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.
David Livingstone was born on March 19, 1813, in Blantyre, South Lanarkshire, Scotland, and grew up with several siblings in a single tenement room.
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.