- Target cells: Located in distant parts of the body.

- Transport: Requires the circulatory system (blood) to reach target cells.

- Effect: Can have widespread effects on various organs and tissues simultaneously.

Paracrines:

- Target cells: Cells in the immediate vicinity (nearby cells) of the releasing cell.

- Transport: Diffusion through the extracellular fluid.

- Effect: Act on neighboring cells without entering the bloodstream.

Autocrines:

- Target cells: The releasing cells themselves.

- Transport: Released directly into the extracellular space and bind to receptors on the same cell.

- Effect: Regulate their own activities or functions in an autocrine manner.