[candiishop]

Enzymes are catalysts because they:

a) Increase the rate of reaction
b) Increase the amount of product obtained in the reaction
c) Bind weakly to the products of the reaction
d) Bind tightly to the substrate of the reaction
e) Bind tightly to the transition state of the reaction

My answer is A but a friend thinks D?

Thanks.

[Yggdrasil]

I would agree with A because that is the definition of a catalyst and enzymes definitely do increase the rate of reactions.  D is not correct because binding tightly to the substrates is not a necessary feature of catalysts and not all enzymes bind very tightly to their substrates.

[Professor]

My answer is also (a). 

[english]

I would say A as well, because not only is this statement correct, but binding tightly doesn't even make any sense to be always the case.

I don't know much about enzymes (yet), but I do know that such a scheme cannot always involve "tight" bonding in order for the substrate to be catalyzed.  Hand in a glove type thing.


That's just my inutition at work. 

[profmsg]

i guess your answere is correct and follows the definition of calalyst.
the answere d is not correct because once the catalyst binds very tightly with substrate, they are not released from the substrate so no product is formed.