Carboxyl groups have an electronegative oxygen atom double bonded to a carbon atom. This carbon-oxygen bond is very polar and the fact that its a double bond increases the polarity of the bond.
PEA agar, also referred to as Phenylethyl Alcohol Agar is a medium  used by microbiologists to grow microorganisms. The ingredient that  supplies nitrogen is casein. Making the world better, one answer at a time.
There are three categories of peas: the English or shelling pea, the Chinese pea or snow pea and the snap pea. The differences between the last two, edible pod types, is in the maturity of the pea inside the pod.