3. Enzymes Flashcards
What is an enzyme?
a protein biological catalyst, that speeds up chemical reactions by lowering the activation energy of reactions.
Draw a 3-part enzyme diagram.
Explain what determines the structure of the active site.
Because the enzyme (protein) is made from a sequence of amino acids then the R groups from these determine the bonds that will form. Therefore leading to the overall 3D structure, including the active site.
Define metabolism
The sum total of all chemical reactions occurring in an organism
What does a synthesis reaction mean?
Two substrates combine to form one product
What does a decomposition reaction mean?
One substrate breaks down to form two products
What factors affect the rate of enzyme reactions?
Temperature
pH
Enzyme concentration
Substrate concentration
Competitive inhibitors
Non-competitive inhibitors
Draw an enzyme Rate of reaction vs temperature graph
Explain why the enzyme controlled reaction is low at a low temperature
Because the enzymes are inactive
Then there is less kinetic energy and it is less likely to have successful collisions between enzymes and substrate
Therefore less enzyme-substrate complexes will form, less products will form and there is a lower rate of reaction
Define optimum temperature
Temperature where the enzyme works best and there is the most enzyme substrate complexes forming.
Explain why the enzyme controlled reaction is low at a high temperature
Because there is too much kinetic energy the enzyme’s denature
Then the 3D structure of the active site has changed shape so it is no longer specific and complementary to the substrate
Therefore less enzyme-substrate complexes will form and there will be less products and a lower rate of reaction.
Draw an enzyme Rate of reaction reaction vs pH graph
Explain why the enzyme controlled reaction is low at a low pH
Because the pH is too low the enzyme’s denature
Then the 3D structure of the active site has changed shape so it is no longer specific and complementary to the substrate.
Therefore less enzyme-substrate complexes will form and there will be less products formed and a lower rate of reaction.
Explain why the enzyme controlled reaction is low at a high pH
Because the pH is too high the enzyme’s denature
Then the 3D structure of the active site has changed shape so it is no longer specific and complementary to the substrate.
Therefore less enzyme-substrate complexes will form and there is less products and a lower rate of reaction.
Draw an enzyme rate of reaction vs enzyme concentration (assuming unlimited substrate concentration)
Draw an enzyme rate of reaction vs substrate concentration graph
Draw a 3-part enzyme diagram showing competitive inhibition
Remember to always draw the normal 3-part enzyme diagram first.
Draw a 3-part enzyme diagram showing non-competitive inhibition
