Brush Construction. 1  Selected hairs are separated into small piles. Each pile is combed to remove curled or cut hairs. 2  Hair piles are bundled, wrapped in newspaper and tied with string. The hair bundle is boiled in water to remove oils and straighten the hair. 3  A single brush can contain several different hair lengths.
1 The thyroid gland plays a primary role in your energy level, muscle growth, metabolic rate, and brain function. 2  Hypothyroidism is a common disorder in which the bodyâs ability to produce enough thyroid hormone is insufficient.hyroid Hormones. 1  The thyroid gland plays a primary role in your energy level, muscle growth, metabolic rate, and brain function. 2  Hypothyroidism is a common disorder in which the bodyâs ability to produce enough thyroid hormone is insufficient.
TSH causes the thyroid gland to make two hormones: triiodothyronine (T3) and thyroxine (T4). T3 and T4 help control your body's metabolism. Triiodothyronine (T3) and thyroxine (T4) are needed for normal growth of the brain, especially during the first 3 years of life. A baby whose thyroid gland does not make enough thyroid hormone (congenital hypothyroidism) may, in severe cases, be mentally retarded.