Enzymes revision Quiz

What are enzymes?

• Proteins that function as biological catalysts

• Carbohydrates that store energy

• Lipids that form cell membranes

• Nucleic acids that carry genetic information

Which of the following best describes the role of enzymes in chemical reactions?

• They slow down chemical reactions

• They alter or speed up chemical reactions

• They are used up in the reaction

• They prevent chemical reactions from occurring

What happens to enzymes at the end of a chemical reaction?

• They are broken down

• They are chemically changed

• They remain chemically unchanged

• They become inactive permanently

Which of the following is NOT a characteristic of enzymes?

• They are proteins

• They function as biological catalysts

• They are used up in reactions

• They remain unchanged after reactions

According to the "lock and key" hypothesis, what does the "key" represent?

• The enzyme

• The substrate

• The product

• The active site

Why is it important for enzymes to remain chemically unchanged after a reaction?

• So they can be used again for more reactions

• So they can be broken down for energy

• So they can become part of the product

• So they can change the pH of the solution

Which term describes the point at which an enzyme works best?

• Maximum

• Optimum

• Denatured

• Inactive

Which enzyme is responsible for breaking down starch into maltose?

• amylase

• lipase

• protease

• catalase

What is the main function of digestive enzymes in the body?

• To break down large molecules into smaller, soluble molecules

• To build large molecules from smaller ones

• To transport oxygen in the blood

• To store genetic information

Which enzyme breaks down toxic hydrogen peroxide into water and oxygen?

• catalase

• amylase

• maltase

• lipase