Alters metabolic activities of many tissues and organs simultaneously
Paracrine Communication
Most common form of intercellular communication
Endocrine cells release chemicals (hormones) into bloodstream
Occurs between two cells of same type
Exchange of ions and molecules between adjacent cells across gap junctions
Limited to a very specific area
Occurs across synaptic clefts
Uses chemical signals to transfer information from cell to cell within single tissue
Highly specialized and relatively rare
Chemical message is “neurotransmitter”
Direct Communication
Ideal for crisis management
Endocrine Communication
