Enzymes

Question 1

How does an enzyme reduce activation energy?

Answer 1

Substrate fits into enzyme forming enzyme-substrate complex

If two substrate molecules are being joined enzyme holds them closer together reducing any repulsion so bond more easily

Can catalyse break down as a substrate fitting into the active site puts strain on bonds so they break up more easily

Question 2

By lowering the amount of activation energy in a reaction what does this mean

Answer 2

Reactions can happen at a lower temperature

So speeds up rate of reaction

Question 3

Describe the lock and key model

Answer 3

When the substrate fits into the enzyme in the same way a key fits into a lock

Good start but know that the enzyme substrate complex changes shape slightly to complete the fit

Enzyme unchanged after the reaction

Question 4

Explain the induced fit model

Answer 4

Helps to explain why enzymes are so specific

Substrate has to be right shape but make the active site change shape in the right way as well

When enzyme substrate complex is formed the substrate binds to the active sight so changes slightly

Question 5

How do enzyme properties relate to their tertiary structure?

Answer 5

V specific because only one complementary substrate will fit in the active site

Active sites shape is determined by the tertiary structure so a different shaped active site

If tertiary structure is alternated in any way enzyme substrate complexes will not form

Could be altered by ph or temp

Primary structure is determined by a gene if mutation in gene occurs could effect tertiary structure of enzyme produced

Question 6

Give a general overview of what an enzyme is

Answer 6

Biological catalyst
Catalyses metabolic reactions
Can be intercellular or extra cellular
They r protiens
Active site with specific shape so substrate molecules can bind to
Highly specific due to tertiary structure