Enzymes Flashcards
How are enzymes classified?
Enzymes are classified by the kind of chemical reaction they catalyse.
What is the role of enzymes?
The basic role of enzymes is the increase of the rate of reaction. The enzyme reacts with only one reactant to produce products.
What are products?
Products are substrates converted by enzymes
What is a substrate?
A substrate is the chemical of interest that an enzyme acts upon
What is the active site of enzymes?
The active site of enzymes is the place where the substrate binds and at which catalysis occurs.
What occurs when the amount of substrate increase in an enzyme?
When the substrate concentration increases when the enzyme is kept constant, the reaction velocity will increase until it reaches a maximum.
What is the make up of enzymes?
The make up of enzymes are on the majority, subunits of proteins Those who don’t contain proteins usually consist of small catalytic RNA molecules. Many enzymes also contains a co-factor to help with a reaction
What is a catalyst?
A catalyst is a substance that increases the rate of a chemical reaction without itself undergoing any permanent change. An example is hydrogen peroxide.
What is the lock and key theory?
The Lock and Key Theory talks about how the lock is the enzyme and the key is the substrate. Only the correct key can fit into the correct lock.
What is activation energy and how are enzymes involved?
Activation energy describes the minimum energy which must be available to a chemical system with potential reactants to result in a chemical reaction. Enzymes are involved by lowering the activation energy of a chemical reaction.
What are enzyme inhibitors?
Enzyme inhibitors are molecules that interact with an enzyme to prevent the enzyme from working in an normal manner. There are a variety of enzyme inhibitors including:
. Nonspecific (denatures all enzymes) eg temperature
. Specific (denatures a single enzyme) eg drugs/antibiotics
. Competitive (competes with the active site and prevents reaction) eg ethanol for menthol poisoning
What are some examples of enzymes?
. Amylase (converts starch to maltose; can be found in the saliva)
. Pepsin (converts proteins to polypeptides; can be found in the stomachs mucous membrane)
. Lipase (converts fats to fatty acids and glycerol; can be found in the pancreas)
What is the pH optimum of enzymes?
. Lipase (pancreas) pH 8.0 . Lipase (stomach) pH 4.0-5.0 . Lipase (castor oil) pH 4.7 . Pepsin pH 1.5-1.6 . Trypsin pH 7.8-8.7 . Urease pH 7.0 . Invertase pH 4.5 . Maltose pH 6.1-6.8 . Amylase (pancreas) pH 6.7-7.0 . Amylase (malt) pH 4.6-5.2 . Catalase pH 7.0
What is a coenzyme?
A coenzyme is a non-protein compound that is necessary for the functioning of an enzyme.
What is optimum efficiency?
Optimum efficiency is a term used to describe the condition when an enzyme is producing the best it can with the lowest temperature or pH possible.
