Enzyme fin the blank
enzymes act as vitamins
are a type of
- which speed up metabolic reactions. they
protein
amino accas
- molecule, which are polymers of smaller
joined into a long chain. these chains coil into
a_spiral
and then fold up to produce a particular shape. their
activity depends upon their shape, which is specic
they are
relatively fragile and
- in water. the shape can be destroyed by
various factors, which include changes in ph
tempahce
solvents and metal lons. each enzyme is
to a particular reaction
te. it will catalyze only one reaction. enzymes are now named according to who
they act on e. g. urease catalyses the hydrolysis (splitting) of urea but older names
do not reflect this. one model of the way enzymes work is the lock and
- theory. the enzyme has a shape on it's surface, called
the active
- site, which fits the substrate molecule (the one it acts on).
the substrate binds into this site, is held by a particular charge pattern, reacts and
then leaves as the product(s).as the enzyme is not changed in each reaction it can
act over and over again and a few enzyme molecules can catalyze many
substale molecules. the number of molecules that one enzyme can
catalyze in a minute is called the
__number. this can be
from 15 to 36 million. many enzymes need another molecule or metallon, called a
cofactor, to be present to work. many
are cofactors to
enzymes (and are called coenzymes). amounts of enzymes are regulated in various
ways so that reactions do not get out of -
e. g. by a gene
turning off production, by other enzymes in feedback mechanisms and by hormones.
control
protein
turnover
cubetrate