True regarding autonomic system is
Autonomic nervous system
-        The highest centre is the hypothalamus.
-        Conduction speed is slower in ANS compared to somatic nerves. ANS is non-myelinated. 
-        Preganglionic parasympathetic fibers are lengthier because parasympathetic ganglia lie closer to the organs.
-        Ratios of preganglionic to post ganglionic fibers are 1:20 to 1:100 in sympathetic system.