Sunday, November 23, 2008

Enzymes the "lock and key hypothesis"

1st I wanted to congratulate Malaysia Biology reference book (most of it) and text book for being so outdated...

1st what you know about enzyme?
you would have say like this : " enzymes are made up of proteins( tertiary structure) and are biomolecules that increase the rate of biochemical."
yes you are right...

but when i ask this question to my friends mostly their answer are perfectly wrong....=.="
here are my question
In the lock and key hypothesis model enzymes are key or lock and the substrate are lock or the key?
well their answer is enzymes are lock and the substrate is key....well that is totally wrong...
not their answers only but most of the Biology reference book and text book(malaysia) like Total Pro(Puan khoo use one), Sasbadi, Pelangi, and many many more...except for longman they do not say that enzyme are key or lock.

well let me prove that enzyme are not the lock.
first let us look at the general chracteristic of enzymes
thier chracteristic are:
1.they are very specific
2.are not use up/destroyed in the reaction
3.enzyme catalyse reversible reactions
4.many enzyme are only able to work under the presence of a coenzyme
5.they are sensitive to pH.

take a look on the general characteristic No.2 it says that enzymes are not use up or destroyed in the reaction, if all the conditions are normal to the enzymes.

ok look back to the lock and key model.
enzyme are lock. lock changes its shape when it is opened by a key right?
so we can't say that enzymes are lock because it DOES NOT SUIT ITS GENERAL CHRACTERISTIC.

and this lock and key model has proven inaccurate and the induced fit model is the most currently accepted enzyme-subtrate complex figure only.

so the conclusion is enzymes is key, substrate is the lock.

but 1 book i found that contains the correct answer , SAP
it stated that enzymes are key while the substrate are lock. thats right.

so why malaysia government don't want change the fact of this? do they do not know they are "planting" the wrong information/ideas/concept to the students?
hope that 1 day malaysia government will know that but i don't know when they are going to know it....

3 comments:

Daniel Ting said...

malaysian text book wrong?
normal lah.

Lee said...

ya la i dono why ar like that the intro for the person behind of the text book say that person wa...dono almost god like..but the information wrong=.=

xlnyeong said...

wow....your thinking is very profound...I just slogged on and never thought much.