the anatomy of a hydra

abdomen adults anatomy animal biology body bones cavity cells cilia classification cnidarians cut eggs excretion feet food freshwater gillies head hermaphrodites histology hydras invertebrates larvae limbs lower micrographs morphology mouth mouthparts nature networks neural neurotoxins oral parasitism photoreceptors physiology pupae regeneration respiration sensory sprites stem structure symbiosis synapses system tentacles upper wings zoology