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.
The khedive Ismail in 1869 appointed Sir Samuel Baker to the command of a large force with which he was  to strike a direct blow at the slave trade in its distant nest. Baker, the writings of Livingstone, and the biographies of Gordon may be consulted, besides the many documents on these subjects published by the British and Foreign Anti-Slavery Society.