Enzymes and Reactions

The energy needed to start a reaction is called the

• activation energy

• starting energy

• promoting energy

• reacting energy

Tags

NGSS.HS-PS1-4

Enzymes contain a(n) ___ where reactants can bond to react with each other.

• active site

• reaction site

• substrate site

• enzyme site

Once an enzyme has helped a reaction take place, it can then

• be reused for another reaction with the same reactants.

• be broken down.

• be stored in the cell until it is needed again.

• be used to help different reactants go through a reaction.

Some factors can change the shape of an enzyme and when an enzyme's shape has changed it no longer works. When this happens we say that the enzyme has been ___.

• denatured

• altered

• modified

• renatured

Compare the two pathways, which pathway shows the reaction that has taken place with the help of an enzyme?

• Pathway 1

• Pathway 2

• You cannot tell from these graphs.

• Both reactions involved an enzyme.

At the end of this reaction, has energy been released or absorbed?

• Absorbed

• Released

• There is not enough information to tell.

• There is not change in the amount of energy in the system.

Tags

NGSS.HS-PS1-4

Looking at the graph, how would you know which reaction took place with the help of an enzyme?

• The peak for the activation energy is lower.

• The peak for the activation energy is higher.

• There is less energy in the products than the reactants.

• There is no way to really tell which line on the graph shows a reaction that takes place with a reaction.

Tags

NGSS.HS-PS1-4

The graph below shows how the activity of an enzyme changes over a range of pH values. Which of the following conclusions can be drawn from this graph?

• The optimum pH of the enzyme is 6.6.
• The optimum pH of the enzyme is 5.8
• The enzyme’s activity continually increases as pH increases from 5.0 to 9.0
• The enzyme’s activity is greater around pH of 8.0 than around pH of 5.0.

Some bacteria live in hot springs. Their cells contain enzymes that function best at temperatures of 70 °C or higher. At the temperature of 50 °C, how will the enzymes in these bacterial cells most likely be affected?

• The enzymes will be destroyed by lysosomes
• The enzymes will lose their bond structure and fall apart.
• The enzymes will require less energy to function than at 70 °C.
• The enzymes will not increase the rate of reactions as much as they would at 70 °C. 

Tags

NGSS.HS-PS1-5

The diagram below illustrates a biochemical process that occurs in organisms. What is another name for the substance labeled "catalyst"?

• Enzyme
• inorganic compound
• Hormone
• Antibody