The Essential Role of Enzymes in Biochemical Reactions

Professor Dave explains enzymes, proteins that catalyze biochemical reactions by lowering activation energy. Enzymes are crucial for biological processes, operating at body temperature and neutral pH. They have specific substrates, fitting like a lock and key, and can induce conformational changes to facilitate reactions. Enzymes are stereospecific and often named with '-ase'. Examples include lactase, which breaks down lactose. Enzymes are categorized by function, such as hydrolases and ligases, and may require cofactors or coenzymes to function.

What is the primary role of enzymes in the body?

• To provide energy for reactions

• To act as structural components

• To catalyze biochemical reactions

• To store genetic information

How do enzymes recognize their specific substrates?

• Through random interactions

• By changing the substrate's chemical composition

• By matching the substrate's shape and functional groups

• By altering their own structure

What is the induced fit model in enzyme activity?

• The enzyme is permanently altered by the substrate

• The enzyme changes shape to better fit the substrate

• The enzyme and substrate do not interact

• The substrate changes shape to fit the enzyme

What happens when a substrate binds to an enzyme's active site?

• The enzyme-substrate complex forms, lowering activation energy

• The substrate is expelled from the active site

• The substrate is immediately broken down

• The enzyme is permanently altered

Why is enzyme activity described as stereospecific?

• Enzymes can bind to any substrate

• Enzymes only bind to one of the mirror image forms of a substrate

• Enzymes change their shape to fit substrates

• Enzymes can catalyze any reaction

Which type of enzyme is responsible for joining two molecules together?

• Hydrolase

• Ligase

• Transferase

• Isomerase

What is the function of a transferase enzyme?

• To oxidize substrates

• To rearrange the spatial configuration of a substrate

• To transfer a functional group between molecules

• To break down molecules

What is the role of cofactors in enzymatic reactions?

• To inhibit enzyme activity

• To assist in enzyme function

• To bind to substrates

• To provide energy

Which of the following is an example of a coenzyme?

• Calcium

• Zinc

• Iron

• Vitamin B12

Why are vitamins important for enzyme function?

• They provide energy for reactions

• They act as cofactors or coenzymes

• They inhibit enzyme activity

• They are structural components of enzymes