Enzymes 1

The video tutorial explains the role of catalysts in chemical reactions, focusing on enzymes as biological catalysts. It highlights the critical role of enzymes in metabolism, enabling reactions at lower temperatures. The classification of enzymes by the IUBMB into six classes is discussed, along with the structure and function of enzymes, including the active site and cofactors. The enzyme-substrate interaction is explained through models like the lock and key and induced fit, emphasizing how enzymes lower activation energy to facilitate reactions.

What is the primary role of enzymes in biological systems?

• To catalyze biochemical reactions

• To act as structural components

• To store genetic information

• To provide energy for reactions

Which class of enzymes is responsible for catalyzing oxidation-reduction reactions?

• Isomerases

• Oxidoreductases

• Hydrolases

• Transferases

What is the significance of the four-digit enzyme commission number?

• It indicates the enzyme's molecular weight

• It classifies the enzyme's function and specificity

• It shows the enzyme's pH range

• It denotes the enzyme's temperature stability

What is the role of a cofactor in an enzyme?

• To act as a substrate

• To assist in the enzyme's catalytic activity

• To provide structural support

• To inhibit enzyme function

What is a ribozyme?

• A protein-based enzyme

• A lipid molecule

• A carbohydrate structure

• An RNA molecule that acts as a catalyst

Which model suggests that enzymes change shape to accommodate substrates?

• Lock and key model

• Induced fit model

• Fluid mosaic model

• Allosteric model

What is the primary function of an enzyme's active site?

• To bind substrates and facilitate reactions

• To bind cofactors

• To store energy

• To transport molecules

What is the substrate in an enzyme-catalyzed reaction?

• The enzyme itself

• The product of the reaction

• The reactant upon which the enzyme acts

• The cofactor

How do enzymes affect the activation energy of a reaction?

• They increase it

• They decrease it

• They have no effect

• They eliminate it

Why are enzymes crucial for metabolic reactions in cells?

• They provide energy for reactions

• They increase the temperature of reactions

• They lower the activation energy required

• They act as reactants