The posterior or rear region of a single-celled organism's body.
From cyto- (Greek kytos, 'cell') + -pyge (Greek puge, 'rump' or 'posterior'). This term was developed by protozoologists studying the anatomy of microscopic organisms in the 19th century.
This word reveals how scientists anthropomorphize even single-celled creatures by giving their different regions human-like names—the 'rear end' of a paramecium is as important to its survival as yours is to you!
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