agent for NADH (that is, the molecules that remove electrons from NADH) is  pyruvic acid.  lactic acid.  citric acid.  ATP.  The conversion of lactic acid to  acid occurs  in anaerobic respiration.  in the heart, where lactic acid is aerobically respired  in the liver, where lactic acid is converted to glucose.  Both A and Bare true  Bothe Band Care true. 
  
  Solution
12. (D)
By increasing the enzyme concentration, the maximum reaction rate greatly increases
13, (D)
Lactate dehydrogenase is an enzyme which catalyses reversible conversion of pyruvate to lactate.
14. (a)
Product of a reaction serves as the substrate for next enzyme reaction.
15.(d)
Glycolysis breaks down glucose to two 3 carbon compounds pyruvate

