Summary of Concept 5.5

Concept 5.5

Notes

• All chemical reactions require activation energy to be put in for the for the reaction to occur.
• Activation energy is often provided through heat.
• Catalysts are compounds that speed up chemical reactions.
• Enzymes are specialized proteins that work as catalysts on an organic scale.
• Catalysts work by reducing the required activation energy.
• Enzymes only catalyze one specific kind of reaction because enzymes only fit the shape of one reactant molecule.
• The reactant that enzymes catalyze are called substrates, which go inside the region of the enzyme molecule called the active site.
• Temperature and pH affect the effectiveness of an enzyme.

Concept Check

1. Explain the role of activation energy in a reaction. How does an enzyme affect activation energy?
Activation energy is the energy required to be inputted for the reaction to occur, otherwise reactions would all occur spontaneously. Enzymes affect activation energy by bringing down the required amount of energy for the reaction to occur.

2. Describe how a substrate interacts with an enzyme.
Subtrates fit inside the part of the enzyme called the active energy, and the enzyme allows it to cause the chemical reaction in a faster manner, through decreasing the amount of activation energy required.