C1.1 enzymes and metabolism Flashcards
describe what happens when temp is raised a bit with enzymes
increaseses kinetic energy of susbtrate and enzyme
increase chance of collision between enzymes and susbtrates therefore rate increases
low temp has insufficient htemral energy for the activation energy so there is a low rate of reaction
descibre what happens when temp at optimim with enzymes
optimum temp- max rate of reaction
balance between enzyme stability and kinetic energy of reactants
descibre what happens when temp is over optimum with enzymes
rapid decrease in the rate of reaction
destabilises enzymes as the thermal energy disrupts the hydrogen bonds holding the enzyme together
enzyme is denatured (active site loses its shape and activity)
describe effect of ph a bit increased in enzymes
increase in PH (decrease in H+) or decrease in PH (increase in H+)
H+ interact with exposed R groups on active site
changes the charge and solubility of enzyme
enzyme active site changes shape
specifity reduced
decrease in rate of reaction
describe effect of ph at optimum in enzymes
optimum PH= maximum rate of reaction
successful activated E-S complex and therefore reactions occur
moving outside this range results in a dimished rate of reaction
effect of substrate increse a bit in enzymes
increase chance of collisions between enzymes and susbtrates
greater change of forming e-s complexes
increases in rate of reaction
effect of substrate increse at optimum a bit in enzyme
active site begin to become saturated with susbtrate (fully occupied)
new susbtrate must wait for previous reaction to complete and the product to exit the active site
effect of substrate increse after optimum a bit in enzyme
full saturation of the active sites by susbtrate
rate becomes constant for further increase in susbtrate concentration
what is metabolism
the sum of all the chemical reactions that occur within living organisms
how are metabolic reactions controlled
by specific enzymes, because of enzyme specificity many different enzymes are required by living organisms
metabolism can be considered either:
intracellular: occur within a cell such as protein synthesis and cellular respiration
extracellular: occur outside a cell such as cells of pancreas secreting enzymes chemically digest food
metabolic pathways
a series of steps from a starter molecule or precursor toward a final end product
each step is catalyzed by a different enzyme
describe image of metabolic pathways linear
percursor chemical——>intermediate chemical—–> end product
metabolic pathways can either be….
linear or cyclical
anabolic or catabolic
describe image of metabolic pathways cyclical
reactant—-> intermediate —-> intermediate—-> reactant + product
what are examples of cyclic metabolic pathways
photosynthesis and the krebs cycle of cellular respiration
whats an example of linear metabolic pathway
digestion of starch
anabolic pathways
build up complex molecules fro. simpler ones they intake energy and involve reduction/ condensation reactions. an example is photosynthesis
catabolic pathways
break down complex molecules into simpler ones, they release energy and involve oxidation hydrolysis reactionsan example is cell respiration
is heat generation inevitable? and why?
yes it is invetible because mtabolic reactions are not 100% efficient in energy transfer, animals depende on this heat production for maintainence of constant body temp
what do all chemical reactions recquire?
energy to get started as molecules need to collide with enough energy so reactants have bonds broken moecules are reoriented new bonds are formed
what is the initial energy input called
activation energy, which is defined as minimum amount of energy needed to start the reaction, leading to the formation of a high energy intermediate (transition state)