30.3 Enzymes

Question 1

What are enzymes

Answer 1

• Protein based catalysts found in living things. Usually globular proteins
• They speed up reactions
• They are extremely specific so each enzyme is optimised for ones reaction

Question 2

What is an active site

Answer 2

• All enzymes have them, like a crevice
• This allows for a reacting molecule to fit in perfectly so they are held in correct orientation to react
• Only molecules complimentary to active site can react

Question 3

What does it mean if an enzyme is stereospecific

Answer 3

Many enzymes only catalyse reactions for one enantiomer as their active sites are only specific to one

Question 4

How are enzymes denatured

Answer 4

• By changing internal conditions eg PH and temperature

Question 5

What is enzyme inhibition

Answer 5

• A different way of destroying an enzyme’s ability to catalyse a reaction
• A molecule similar in shape to substrate will bind to active site and block active site of the enzyme to the substrate.

Question 6

When is enzyme inhibition helpful

Answer 6

• In drugs, eg painkillers they can stop the reaction of substrate and enzyme reacting to make a painful substance.

Also penicillin inhibits enzymes that control the building of cell walls in bacteria