8.1  Metabolism

big ninja

Essential Idea:

Metabolic reactions are regulated 

in response to the cell’s needs


  • Metabolic pathways consist of chains and cycles of enzyme-catalysed reactions
  • Enzymes lower the activation energy of the chemical reactions that they catalyse
  • Enzyme inhibitors can be competitive or non-competitive
  • Metabolic pathways can be controlled by end-product inhibition


  • End-product inhibition of the pathway that converts threonine to isoleucine
  • Use of databases to identify potential new anti-malarial drugs


  • Calculating and plotting rates of reaction from raw experimental results
  • Distinguishing different types of inhibition from graphs at specified substrate concentration