The hypothalamicâpituitaryâthyroid axis (HPT axis for short, aka thyroid homeostasis or thyrotropic feedback control) is part of the neuroendocrine system responsible for the regulation of metabolism. As its name suggests, it depends upon the hypothalamus, the pituitary gland, and the thyroid gland.The hypothalamus senses low circulating levels of thyroid hormone (Triiodothyronine (T3) and Thyroxine (T4)) and responds by releasing thyrotropin-releasing hormone (TRH).he TRH stimulates the pituitary to produce thyroid-stimulating hormone (TSH). The TSH, in turn, stimulates the thyroid to produce thyroid hormone until levels in the blood return to normal.
Average Shipping weight of Media. Average weight of a: DVD weighs an average of 4 oz. Xbox 360 video game or a PS3 Game (COMPLETE) weighs an average of 5 oz. Same for a Wii Game. A complete CD weighs an average of 4 oz. Variables: A 2 Disc DVD set, weighs an average of 5 oz . If either of these items has a Cardboard Sleeve, add 1 oz to the weight. *Most of these items actually weigh less that 4.5 oz. but you have to round up if it exceeds an ounce, for shipping purposes. I will do a post for books next.
The deluxe version. Slim DVD case with printed insert. This case will hold 2 DVDs, but only one is included here. Total cost for DVD case, envelope & postage: $3.12 to $3.35. Postage is $2.74 of that. Weight is 3.5 oz. The heavy weight matte photo paper used for the insert would add another 22 cents. The blank DVD will run you another 22 to 40 cents in both cases. * Note that if the DVD is considered Rigid, it will add 22 cents to the postage.