Enzymes Flashcards
What are enzymes?
Enzymes are biological catalysts - they speed up reactions in biological reactions. These are called metabolic reactions, they include digestion of food molecules, respiration and photosynthesis.
what affects enzymes?
temperature
pH
how does temperature affect enzymes?
As the temperature increases the rate of reaction speeds up. This is because the molecules move faster as they have more heat energy. The temperature at which enzymes work fastest is their optimum temperature. Above the optimum temperature the rate of reaction slows down. This is because the enzyme has been denatured.
what is a protein enzyme?
molecules with a 3D shape containing an active site
all enzymes are proteins.
what is a catalyst?
Unchanged by the reaction. Each enzyme molecule can be used over and over again.
what is a specific enzyme?
Each enzyme can only convert one kind of substrate molecule. This is because the active site of the enzyme molecule has to be exactly the right shape to allow a substrate molecule to fit into it.
what is the active site of an enzyme?
The part of the molecule that fits the substrate. If the enzyme is too hot, the active site changes shape and the enzyme has been denatured. If the active site changes shape it cannot fit the substrate.
how do enzymes work?
Enzyme molecules are proteins. They have a specific shape to fit the molecules they react with. Enzymes are specific - they work on specific substrate molecules - amylase only breaks down starch.
which enzyme breaks down starch?
amylase
what does starch get broken down into?
maltose
which enzyme breaks down maltose?
maltase
what does maltose get broken down into?
glucose
