The primary function of the thyroid is the production of the iodine-containing thyroid hormones, triiodothyronine (T3) and thyroxine (T4) and the peptide hormone calcitonin. 1  T3 is so named because it contains three atoms of iodine per molecule and T4 contains four atoms of iodine per molecule.
Explorations of Africa. In the official role of a medical missionary, he set forth to Africa, arriving in Cape Town, South Africa in March of 1841. A few years later, he married Mary Moffat; the couple would have several children.
With his three ships, Eagles, Thienhoven and the African Galley, the Dutch Admiral, Jacob Roggeveen (1659 - 1729), went in search of the Southern Continent in August 1721. Until his southerly travels were prevented by ice floes, he managed to make the latitude of 60o.