S2 Enzymes

The diagram shows an enzyme catalysing the break down of a large molecule. Which letter is the active site?

• P

• Q

• R

• S

The diagram shows an enzyme catalysing the break down of a large molecule. Which letter denotes the substrate?

• P

• Q

• R

• S

The diagram shows an enzyme catalysing the break down of a protein molecule. What is R?

• Product

• Substrate

• Protein

• Enzyme

Many enzymes do not work at temperatures above 60 °C. Which statement explains this?

• Product molecules are not made because the active site has changed shape and no longer binds to the substrate.

• Product molecules change shape so they do not fit into the active site.

• Substrate molecules are moving too fast.

• There are too many collisions.

Which graph shows the effect of temperature on the activity of an enzyme?

• A

• B

• C

• D

The graph shows how enzyme activity is affected by temperature.

How can the change in activity between 40 °C and 55 °C be explained?

• Heat has killed the enzyme.

• The enzyme has been used up.

• The reactants are moving faster.

• The substrate is less likely to fit into the active site.

What is a characteristic of all catalysts?

• They are broken down in the reaction.

• They are made of protein.

• They are not changed by the reaction.

• They do not change the rate of the reaction.

Which process involves the release of energy from food substances in all living cells?

• breathing

• nutrition

• respiration

• digestion

Tags

NGSS.MS-LS1-7

The temperature of an enzyme-controlled reaction is increased by 10°C.

How does this affect the rate of reaction?

• It always increases the rate.

• It always decreases the rate.

• It may increase or decrease the rate.

• It has no effect on the rate.

Tags

NGSS.HS-LS1-3

The graph shows how the rate of an enzyme-controlled reaction changes with temperature. What is happening within the temperature range marked X?

• The enzyme is becoming denatured.

• Fewer collisions are happening.

• The substrate fits into the active site.

• The reaction is occurring at the optimum temperature.