mostly about factors affecitngenzymes Flashcards
• the general factors that impact on enzyme function in relation to photosynthesis and cellular respiration: changes in temperature, pH, concentration, competitive and non-competitive enzyme inhibitors
What 6 factors affect enzymes
- Temperature
2.PH
3.Noncompetiive inhibiton
4.concentration
5.competiive inhibiton
6.coenzymes
How are enzymes affected by cold temperautres
asthere is less kinetic energy, substrate molecules to to moveslower and collide less freuqnetly, resulting in enzymes expeirnece freezing & little to no activity.
How are enzymes affected by optimal temperautres
Optimaltemperatures cause enzymes to have greater kineticenergy and collide with eachtoher more frequently, allowing for more enzyme substrate complexs toform
How are enzymes affected by hot temperautres
Enzymes are affectedby hot temperatures:
1.Enzymes denature due tohigh temperatures kinetic energy is very high n collisons, between enzymes and the substrate.
2.This results ina conformational change inthe active siteof the enzyme, causign thesubstrate to no longer fit
- the rate of reaction will drop rapidly after reaching optimal temperature
What happens toanenzymewhen PH becomes tooacidic or alkaline
enzymes denature
How does increaisng substrateconcentration affect enzyesm
Initally. rate of reaction increases
then due tohigh kinetic energy levels, the number of collisons will increase between enzyme and the substrate, greater enzyme substrate complexes form
eventually, so much ofthesubstrate binds withtheactivesite thatall theactive site onthe enzyme will become saturated, resulting inthe rate of reaction plateau
Ifsubstrate concentration islow, how areenzymes affected
(also means enzymecocenntrationis higher)
The chemical reactiowill occur morerapidly because more enzyme molecues arepresent, reuslting in more active sitesto be avablaible for substrateto bind to.
However, once enzymes reachtheir saturation point,the point of reaction will plateau
when does compeititve inhibiton occur
How does competitive inhibition cause no reaction to occur
inhibitor molecule binds to the active site and blocks the active site. Asa rsult, the enzyme becomes saturated with substrate.
Why does a competiitve inhibitor have a shape complemeatnary to the substrate
to block the active site
Whendoes non comepetiive inhibition(also known as allosteric inhibition)occurs when
occurs whenn an inhibitor binds to an enzyme at(an allostericsite)
howdoesa conformational change occur
occurs whenn an inhibitor binds to an enzyme at a site other than theactive site(an allostericsite)
Function of a conformationalchange in active site
conformationall change prevents thesubstratefrom binding totheactive site, ulitmately preventing the reaction from occurring
What do coenzymesdo during a chemical reaction
During the reaction, the coenzymes bind to the active site, donates energy or molecules, and then cannot immediately reused
What do coenzymes do after a reaction
the coenzymes leave the enzyme and are receycledafter accepting more energy, so that it can assistinmore reactions
explain the crucial processfor biochemicalpathwya knwon as cycling of co enzymes
1.During the reaction, the coenzymes bind to the active site, donate energy or molecules, and then cannot immediately reused
2.the coenzymes leave the enzyme and are recycled after accepting more energy so that it can assist in more reactions
Cofactor
a molecule that assists in enzyme functioning
some enzymes require assistance fm a cofactor
How are the coenzymes a subset to a cofactor
the coenzymes leave the enzyme and are receycledafter accepting more energy, so that it can assistinmore reactions
EXMAPLE of a coenzyme
B vitamins AS They catalyse the celluar physiological chemical reactions
compare how heat, PH affectenzymes
high heat causesenzymesto denature, however low heat has no affect on enzymes
Extreme high or low PH cause enzymedneaturation
What is the lock and key module-3 marks
The lock refers to the active site, whilst the key refers to the substrate both of which are complementary to each other, therefore together like a lock and key. The binding of the lock and key results in a series of chemical reacts.
Why may the lock and key model not becorrect(argueagainst)
The lock andkey model is unrealisitic because it is unlikely that the substrate and active site have anexact complementary shape
What is the induced fit model
l states a substrate binds to an active site and both change shape slightly, creating an ideal fit for catalysis
compare the lock and key model to the induced fit model
Lock and key modelstates that the active site and substrate which act asthe lock and key are permantely shapedcomplementary to eachother, whereas the induced fit modelstates thatthe substrate and active site are of a similar shape, andtherefore mold shape to becomecomplementary prior to binding.