Final answer:
Enzymes are catalysts that speed up chemical reactions by lowering the activation energy required. They are highly specific proteins that bind to substrates, facilitating reactions without being consumed.
Step-by-step explanation:
Enzymes are protein molecules that act as catalysts to speed up chemical reactions.
These biological catalysts are crucial for facilitating the myriad of reactions necessary for life by significantly lowering the amount of activation energy required for reactions to occur.
An enzyme operates by binding to its specific substrates and holding them in an optimal orientation, thereby enhancing the bond-breaking and bond-forming processes. Importantly, enzymes do not get consumed in the reaction, allowing them to be reused.
One key characteristic of enzymes is their specificity; they are structured with unique active sites that match only particular substrates.
This interaction is sometimes described by the 'induced fit model', where the binding of the substrate induces a conformational change in the enzyme, optimizing its function. After the catalytic action, the products are released and the enzyme returns to its original shape, ready to catalyze another reaction.