Enzymes Flashcards
what is an enzyme?
a protein that acts as a biological catalyst
what is protein?
A long organic molecule which contains carbon, nitrogen, oxygen and hydrogen. Sometimes known as a polypeptide.
what is a substrate?
The reactant on which an enzyme works.
what is the pH scale?
scale with values from 0 to 14, used to measure the concentration of H+ ions in a solution; a pH of 0 to 7 is acidic, a pH of 7 is neutral, and a pH of 7 to 14 is basic
what does complementary mean?
fitting together well - an enzyme will bind with a complementary substrate (one that fits the active site of the enzyme)
what is an active site?
a region on an enzyme that binds to a protein or other substance during a reaction. Only the correct substrate will bind to the active site
what are optimal conditions?
Best, most desirable or favorable conditions. Enzymes all operate best under quite narrow ranges of temperature and pH.
what is catalase?
an enzyme that catalyzes the breakdown of hydrogen peroxide into water and oxygen.
what is pectinase?
An enzyme that weakens plant cell walls by breaking down pectin
where can pectinase be found?
fruits of plants where they play a natural role in the ripening process
what is cellulase?
an enzyme that weakens plant cell walls by breaking down cellulose
what does denatured mean?
the change the shape of an enzyme so that it can no longer speed up a reaction.
what is a molecule?
a group of atoms bonded together
what is pectin?
a sugar that is present in ripe fruits
what is cellulose?
A substance (made of sugars) that is common in the cell walls of many organisms
what is a catalyst?
a substance that speeds up the rate of a reaction without being used up itself.
what does a catalyst do?
Speed up the rate of a reaction
What is an extracellular enzyme?
an enzyme that is secreted by a cell and functions outside of that cell
what is an intercellular enzyme?
an enzyme that functions within the cell in which it was produced
what is an enzyme-substrate complex
A temporary complex formed when an enzyme binds to its substrate molecule(s).
what is amylase?
Enzyme in saliva that breaks down starch into simpler sugars - produced in the mouth and pancreas
what is iodine solution?
A substance that tests for the presence of starch - it turns blue/black if starch is present.
what is buffer solution?
a solution that has the ability to resist small changes in pH upon the addition of small amounts of either acid or base. It’s pH is constant.
what is Carbohydrase?
enzyme that breaks down starches into sugars
what is Isomerase?
An enzyme that changes glucose (syrup) into fructose (syrup)
what is protease?
enzyme that breaks down proteins - can be used to pre-digest baby foods
what is Lipase?
enzyme that breaks down fat (lipids) into fatty acids (carboxylic acids)
