Enzymes Flashcards
(25 cards)
in living cells, biomolecules can be built up to form larger biomolecules. what is the name for this
anabolism
name the part of a lipid molecule that is replaced by a phosphate group to form a phospholipid
fatty acid
why would an enzyme give a positive result for the biuret test
they are proteins
enzymes catalyse reactions by lowering activation range of an enzyme. explain activation range
the energy needed to start a reaction
most enzymes exhibit optimal activity at ph 7. give one enzyme with a significantly different ph
pepsin in stomach at ph 2 (acid stomach conditions0
investigation on the effect of ph and temp on the rat of enzyme action ;
name enzyme used and the reaction it catalyses
catalase converts hydrogen peroxide to water and oxygen
when investigating the effect of temp on enzyme action explain how you kept the temp below 10 degrees
use of water bath with a thermometer
suggest why buffer is used in the experiment investigating effect of temp on enzyme action
to keep ph constant
when investigating the effect of ph on enzyme activity explain how ph would be altered in the absence of a buffer
add vinegar or bread soda
explain how you measured the enzyme activity for catalase
volume of foam produced per 2 mins
explain why there is a fall of enzyme activity after 40 degrees
human enzymes work best at 37 degrees, at temperatures higher they become denatured
explain enzyme specificity with reference to the active site
only one substrate matches the shape of the active site
what happens to the activity of enzymes when placed in a medium outside their optimum ph
activity is reduced as the shape of the active site changes and the enzyme becomes denatured
name two substances used to immobilise enzymes
sodium alginate and calcium chloride
give two advantages of using immobilised enzymes
they are reusable and easy to separate from the product
with reference to the active site of an enzyme explain what is meant by denaturation
the enzyme changes shape and the active site will no longer accept a substrate molecule
what are immobolised enzymes
enzymes that are attached or fixed to each other or an inert material
how did you immobilise enzymes
trapped in alginate beads - sodium alginate + yeast hardened by calcium chloride
state an industrial application of immobilised enzymes
the production of lactose free milk
explain the term metabolism
the sum of all the chemical reactions in an orgnism
give a factor other than ph that affects enzyme activity
temperature
explain the term optimum activity
the conditions under which an enzyme works at its best rate
effect of ph on the rate of enzyme activity
name the enzyme used
catalase
effect of ph on the rate of enzyme activity
state the source of enzyme used
the substrate
celery
hydrogen peroxide
