Here's a small picture I drew to demonstrate one of the abilities of a Noryoo.
A Noryoo has two glands located in its upper throat. One produces a strong acidic chemical, the other produces a strong alkaline chemical. If threatened, a Noryoo can shoot one of the chemicals from these glands to defend itself. Its mouth is resistant to them, so it isn't at risk of hurting itself. Noryoo have learned to only spray one chemical at a time, since mixing them causes the same kind of reaction as vinegar and baking soda.