Question

The iodine derivative of amino acid tyrosine brings about effects on target cells by

• A. Altering gene expression
• B. Activating secondary messengers
• C. Activating membrane-bound receptors
• D. More than one option is correct

Answer 1

Answer: (A)

Thyroxine is a lipid-soluble hormone, which diffuses into the cell, where it binds to intracellular receptors, migrate to the nucleus, and activate specific target sequences of DNA. Thyroxine is a hormone produced by the thyroid gland. Thyroxine is important in controlling both development and maturation. It also controls metabolism in adult organisms.