title: Ultrastructural evidence of polarized synapses in the nerve net of Hydra.
mesh_terms: D006829:Hydra; D007395:Interneurons; D008854:Microscopy, Electron; D008870:Microtubules; D008928:Mitochondria; D009210:Myofibrils; D009415:Nerve Net / Q000166:cytology; D009420:Nervous System / Q000166:cytology*; D009469:Neuromuscular Junction / Q000166:cytology; D009474:Neurons; D013569:Synapses; D013570:Synaptic Membranes; D013572:Synaptic Vesicles