PLS HELP how does gene knockout work?

This method involves creating a DNA construct containing the desired mutation. For knockout purposes, this typically involves a drug resistance marker in place of the desired knockout gene. This method then relies on the cell's own repair mechanisms to recombine the DNA construct into the existing DNA.

enzyme active site and substrate specificity

enzymes bind with chemical reactants called substrates. there may be one or more substrates for each type of enzyme, depending on the particular chemical reaction. in some reactions, a single-reactant substrate is broken down into multiple products