Final answer:
The sympathetic nervous system can simultaneously activate multiple effector organs due to its divergent connections, enabling a coordinated response, and the adrenal medulla's release of epinephrine and norepinephrine into the bloodstream.
Step-by-step explanation:
The ability for the sympathetic nervous system to activate many effector organs simultaneously is mainly due to the sympathetic division of the autonomic nervous system being activated during stressful "fight or flight" situations. The connections in the sympathetic system diverge from a limited region of the central nervous system (CNS) to a broad array of ganglia, allowing multiple effector organs to be activated together in a coordinated systemic response. This divergence permits a single preganglionic neuron to have numerous targets, potentially ranging from 10-20, thereby amplifying the sympathetic response. Additionally, the adrenal medulla plays a key role as it releases epinephrine and norepinephrine into the bloodstream, spreading the sympathetic signal quickly throughout the body.