Sulfa drugs like Bactrim, given for bacterial infections, inhibit bacteria by blocking folic acid synthesis. The precursor molecule of folic acid is para-amino benzoic acid (PABA). Interestingly, PABA has a structure very similar to a sulfa drug. If a sulfa drug is present, the bacterial enzyme will bind the sulfa drug because of structural similarity. This is an example of .

What is a difference between systemic and pulmonary circulation? a. systemic circulation carries oxygenated blood to the lungs and pulmonary circulation carries deoxygenated blood to the body. b. systemic circulation carries deoxygenated blood to the lungs and pulmonary circulation carries oxygenated blood to the body. c. systemic circulation carries deoxygenated blood to the body and pulmonary circulation carries oxygenated blood to the lungs. d. systemic circulation carries oxygenated blood to the body and pulmonary circulation carries deoxygenated blood to the lungs.