3. Enzymes

Question 1

What is a catalyst?

Answer 1

A catalyst increases the rate at which chemical reactions occur, but remain unchanged, or are unaffected by the reaction.

Question 2

What is activation energy?

Answer 2

The minimum energy required for a successful reaction. As chemical reactions require bonds to be broken to reform the products.

Question 3

How do enzymes catalyse reactions?

Answer 3

By lowering the activation energy required for a successful reaction. This means the reaction can occur at a lower temperature.

Question 4

How do enzymes lower the activation energy required for a successful reaction?

Answer 4

Help to align the reactants through the formation of enzyme substrate complexes. This means collisions will occur between specific parts of the molecules involved in the reaction, so bonds can break and reform more efficiently, so less activation energy is needed.

Question 5

Enzymes _________ the breakdown of _________ molecules into _________ molecules by _________. These can then be _________ and ____________. This can occur at ______ temperature. (____)

Answer 5

Enzymes CATALYSE the breakdown of LARGE, INSOLUBLE molecules into SMALL SOLUBLE molecules by HYDROLYSIS. These can then be ABSORBED and ASSIMILATED. This can occur at BODY temperature. (37^o C)

Question 6

What are enzymes?

Answer 6

Enzymes are globular proteins that act as biological catalysts.