Iodine in biology ring iodine atom, and also convert T3 to 3,3'-Diiodothyronine (T2) by removing an inner ring atom. Both of the latter products are inactivated hormones which have essentially no biological effects and are quickly prepared for disposal. A family of non-selenium-dependent enzymes then further deiodinates the products of these reactions. Selenium also plays a very important role in the production of glutathione, the body's most powerful antioxidant. During the production of the thyroid hormones, hydrogen peroxide is produced in large quantities, and therefore high iodine in the absence of selenium can destroy the thyroid gland (often described as a sore throat
Suprapedal gland the suprapedal gland of the land snail "Pomatias elegans" there are three types of gland cells: cells producing mucoproteins, cells producing proteins and cells producing sulphated mucopolysaccharides. For example, the land slug "Leidyula floridana" has gland cells in the suprapedal gland which produce weakly acidic mucopolysaccharides, neutral mucopolysaccharides and a protein. Suprapedal gland The suprapedal gland or mucous pedal gland is an anatomical feature found in some snails and slugs. It is a gland located inside the front end of the foot of gastropods. The term "suprapedal" means "above the foot". The function of this gland is to produce mucus.