1.6 Flashcards
what is cell metabolism
the collective term for the thousands of biochemical reactions that take place in a living cell
what are catabolic reactions
degradation, releases energy
what are anabolic reactions
synthesis, require energy
why are some metabolic pathways reversible and irreversible
to allow the process to be controlled precisely
why do some metabolic pathways contain alternative routes
to allow steps in the pathway to be bypassed
what indicates the the rate of a chem reaction
the amount of chemical change that occurs per unit of time
what is the chemical change
the joining together or breaking of reactant molecules
what is the energy needed to break chemical bonds
activation energy
what are enzymes
biological catalysts which speed up the rate of reactions by lowing the energy needed to form the transition state
what do enzymes allow biochem reactions to do
happen at low temperatures
what is the induced fit
when the substrate binds to the active site and it changes shape slightly to better fit the substrate
what is high affinity
a chemical attraction to the active site
what does an induced it do
lowers the activation energy by weakening the chemical bonds of the substrate molecule
do products have a low or high affinity to the active site
low
does the enzyme change during induced fit
no
how are the products of an enzyme reaction able leave the active site
they don’t have a high affinity which allows them to leave
how does the induced fit lower the activation energy
by weakening the chemical bonds of the substrate molecules
what determines the orientation of reactions
the shape of the active site
what are the effects of substrate concentration
as the substrate concentration increases, the rate of enzyme reaction also increases until all active sites are occupied by substrates then it remains steady
what effects the direction of enzyme reactions
substrate and product concentrations
what happens if product concentration is too high
the enzyme can work in reverse to convert some of it back to the substrate
what are the 3 inhibitors
competitive
non competitive
feedback
where do competitive and non competitive inhibiters bind
competitive - at the active site
non competitive - away from the active site
which inhibitors can be reversed by increasing substrate concentration
competitive
