Enzyme action

Describe how you would determine the concentration of creatinine in a urine sample using your calibration curve

1. Use same volumes of solution as used in producing calibration curve

2. Add creatinine detecting solution

3. Read off concentration against absorbance/ transmission value obtained

Describe how to produce a calibration curve

1. Use distilled water and creatinine solution to produce dilutions series

2. Add creatinine detecting solution to each test tube

3. Use a constant volume of a solution

4. Record absorbance/ transmission of solutions using a colorimeter

5. Plot dilution/ concentration of creatinine solution against absorbance/ transmission 

What is the alosteric site

Site that is not the active site, that molecules can fit into and cause the structure of the enzyme and shape of the active site to change 

Activation energy 

Actually the energy required to form the transition state 

Catalyst

Provides an alternative pathway by reducing the activation energy

Why are enzymes effective in tiny quantities

They dont get used up so you only need a small amount

Describe why changing one of the amino acids that make up the active site could prevent the enzyme from functioning 

The changed amino acid may no longer bind to the substrate which will then not be positioned correctly if at all in the active site 

Explain why changing certain amino acids that are not part of the active site also prevents the enzyme from functioning 

The changed amino acids may be one that forms hydrogen bonds with other amino acids 

If the new amino acids does not form hydrogen bonds the tertiary structure of the enzyme will change including the active site so that the substrate may no longer fit 

Enzymes

Enzymes are tertiary structure proteins which catalyse reactions by lowering the activation energy

Whilst enzymes are relatively large molecules, it is only a small part of the enzymes that attaches to a substrate to catalyse a reaction This site is known as the active site

This active site is specific and unique in shape due to the specific folding and bonding in the tertiary structure of protein

Due to the specific active site, enzymes can only attach to substrates that are complementary in shape