Unit One - Key Area 6 Flashcards
What are metabolic pathways?
chains of enzyme controlled reactions
What are the different steps of metabolic pathways?
irreversible steps, reversible steps and alternative routes
What are catabolic reactions?
the break down of large molecules into smaller molecules and release energy.
What are anabolic reactions?
the build up of large molecules from small molecules and require energy
What factors can control the rate of a metabolic pathway?
temperature, pH and substrate concentration
What is induced fit?
occurs when the active site changes shape to better fit the substrate after the substrate binds
What do enzymes lower and why?
the activation energy required for a reaction because the active site increases the chances of the reaction taking place by: correctly orientating the substrate molecules or correctly holding the substrate molecules within an induced fit
What do substrate molecules have?
a high affinity for the active site which allows the substrate to bind easily.
What do product molecules have?
a low affinity for the active site, and this allows the products to leave the active site and allows the active site to bind again with another substrate molecule.
What does increasing substrate concentration do?
increases the rate of a reaction until all of the active sites are occupied
What determines the overall direction of a reaction?
the concentration of substrate and product molecules
High substrate concentrations promote what?
forward reactions
High product concentrations promote what?
backward reactions
What do inhibitors do?
reduce enzyme activity by stopping an enzyme from binding to its substrate
What do competitive inhibitors do?
bind at the active site preventing the substrate from binding. Competitive inhibition can be reversed by increasing substrate concentration
