A normal adult thyroid gland weighs 10 to 20 g and receives blood from bilateral superior and inferior thyroid arteries and a small artery called the thyroid ima. The thyroid secretes two hormones. Thyroxine (T 4) makes about 90% of hormone production, and triiodothyronine (T 3) produces the other 10%.
Fast Growing Cold Hardy Tree. - Grows up to 5 ft per year! The Quaking Aspen is well known for thriving in cold climates and poor soil... but it's also a brightly colored tree with many desirable characteristics.
Aspen needs full sunlight to grow to its full potential and is an extremely fast-growing tree in the right conditions. When other trees have died out, aspen is able to grow quickly in the available sunlight. However, it will die back when other trees overshadow it.