The scientific investigation is the systematic approach of the scientists to answer the questions about the world. It is applied almost all of the theories including the Theory of Natural Selection. Darwin's theory of evolution is a result of scientific investigation. In this theory, they investigate by observing the distribution of species.
Hormone – biologically active molecule that is released into circulation from site of synthesis and acts at a distant sitecan be either hydrophilic (polypeptide hormone) or lipophilic (steroid) – biogenic amines can be eitherbinds specific receptor – on cell surface (hydrophilic hormones) or inside cell (lipophilic hormones)lipophilic hormones bind carrier proteins to travel in circulation; hydrophilic hormones travel freelycis-acting elements – DNA segments in the promoter region which bind trans-acting elementstrans-acting elements – molecules that impact downstream gene transcription when they bind cis-acting elements
