Enzymes - Week 2 Cell Bio

Biological catalysts do what?

• Increase the rate of aa reaction by lowering the activation energy

• Forms transient complexes with substrate molecules

• Lower activation energy

• Changes only the rate at which equilibrium is achieved

What law do enzymes obey?

The 2nd law of thermodynamics

Can enzymes force unfavorable reactions?

Enzymes accelerate an energetically favorable reaction, BUT they cannot force unfavorable reactions to occur (only can make exergonic ones go)

• Cells need to do just that to grow and divide

  • They build highly ordered and energy rich molecules from simple, small ones

  • This requires an INPUT of energy

What is free energy?

The energy that can be harvested to do work or drive chemical reactions

• The greater free energy, the greater the amount of disorder in the universe

• Chemical reactions proceed only in a direction that leads to a loss of free energy