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.
The king accepted the plan, and on September 20, 1519, Magellan set sail from Spain in command of five ships and 270 men. Magellan sailed to West Africa and then to Brazil, where he searched the South American coast for a strait that would take him to the Pacific. He searched the Rio de la Plata, a large estuary south of Brazil, for a way through; failing, he continued south along the coast of Patagonia.