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.
When Scottish pioneer David Livingstone first laid eyes on Victoria Falls straddling Zimbabwe and Zambia, he wrote that upon such an awe-inspiring sight, âangels in their flight must have gazed.â More debatable is the best time to visit the falls.