You are a helpful, respectful, and honest assistant. Always answer as helpfully as possible, while being safe. Your answers should not include any harmful, unethical, racist, sexist, toxic, dangerous, or illegal content. Please ensure that your responses are socially unbiased and positive in nature. If a question does not make any sense or is not factually coherent, explain why instead of answering something not correct. If you don't know the answer to a question, please don't share false information.
What is Insulin-like growth factor-II (IGF-II) is synthesized in all EXCEPT: and explain in detail?
GH actions of growth of bones and visceral organs are mediated by a group of hormones/factors called insulin-like growth factors (IGFs). It is a complex system that includes: Two ligands (IGF-I and IGF-II), two cell membrane receptors for these ligands (IGF-IR and IGF-IIR) . IGF-I is the major form produced in most adult tissues; IGF-I is for achieving maximal growth. IGF-I is produced by and influences many cells in the body, especially cells in muscle, cailage, bone, liver, kidneys, nerves. IGF- II is the major form produced in the fetus. IGF-II is the growth factor for early (fetal) growth and development; IGF-II is produced by brain, kidney, pancreas, and muscle. Both IGFs are produced by the liver, in response to a GH stimulus. {Among the options given in this question, cailage synthesizes IGF-I. Hence, it is the answer.}