1. KEY CONCEPT Enzymes are catalysts for chemical reactions in living things.

2. Catalysts are substances that speed up chemical reactions.
1. decrease activation energy
2. increase reaction rate

3. ENZYME
ARE CATALYSTS
ARE PROTEINS (made of ELEMENTS: CHON)
NEEDED FOR ALMOST ALL PROCESSES IN OUR BODIES
CAN BE RE-USED AND RECYCLED
TYPICALLY END IN THE SUFFIX –ASE
AMYLASE
LACTASE .

4. HOMEOSTASIS AND ENZYMES
Disruptions in homeostasis can prevent enzymes from functioning.
Enzymes function best in a small range of conditions. Enzymes are affected by:
Change in temperature
Change in pH
Concentration of enzyme
An enzyme’s function depends on its structure.

5. ENZYME STRUCTURE AND FUNCTION:
An enzyme’s structure allows only certain reactants to bind to the enzyme.
substrates (reactants)
enzyme
Substrates bind to an enzyme at certain places called active sites.
SUBSTRATES: Bind to an
enzyme at certain
places called
active sites

6. The lock-and-key model helps illustrate how enzymes function
The lock-and-key model helps illustrate how enzymes function. Enzyme is lock, substrate is key.
Substrates bind to an enzyme at certain places called active sites.
The enzyme brings substrates together and weakens their bonds.
The catalyzed reaction forms a product that is released from the enzyme.