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.
Dutch explorer Abel Tasman, in 1642, was the first non-Polynesian to sight the North West coast of the South Island of New Zealand.(There is a claim, disputed by most historians, that a Portuguese expedition led by Cristovao de MendonÃ§a beat him to it over a hundred years before in 1521-1524).