Ion Channels and the Cellular Behavior of Stylonychia
Unicellular organisms require some unique adaptations to their environment, such as the necessity to incorporate all functions needed for survival onto a single cell, and the ability to cope with their direct exposure to the outside world. Their unicellular existence imposes restrictions that multicellular organisms have circumvented by distributing different functions onto different cell types. This is most evident if we compare animal behavior with “cellular behavior” of protozoa. The sequence of events underlying behavior in animals includes sensory perception by sense organs, processing of the sensory information and translating this into motor programs by the nervous system, and movements carried out by activation of muscles. Thus, different types of cells and organs with varying degrees of specialization contribute to the behavioral performance of multicellular animals.
KeywordsDivalent Cation Outward Current Unicellular Organism Frog Skeletal Muscle Receptor Current
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