Electrical Activity associated with Ciliary Reversal in an Echinoderm Larva

摘要: ECHINODERM larvae are capable of a variety complex and apparently coordinated activities involving not only muscular movements but changes in the direction ciliary beating1,2. The eight-armed pluteus larva Strongylocentrotus droebachiensis (Cl. Echinoidea) normally swims with arms leading, when placed sea water containing abundant particulate matter, such as unicellular algae, it shows occasional irregular periods reverse locomotion. These caused by reversal beat ciliated bands which run around edges arms. At same time, material may be ejected from oral region, an activity assisted contraction anterior dilator muscles. During cilia epaulettes (isolated patches epithelium) or stop beating. response can evoked tactile electrical stimulation any part surface.