Enzymology and Thermodynamics

Question 1

Delta G and Enzymes

Answer 1

Enzymes don’t change a reactions delta G value

Don’t change whether a reaction is endo or exothermic

Instead, lower energy of transition state

Question 2

Transition State

Answer 2

Unstable state that reactants must pass through to become products

Question 3

Factors Affecting Enzyme Function- Temperature

Answer 3

Temperature

• Increases rate of reaction
• If temperature is ourside tolerable range, can affect chemical bonds in active site
• Very high temperatures can denature ezyme

Question 4

Factors Affecting Enzyme Function- pH

Answer 4

Active site a.a. residues have acidic of basic properties

Changes in pH can affect these residues and make it difficult to bind

Question 5

Cooperativity

Answer 5

When one substrate attaches, enzyme becomes more receptive to additional substrates

i..e Hb and oxygen binding

Question 6

Entropy

Answer 6

Degree of randomness or disorder in system

Always increasing in the universe

Question 7

First Law of Thermodynamics

Answer 7

Energy cannot be created or destroyed, only changed

Question 8

Second Law of Thermodynamics

Answer 8

Every energy transfer that takes place increases entropy of the universe

Reduces amount of usable energy available to do work