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understand the concept of "chemical equilibrium", consider the factors that cause
a shift of balance, to get acquainted with the concepts of "reaction rate constant"
and "equilibrium constant".
The enormous speed of the reactions in living organisms are possible
because they are biological catalysts of high activity - enzymes capable of life
changed during its activity under the influence of various influences that at each
moment the speed of various processes correspond exactly to the body's needs.
It is necessary to find out in what way can change the enzyme activity as it
is influenced by temperature, active reaction medium, formation by metabolism
of various intermediates temperature increase in the range of 0 to 40 - 50 ° C
increases the rate of substrate enzyme conversion (substances reaction which
enzyme accelerates) further temperature increases the activity of enzymes falls
This feature of enzymes called them thermolability. It is because the enzyme
having a protein sur - nature changes its structure at high temperatures -
denatured. The temperature range at which the enzyme exhibits the highest
activity, is called an optimum temperature of the enzyme.
Enzyme activity was significantly dependent on the ratio of concentrations
in the environment of hydrogen and hydroxyl ions, ie, the reaction of the
medium:.. an acidic, neutral or alkaline. For each enzyme, there is a relatively
small range of reaction changes in the environment in which it maintained the
highest activity. Since the reaction medium is characterized by a quantitative
indicator of hydrogen (pH), studying the digestive enzymes, you should pay
attention to the pH in different parts of the digestive system by studying the
intracellular enzymes, to identify the most favorable for their actions the value of
this indicator.
In the regulation of enzyme activity play an important role activators that
enhance the activity of enzymes and inhibitors, which suppress it. Identifying
which substances may be enzyme inhibitors and activators.
The enzyme may be simple or complex protein. Complex enzyme
(holoenzyme) consists of two components: the protein - and the protein-free
apoenzyme - coenzyme; coenzyme of many enzymes can be separated from the
apoenzyme and exist independently. The same coenzyme may be connected with
different apofermentami. This provides a more flexible regulation of
biochemical processes. Apofermentami determined by the specificity of action
of the enzyme, ie. E. Its ability to accelerate the transformation of a certain type
of single substances or groups of substances that are similar in chemical
structure.
The reason lies in the specificity of enzymes that for the enzymatic
reaction must match the spatial configuration of the enzyme and substrate
molecules. Activation or inhibition of enzyme activity are associated with a
change in its spatial structure. The specificity of enzymes is one of the main
conditions for the ordering of the chemical reactions in the body. Apoenzyme,
coenzyme individually have low catalytic activity. With their connection to the
molecule holoenzyme ability to accelerate the reaction increases.
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