1 Cold sores later crust over with a scab and are usually associated with tingling, tenderness, or burning before the actual sores appear. 2  Mouth irritation. 3  The irritation can be caused by: 4  Biting your cheek, tongue, or lip. 5  Wearing braces or another type of dental apparatus, or having a sharp, broken tooth.
Main Image: The Pituitary gland is a pea-sized endocrine (hormone-producing) gland weighing about 0.5 g situated at the bottom of the skull sandwiched between the optic nerves, in humans. The pituitary gland secretes hormones. Hormones are chemicals that travel through the blood stream.
The pea-sized pituitary gland, located at the base of the brain below the hypothalamus, is considered the most crucial part of the endocrine system, producing growth hormone and hormones that control other endocrine glands. Specialized cells of the nervous system also produce hormones.