Enzymes: How They Work and What They Do

What is an enzyme?

• A type of carbohydrate

• A biological catalyst

• A type of lipid

• A mineral

Enzymes help in the process of (a)   , which involves breaking down food into energy and building materials.

• eating
• metabolism
• respiration

• photosynthesis

Activation energy is defined as

• the energy released in a reaction

• the minimum energy needed for a reaction

• the energy stored in enzymes

• the energy used by products

Enzymes are primarily made of A) carbohydrates B) lipids C) proteins D) nucleic acids.

• carbohydrates

• lipids

• proteins

• nucleic acids

What happens to enzymes after they catalyze a reaction?

• They are destroyed

• They are changed

• They are reused

• They are consumed

Enzymes lower the (a)   necessary to start a reaction.

• activation energy
• temperature

• pressure

• concentration

A. Enzymes facilitate chemical reactions. B. This involves binding with substrate and forming an ES complex. C. A new product is formed. D. The enzyme is part of the new product. WHICH ONE OF THESE STEPS IS FALSE?

• A

• B

• C

• D

What is the typical temperature for enzyme activity in the human body?

• 37°C

• 50°C

• 60°C

• 70°C

Look at the Enzyme Concentration graph. When enzyme concentration is increased, the rate of reaction will eventually (a)   .

• Decrease

• Increase

• level off
• Stop

Read the pH paragraph and graph and choose the FALSE statement.

• Amylase will digest proteins when pepsin gets used up.

• Pepsin and amylase have different pH where they work best.

• Pepsin and amylase work in different parts of the body.

• Amylase prefers a higher (less acidic) pH than Pepsin.