Internal Membranes & Enzymes (PPT 8) [U1/ T1]

Question 1

What are enzymes?

Answer 1

Enzymes are organic catalysts that are made of protein

Question 2

Define catalyst?

Answer 2

• Making something happen

Question 3

What is the active site?

Answer 3

A cleft, groove or pocket on the surface of an enzyme

Question 4

What is a substrate?

Answer 4

The substance that an enzyme binds to

Question 5

Why can’t enzymes bond with any random substrate?

Answer 5

Because enzymes are substrate specific, this can be high or low specificity.

Question 6

How do enzymes work?

Answer 6

By bringing substrates together to break down an existing bond and form new ones, creating a new product.

Question 7

What are the features of the lock and key model?

Answer 7

• Shape of the active site is not flexible

- Will not move with the substrate.

Question 8

What are the features of the induced fit model?

Answer 8

• Shape of active site is flexible

- Will move with the substrate

Question 9

What are the features that the lock and key, and induced fit theory have in common?

Answer 9

• Both theories on how enzymes work

- Include a substrate, active site, and creation of new products.

Question 10

What is activation energy?

Answer 10

Activiation energy is the amount of energy required for a reaction to occur.

Question 11

What effect do enzymes have on the activation energy?

Answer 11

They lower the activation energy so they reactions can occr quicker and more often.

Question 12

What factors can affect the optimum working condition of an enzyme? Why?

Answer 12

• Temperature
• pH
• Because a pH or temperature too far off the optimum condition of an enzyme alters the active shaoe, meaning the enzyme can no longer complete its job.

Question 13

Name 2 limiting factors that can determine how well an enzyme can work?

Answer 13

• Temperature
• pH
• Substrate concentration
• Enzyme concentration

Question 14

What are the two types of inhibitors?

Answer 14

• Competive inhibitors

- Non-competive inhibitors

Question 15

How do competitive inhibitors affect an enzymes reaction rate?

Answer 15

• The inhibitor competes with the substrate to bind to the active site. This prevents substrates from binding and stops the reaction from occuring

Question 16

How do non-competitive inhibitors affect an enzymes reaction rate?

Answer 16

• The inhibitor does not interfere with the active site. Rather they bind to the enzyme and alter its shape, stoping the substrate from bonding due to the level of specificity required.