Stuck on a problem? Get great tutoring at an affordable price with Chegg. Click here to join and get your 1st 30 minutes Free!

Hormones

From Biology-Online Dictionary
Jump to: navigation, search

Hormones

chemical substances having a specific regulatory effect on the activity of a certain organ or organs. The term was originally applied to substances secreted by various endocrine glands and transported in the bloodstream to the target organs. It is sometimes extended to include those substances that are not produced by the endocrine glands but that have similar effects.