The enzyme found in target tissues of the thyroid hormones that converts thyroxine (also known as tetraiodothyronine or T4) to triiodothyronine (T3).
Specifically, 5'-deiodinase converts T4 to the active form of the thyroid hormone, T3.
5-Deiodinase converts T4 to the inactive form of the thyroid hormone, reverse T3 (rT3).
Depolarization
Definition:
Refers to a change in the value of the membrane potential, where the membrane potential becomes less negative (or more positive) than the resting membrane potential.
The first region (i.e., most proximal region) of the small intestine. Chyme leaving the stomach (through the pyloric valve) first enters the duodenum. The contents of the duodenum empty into the jejunum (middle region of the small intestine). In adult humans, the duodenum is about 25-38 cm (10-15 inches) long.