Bio 93 Midterm 2

Catabolism

Breaks down complex molecules into simple ones, releasing energy

Anabolism

Creates complex molecules from simple ones, requiring energy

Exergonic reactions

- Energy is released

- Spontaneous reaction

- Change in G is less than 0

Endergonic reactions

- Energy is absorbed

- Not a spontaneous reaction

- Change in G is greater than 0

Hydrolysis

Breaking down of a phosphate bond releases energy

ATP structure

ribose, adenine, and a phosphate group

Energy coupling

cell groups exergonic ATP hydrolysis to drive endergonic cellular work

Enzymes as catalysts

Speed up reactions by lowering the activation energy required to reach the transmission state.

Enzymes do NOT

Change the overall free energy change

Enzymes are NOT

consumed in the reaction

Cofactors

are inorganic metal ions

Coenzymes

are organic molecules (e.g., vitamins, ATP)

Enzyme inhibitors

competitive and noncompetitive inhibitors

Competitive inhibitor

Binds to the active site, competing with the substrate (can overcome by adding substrate)

Noncompetitive inhibitor

Binds to an allosteric site from the active site, changing the enzymes shape (cannot overcome by adding more substrate)