THE ROLE OF ENZYMESAre biological catalyst that regulate almost
all the cellular reactions.Speed up a specific biochemical
reactions in the cell.
Characteristics of enzymesSpeed up the rates of chemical
reactions but remain unchanged at the end of the reactions.Not
destroyed by the reactions.Have a specific sites called active
sites to bind to specific substrates enzymes are highly
specific.Needed in small quantities because they are not used up
but released at the end of a reaction.Reversible.The activity of
enzyme can be slowed down or stopped by inhibitors.Require helper
molecule, cofactors.
Naming of enzymesAccording to the name of the substrate by
adding aseEg; lactose lactase, sucrose sucrase, lipid lipase.Other
enzymes, pepsin, rennin, trypsin.
The sites of enzyme synthesisRibosome get information from
DNAThe different sequences of bases in DNA are codes to make
different proteins.mRNA is formed to translate the code into amino
acids,Amino acids bond together to form specific enzymes according
to the DNAs code.
Intracellular enzymesSynthesised and retained in the cell for
the use of the cell itself.Found in cytoplasm, nucleus,
mitochondria and chloroplast.
Extracellular enzymesSynthesised in cell but secreted to work
externally. Eg; digestive enzymes produced by the pancreas are
transported to the duodenum.Production of extracellular
enzymes:
