Roles of Enzymes

The anabolic and catabolic processes in a cell are directed and regulated by enzymes. Without enzymes, these processes would be extremely sloe. Vital processes like cellular respiration, would not produce energy rapidly enough  to keep the cell alive.

    Enzymes speed up a metabolic reaction by lowering the amount of energy needed to start the reaction. They so arrange the reacting molecules in a manner that will cause the chemical change to take place rapidly.

   The types of enzymes present in a cell will determine the metabolic processes that will occur in it. This in turn will determine what the cell will be, a mesophyll cell in a green leaf manufacturing food by photosynthesis; a digestive cell in the gut wall of a hydra breaking down food; or a skin cell in our body producing the dark coloured pigment, melanin, in a given amount which will determine the colour of our skin. Our inherited traits, such ad skin colour, develop because the appropriate cells in our body have the relevant enzymes. The nucleus is the one that ensures that the  correct enzymes are present in these cells of an organism. So, an organism, whether unicellular or multicellular, is what it is because of its unique combination of enzymes.

Note : All living cells have the enzymes which dire t and regulate cellular respiration.