Asap explain why a key that fits into a lock is a useful model for the function of enzymes.

Keys(enzymes) are  specific to certain locks(substrate)

Explanation:

The key and lock model are used to illustrate the enzyme specificity to a substrate function. Enzymes are specific in the reactions they catalyze. An enzyme will only catalyze one specific reaction or a group of closely related reactions.

For enzymes to catalyze a reaction, the substrate(s) must fit in the active site on the surface of the enzyme. This forms an enzyme-substrate complex. The enzymes speed up the formation of the products. The products formed separate from the enzymes so that other substrate molecules can fit into the active sites.

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