Biology 2.6 Enzyme Action

Enzymes = globular proteins that act as catalysts.

Enzymes as catalysts lowering activation energy

Sucrose + water (substrates) ---> glucose + fructose (products)

For reaction to occur:

• Sucrose and water must collide w/ sufficient energy to alter arrangement of atoms to form glucose and fructose.
• Energy of products must be less than that of substrates.
• Initial boost of energy needed to start reaction. 
• Activation energy = minimum energy needed to activate the reaction.

Enzymes lower the activation energy level, allow reactions to take place at lower temperature.

Enables some metabolic processes to occur rapidly in the human body at 37C.

Enzyme structure

• globular proteins = specific 3D shape from sequence of amino acids.
• only a small region of enzyme is functional = active site, made up of relatively small number of amino acids.
• Molecule on which enzyme acts…