CIE A Level Biology復習筆記3.2.2 Rate: pH
Rate: pH All enzymes have an?optimum pH?or a pH at which they operate best Enzymes are?denatured?at extremes of pH Hydrogen?and ionic bonds?hold the tertiary structure of the protein (ie. the enzym...
CIE A Level Biology復習筆記3.2.1 Rate: Temperature
Rate: Temperature Enzymes have a?specific optimum temperature?– the temperature at which they catalyse a reaction at the?maximum rate Lower temperatures?either?prevent?reactions from proceeding or?...
CIE A Level Biology復習筆記3.1.5 Colorimetry
Colorimetry to Measure Enzyme Activity A?colorimeter?is able to measure?light absorbance?(how much light is absorbed) or?light transmission?(how much light passes through) a substance Colorimetry c...
CIE A Level Biology復習筆記3.1.4 Measuring Enzyme Activity
Measuring Enzyme Activity The?progress?of?enzyme-catalysed reactions?can be investigated by: Measuring the?rate of formation of a product?using catalase Measuring the?rate of disappearance of a sub...
CIE A Level Biology復習筆記3.1.3 How Enzymes Work
How Enzymes Work The lock-and-key hypothesis Enzymes are?globular proteins This means their?shape?(as well as the shape of the?active site?of an enzyme) is determined by the complex tertiary struct...
CIE A Level Biology復習筆記3.1.2 Enzyme Action
Mode of Enzyme Action Enzymes have an?active site?where?specific substrates bind?forming an?enzyme-substrate complex The?active site?of an enzyme has a?specific shape?to fit a specific substrate Ex...
CIE A Level Biology復習筆記3.1.1 Enzymes
Enzymes as Proteins Enzymes are?biological catalysts ‘Biological’ because they function in?living systems ‘Catalysts’ because they?speed up the rate of chemical reactions?without being used up or c...
CIE A Level Biology復習筆記2.4.2 The Role of Water in Living Organisms
Water Molecules: In Living Organisms Water has many essential roles in living organisms due to its properties: The?polarity?of water molecules The presence and number of?hydrogen bonds?between wate...
CIE A Level Biology復習筆記2.4.1 Water & the Hydrogen Bond
Water Molecules: Hydrogen Bonds Water is of great biological importance. It is the medium in which all metabolic reactions take place in cells. Between 70% to 95% of the mass of a cell is water As ...
