B4 - Enzymes Flashcards
what are enzymes?
Enzymes are proteins that function as biological catalysts. They are made in all living cells.
what are enzymes like?
Enzymes are like catalysts and can be used over and over again because they are not used up during the reaction and only a small amount is needed to speed a reaction up.
how do enzymes work?
The enzyme works with a substrate. The enzyme has an active site which is complementary to the shape of the substance, they fit together like a lock and a key. Once substrate binds to the active site, it is changed into the products and they are released.
what is the connection between enzymes and temperature?
A rise in temperature increases the rate of the chemical reactions. A fall in temperature slows them down. Increasing the temperature increases the kinetic energy of particles, which means there are more collisions and thus a higher rate of reaction. However, there is an optimum temperature which is 50 °C. Above this the active site becomes denatured and the enzymes stop working. Enzymes work best in the optimum temperature.
what is the connection between enzymes and pH?
Enzymes have different optimum pH’s depending on where they’re found in the body. A pH which is too high or low for a specific enzyme will cause it to denature. and a pH which is too low will cause the active site to denature. Enzymes work best in the optimum pH.
