Pan-African flag - History. 1  The flag was created in 1920 by members of UNIA in response to the enormously popular 1900 coon song Every Race Has a Flag but the Coon. [4] which has been cited as one of the three songs that firmly established the term coon in the American vocabulary.
Whether a hormone binds to a receptor inside or outside a cell depends on the chemical nature of the hormone and its compatibility with the cellâs fatty outer membrane. The membraneâs fat layers impede water-friendly hormones from passing through but allow fat-derived hormones to readily enter the cell.
The binding of neurotransmitters to receptors is often described using a lock and key metaphor. A âkey,â or neurotransmitter, neatly binds with a receptor âlockâ resulting in the propagation or dampening of the neural signal (also referred to as the action potential). Receptors, however, are not quite as specific as a single matching lock and key.