Hla or human leukcyte antigens
a. must be carefully matched to avoid transplantation rejection
b. develop in 7 to 10 days
c. are manufactured in the bone marrow
d. cause lysogenic viruses to revert back to lytic viruses

b.

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