Enzymes In Action Flashcards
When do biological washing powers don’t work?
At high temperatures and extremes of pH
Describe how people with diabetes test their urine for the presence of glucose
- benedicts test
- large sample of blood or urine
- heated with benedict’s reagent
- if the blue reagent turns brick red then sugar is present
Recall how some enzymes can be immobilised
In gel beads, on reagent sticks
What can immobilised enzymes on reagent sticks be used to measure?
Glucose levels in the blood
Describe the enzymes in biological washing powders:
- amylases
- lipases
- proteases
- to digest the carbohydrate starch
- to digest fat and remove fatty stains
- to digest protein and remove protein stains
Explain why biological washing powders work best at moderate temperatures
Enzymes work best at moderate temperatures between 37-40°C and at a neutral pH. Enzymes are denatured by high temperatures.
Explain why the products of digestion will easily wash out of clothes, in terms of their solubility
The products of digestion are soluble, so they dissolve in the water and wash out of the clothes more easily than the stain.
Explain why biological washing powders may not work in acidic or alkaline tap water
In areas that have very acidic or alkaline tap water, enzymes don’t work so well. This is because the shape of the enzymes is changed by the extreme pH and they can no longer function.
Describe how sucrose can be broken down by the use of an enzyme called sucrase (invertase)
Sucrose can be broken down into smaller sugars using sucrase enzyme (invertase).
What happens when sucrose is broken down by enzymes?
The product is much sweeter making it useful to the food industry
Explain how foods are sweetened using invertase
- invertase converts sucrose into glucose and fructose
- theses sugars are much sweeter than the sucrose
- foods can therefore be sweetened without adding so much sugar
Describe how enzymes can be immobilised in gel beads
- by mixing the enzyme with alginate
- by dropping the mixture into calcium chloride solution
Explain the advantages of immobilising enzymes
- the mixture not becoming contaminated with the enzyme
- immobilised enzymes in alginate beads can be used in continuous flow processing
Explain the condition of lactose intolerance
- they cannot produce the enzyme lactase
- so bacteria in the gut ferment lactose
- fermentation produces diarrhoea and wind
Explain the principles behind the production of lactose-free milk for people with lactose intolerance
- immobilised lactase converting lactose in milk into glucose and galactose
- these simple sugars can then be absorbed
