The effects of mechanical shock on locomotion in Amoeba proteus

✍ Scribed by Harry T. Folger

• Publisher: John Wiley and Sons
• Year: 1926
• Tongue: English
• Weight: 634 KB
• Volume: 42
• Category: Article
• ISSN: 0362-2525
• DOI: 10.1002/jmor.1050420202

✦ Synopsis

Abstract

Amoeba responds to a mechanical shock by a cessation of movement which occurs shortly after the application of the stimulus. The length of the reaction time, the period intervening between application of stimulus and the response, varies inversely with the magnitude of the shock. After stopping Amoeba remains quiescent for a short time, and the length of this period of quiescence varies directly with the magnitude of the shock. A certain amount of time must elapse after a reaction before another can be obtained; during this time the animal reverts to the physiological state which existed prior to the first shock.

Partial recovery from the effects of a shock is manifested by a reaction time that is longer than after complete recovery, and a period of quiescence which is shorter. A shock which in itself is too slight to cause a cessation of movement may result in the lack of a response to a heavier one which follows immediately after it, although under other conditions the second shock would have called forth a reaction. If the second shock, however, is made sufficiently heavy, it will bring about a response, despite the effects of the first. This is what would be expected if the reactions take place in accordance with the Weber‐Foechner law.