Gastrointestinal: Adjective referring collectively to the stomach and small and large intestines. The commonly used abbreviation for gastrointestinal is GI. (Outside of medicine, GI can also stand for galvanized iron, general issue or government issue-as in GI Joe).
Before the extracellular matrix is calcified, the tissue is called osteoid (bone-like) tissue. When the concentrations of calcium and phosphate ions rise high enough, they are deposited into the extracellular matrix, and the bone calcifies.
The adenoid, unlike the palatine tonsils, has pseudostratified epithelium. The adenoid is often removed along with the palatine tonsils. Development. Adenoids develop from a subepithelial infiltration of lymphocytes after the 16th week of embryonic life. They are part of the so-called Waldeyer ring of lymphoid tissue which includes the palatine tonsils and the lingual tonsils.