Here's a breakdown:
* "Trope" comes from the Greek word "trope," meaning "to turn" or "to change."
* "-in" is a common suffix used to indicate a substance, particularly a protein.
Therefore, "-tropin" suggests something that "turns" or "changes" a specific tissue or organ.
Examples:
* Corticotropin (ACTH): Stimulates the adrenal cortex to produce cortisol.
* Thyrotropin (TSH): Stimulates the thyroid gland to produce thyroid hormones.
* Somatotropin (Growth Hormone): Promotes growth and development.
Note: While "-tropin" is commonly associated with hormones, there are some exceptions where it might refer to other substances with similar stimulatory effects.