Ensymes - Uinit 3 AOS 1

Question 1

enzymes

Answer 1

• proteins which catalyses chemical reactions
• they lower the activation energy required to initiate a reaction by weakening the bonds of the substrate
• less energy is required to make the reaction occur, therefore increasing the rate of reaction

Question 2

active site

Answer 2

• an area on an enzyme were the substrate binds to
• it has a unique shape and charge which is complementary to its substrate

Question 3

substrate

Answer 3

• the substance being acted on by the enzyme
• they bind to the active site on an enzyme

Question 4

activation energy

Answer 4

• the energy required to initiate a reaction

Question 5

catabolic reaction

Answer 5

• releases energy and breaks molecules down into smaller ones
• exergonic

Question 6

anabolic reaction

Answer 6

• requires energy to make larger molecules from smaller ones
• endergonic

Question 7

factors that affect enzyme activity

Answer 7

• temperature
• ph
• concentration
• enzyme inhibiters

Question 8

temperature

Answer 8

• reaction increase with temperatures molecules have greater kinetic energy
• above optimal temperature, hydrogen bonds in tertiary and quaternary structure break due to increased vibrations in molecules. this causes the protein to denature and the active site to change (permanent)
• below optimal temperature, enzyme activity decreases as there is less kinetic energy and the enzyme may freeze (not permanent)

Question 9

ph range

Answer 9

• enzymes have an optimal ph range
• below or above this may casue the enzyme to denature
• confirmational change so the enzyme will no longer be complementary to its substrate
• can also change the charge of the active site

Question 10

concertation

Answer 10

• substrate concentration - as substrate concentration increases, the rate of reaction will increase to a certain point until the enzymes are saturated in the substrate
• enzyme concentration - as enzyme concentration increases, the rate of reaction increases as there are more active sites for the substrate to bind to. it will eventually plateau

Question 11

enzyme inhibition

Answer 11

• enzyme inhibiters are molecules that bind to an enzyme, preventing it from performing its function

Question 12

competitive inhibition

Answer 12

• inhibiters bind to the active site so that the substrate cannot bind to it

Question 13

non-competitive inhibition

Answer 13

• an inhibiter binds to the allosteric site, causing confirmational change of the active site so the substrate can no longer bind to it

Question 14

allosteric site

Answer 14

• a binding site on enzymes where molecules other than the substrate can bind to

Question 15

reversible inhibition

Answer 15

• the bonds formed between the enzyme and the inhibiter are weak and so can be broken
• the effect of these inhibiters are not permanent
• can slow does the rate of reaction

Question 16

irreversible inhibition

Answer 16

• inhibiter will form string bonds with the enzyme
• it is permanent so the enzyme is not able to bind with any substrate.