.
No idea.
It is something very specific and requires specific knowledge that no one of our tutors possess, unfortunately.
This site is to help school students in Math and in Algebra.
For this question find another, more appropriate site.
Happy learning !!
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Nevertheless, I put this string into GOOGLE search
"The line graph shown here represents the reaction rate of an enzyme-assisted reaction in the body at various temperatures"
and it gave me some pdf-file titled Enzimes1.pdf.
Surely, I downloaded it in my computer and read it.
On pages 4 and 5 (4 of 12 and 5 of 12) the document shows exactly your plot, your question and explanations.
Unfortunately, I was not able to extract the link.
but it was THE SECOND REFERENCE in that GOOGLE list.
Also try this keyword in GOOGLE search: "Lab #4: Enzymes - ResearchGate"
Try, and if the fortune will be on your side, you may get this document.
In case you complete it successfully, do not forget to send your "GREAT THANKS" to me, because I found the source for you.
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Couple of days passed after my response to you, and I didn't get any feedback from you . . .
Therefore, it is just clear for me your relation to your own post and to the content of this issue.
But it is not so and not the same for me . . .
Therefore, I simply copied and pasted here this part from that document:
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Temperature is the average kinetic energy of a
system. Kinetic energy, in turn is the energy in
motion. This means that at higher temperatures
particles tend to be moving more quickly than
they are at slower temperatures. In solids,
molecules remain in roughly the same position
in space but vibrate more. In liquids and gases,
where particles are free to move from one
location to another, these particles tend to do so
at greater speeds (Fig 4.10). Since particles are
moving more quickly, they also tend to collide
with one another more frequently and with
greater energy. Therefore, the rates of chemical
reactions (both catalyzed and non-catalyzed)
tend to increase as temperature increases.
Hypothetically, this should be an indefinite
relationship, meaning that an increase in reaction
should accompany an increase in temperature
regardless of how high that temperature is.
Many enzymes show an unusual relationship
between reaction rate and temperature (Fig
4.11). Although over much of the range of
temperatures biological organisms experience
there is an increase in enzyme activity with
increased temperature there is often a decrease
in reaction rates at very high temperatures (e.g.,
above 70 °C). Why does this occur? There
could be a number of reasons. For example, the
increase in temperature may weaken and
destabilize the bonds that link enzymes with
necessary cofactors, thus the rate of spontaneous
deactivation of enzymes increases. However,
perhaps the most important factor to consider is
that the shape of the enzyme can be influenced
by temperature. The secondary, tertiary, and
quaternary structures of proteins all rely on
relatively weak non-covalent bonds (e.g.,
hydrogen bonds, van der Waals forces, and ionic
bonds) to link different regions of the protein
together. Increasing temperature causes
increased random movement in different regions
of the protein, thus destabilizing these weak
bonds (Fig 4.12) and causing a change in the
shape of the protein (denaturization). If enough
of these weak bonds are broken, the shape of the
active site will begin to distort, and the enzyme
will lose its ability to bind substrate and catalyze
the reaction. Thus the decrease in reaction rate
is due to the inability of the enzyme to function
as a catalyst when it is denatured by heat.