Response in the Living and Non-Living

by Jagadis Chandra Bose

Fig. 30.—Curves Showing the Relation Between the Intensity of Stimulus and Response

Abscissæ indicate increasing intensity of stimulus. Ordinates indicate magnitude of response. (Waller.)

Fig. 31

Taps of increasing strength 1:2:3:4 producing increased response in leaf stalk of turnip.

I have obtained very interesting results, with reference to the relation between stimulus and response, when experimenting with plants. These results are suggestive of various types of response met with in animal tissues.

1. In order to obtain the simplest type of effects, not complicated by secondary phenomena, one has to choose specimens which exhibit little fatigue. Having procured these, I undertook two series of experiments. In the first (A) the stimulus was applied by means of the spring-tapper, and in the second (B) by torsional vibration.

(A) The first stimulus was given by a fall of the lever through h, the second through 2 h, and so on. The response-curves clearly show increasing effect with increased stimulus ([fig. 31]).