Studied by 17 people
digital reading
5- A(n) ________ is given of the glucose concentration in the sample.
Environmental factors
________, such as temperature and pH, can denature and permanently alter the shape of enzymes.
Non competitive inhibitors
________ can also bind irreversibly and reversibly, irreversibly deactivating the enzyme.
substrate concentration
An increase in the ________ reduces the effect of these inhibitors, as more substrate increases their chances of successfully beating the inhibitor for the enzyme.
excess OH
At a high pH, ________- ions neutralise positive charges.
Percentage increase
________ in mass= (increase in mass (initial mass- final mass) ÷ initial mass) x 100.
Enzymes
________ only catalyse energetically favourable reactions that would happen without their involvement.
They are globular proteins
tertiary structure with hydrophilic R groups on the outside, making them soluble
This is due to the differing behaviour of enzymes
they can fit either model more closely
Activation energy is the minimum energy required for a reaction
to break the existing bonds and form new ones
At this temperature, the increased kinetic energy causes vibration to increase to the point is breaks the hydrogen bonds, denaturing the enzyme
altering the active site so the substrate cannot fit
At a high pH, excess OH
ions neutralise positive charges
Percentage increase in mass = (increase in mass (initial mass
final mass) ÷ initial mass) x 100
Rate of production (mg min-1) = increase in mass (initial mass
final mass) (mg) ÷ time (mins)
The opposite is also true
an increase in inhibitors lowers the reaction rate
These bind to the enzyme at an ‘allosteric site‘
a site other than the active site, therefore they do not compete with the substrate
1
The reactants are allowed through the semipermeable membrane, in glucose detection this is glucose and oxygen
2
Enzyme-substrate complexes are formed between glucose oxidise and glucose
3
The product is made, gluconic acid and hydrogen peroxide
4
This product is detected by the electrode, which converts the chemical energy to electrical
5
A digital reading is given of the glucose concentration in the sample
Inhibition
Decrease in the rate of an enzyme controlled reaction.
Competitive
Inhibition that binds at the active site.
Non-competitive
Inhibition that binds at the allosteric site.
Feedback inhibition
Process where the final product of a metabolic pathways is a non-competitive inhibitor to the first enzyme in the process.
Immobilised
Enzymes that are fixed in position.
Alginate beads
Beads where enzymes can be held in place.
Continuous flow
Technology where enzymes are held in place to constantly catalyse a product, such as lactase and lactose.
Biosensor
When enzymes are used to calculate the concentration of molecules, such as in diabetes detection.
Glucose oxidise
Enzyme used to detect glucose concentration.
Gluconic acid
Product created and detected during glucose detection.
Metabolic pathways
Enzyme controlled reaction sequences.
Anabolic
Reactions that build up molecules.
Catabolic
Reactions that break down molecules
Basal
Metabolic rate when we are at rest.
Enzymes
Biological catalysts that are tertiary proteins and are necessary for organisms to function.
Extracellular
Enzymes secreted by exocytosis and used outside of cells, such as amylase in the mouth.
Intracellular, in solution
Enzymes that act within a solution in a cell, such as glucose synthesis in the stroma.
Intracellular, membrane-bound
Enzymes that act while attached to membranes, such as on the cristae where they transfer molecules necessary for ATP synthesis.
Lock and key model
Enzymes specifically fit one particular substrate perfectly with no alteration needed.
Induced fit
The enzyme is flexible, and changes shape so the substrate can fit and returns to its original shape afterwards.
Activation energy
Minimum energy required for a reaction to occur, lowered by enzymes.
Temperature coefficient
Measure of a reaction’s rate of change if the temperature is raised by ten.
Note 
Flashcard (24)