enzymes SLOP Flashcards
explain what is meant by the ‘turnover number’ of an enzyme
the number of substrate molecules converted per second
what organelle contains catalase in a eukaryotic cell?
peroxisome
catalase is an intracellular enzyme, state its function
breaks down hydrogen peroxide (harmful product of metabolism)
state functions of amylase and trypsin
amylase - digest starch -> maltose
trypsin - digest proteins into smaller peptides
different between lock and key vs inducted fit model
In lock and key, enzyme AS and substrate have complementary shapes.
In inducted fit model, the active site moulds itself around the substrate to give a better complementary fit, producing stable ES complex
explain why enzyme reaction doesn’t increase above 50C?
high temp over optimum cause hydrogen and ionic bonds to break within the protein molecule, changing shape of the active site, so that it’s no longer complementary to substrate
explain why enzymes only work within narrow ranges of pH
because changes in pH change balance of H ions which hold shape of enzymes AS. IF shape of AS changes substrate will not bind
what is a buffer solution
a solution which resists changes in pH by donating or accepting protons
suggest why fungi, plants, and some bacteria have the enzyme urease
to breakdown urea into ammonia - can be absorbed and used to make new amino acids, for protein synthesis
in what ways are metallic ion cofactors different from zinc based prosthetic groups
metallic cofactors bond temporarily, but prosthetic groups are permanently bound to the enzymes active site
state similarity and difference between metallic ion and cofactors
similar - both form temporary bonds with enzyme + both non protein
different - metallic cofactors are inorganic, coenzymes are organic
state the cofactors/prosthetic groups of both amylase and carbonic anhydrase
amylase - chloride ions Cl-
C.A - zinc ion acts as prosthetic group
explain how competitive inhibition reduce enzyme activity
inhibitor molecule has similar shape to that of the substrate and competed for AS directly. It blocks AS and prevents formations of ESCs
explain how non competitive inhibition reduces enzyme activity
attach to allosteric site, changes enzymes tertiary structure = changes shape of AS
describe structure of amylose, including bonds involved and shape
all 1-4 glycosidic bonds, straight helix
