factors affecting enzyme activity Flashcards
explain how catabolism and anabolism are related to metabolism
catabolism is the breaking down of molecules
anabolism is the building up of molecules
reactions involve both breaking down and building up of molecules and metabolism is the sum of all reactions int he body
describe the flow of the composition of a living organism,what makes what in order to form a whole organism
polymers-cells-tissues-organs-organism
why do enzymes only catalyse one reaction
enzymes are very specifc.Each nzyme has a different shaped active site which is complementary to one speecidfic substrate molecule,explaining why they usually catalase one reaction
what are the 4 factors affecting enzyme activity
-ph
-temperature
-enzyme concentration
-substrate concentration
describe why thee rate of reaction is lower at lower teemperature
the lower temp means that molecules have lower kinetic energy thus they mov slower.This results is less frequent successful collision between the active site and the specific subsate so fewer enzyme-substrate complexes are formed thus the rate of reaction is slower
explain why the rate of reeaction is higher at higher temperature
at higher temperature the molecules have more kinetic energy so movie faster.This increases the likelihood that active site and substrate will collide and because the collision has higher energy it also means that there is a higher chance that each collision will result in a reaction,so in an ezyme-substarte complex
-in other words the faster movement of molecules results is more frequent successful collision so more enzyme-substate complex formation which increases the rate of a reaction
what is the definition of optimum temperature of an enzyme
the temperature at which the reaction catalysed by the enzyme is at its fastest
are the effects of high temperature reversible
no they are irreversible
are the effects of low temperature reversible
yes they are reversible
describe the process of denaturation of an enzyme
-As thee temperature increases so does the vibration of an enzyme molecule.This puts a strain on the hydrogen and ionic bonds which maintain the tertiary structure of the enzyme.At certain temperatures they break,this causes the active site of the enzyme to change shape so its no longer complementary to the specific substrate and as a result the substrate can no longer bond and a reaction cant occur
enzyme is said to have denatured
how do you compare graphs
-compare initial rates
-compare when the graph plateaus
describe how a ph above or below the optimum ph will affect enzyme activity
when the ph changes above or below the optimum ph of 7 ,the number of H+ ions or OH- ions increase.The ions interact with the charged R groups of main o acids.This in turn decreases the extent to which they interact with each other.This affects the hydrogen and ionic bonds which maintain the tertiary structure of the enzyme.When they break the active site of the enzyme changes shape and becomes denatured
what thee optimum ph of an enzyme
7,at the optimum ph the shape of the active site of an enzyme is in correct shape
describee the process of renaturation involving ph
when the ph changes slightly from 7 the shape of the active site changes,its no longer complementary to the substrate and the substrate cant bond,however if you return back to optimum ph the active site will restore its original shape ,where its complementary to that specific substrate
what changes to rate of reaction does the increase of enzyme concentration have .Exaplain why
when you increase ethe concentration of enzymes ,the rate of reaction will increase.This is because by increasing the concentration of the enzyme there will be a higher number of active sites available which the substrate can bind to
-result in more frequent successful collisions between active site and the substrate so results in more ESC’S
-thus faster rate of reaction
what is the v max of a reaction
its when the reaction is proceeding as fast as possible,
the rate of reaction has reached its maximum point
describe what is happening at the v max of a reaction involving enzyme concentration and why
- all teh active site of enzymes are occupied by a substrate molecule
-no more ESC’s can be formed as a result , until the products have been released from the active sites of the enzymes
how can we further increase the V max of a reaction
increase the concentration of enzyme or increase the temperature of the reaction
Explain why at some point increase the enzyme concentration does not result in higher V max/rate of reaction
at some point increasing the concentration of a reaction no longer affects the rate of the reaction, this is because the concentration of substrate has become a limiting factor.The concentration of enzyme is in excess so adding more of it will not have a further effect
describe the effects of increasing substrate concentration on the rate of reaction and explain why that is
-increasing the substarte concnetration also increases thee rate of a reaction
-this is because there will be more substrate molecule to fill and bind to the active sites of enzymes
-result in more frequent successful collision,forming more ESCs so increasing the rate of a reaction
explain why at some point increasing the concentration of substrate molecules does not increase the rate of a reaction,has no effect
at some point a point of ‘saturation’is reached where all the present active sites of enzymes have been occupied by specific substate molecules,so the addition of more substrates will not affect the rate of reaction as the enzyme concentration has become the limiting factor
what can we do to increase the rate of the reaction / V max
increase the enzyme concentration
what is Q 10 also known as
temperature coefficient
what does Q 10 show
It shows how much the rate of a reaction when the temperature
increases by 10 degrees
