Abstract
Brief treatment of unfertilized starfish eggs with hypertonic sea water increases the rate of activation by subsequent exposure to butyric acid. This effect may be described as a sensitization to the activating influence of the acid. The curve representing the relation between the duration of the hypertonic treatment and the rate of acid-activation resembles the bimolecular reaction isotherm.In general the experimental facts of acid-activation (and of heat-activation) are consistent with the following simplified schema. Activation is the physiological result of the accumulation of a reaction product, called (provisionally) "the activating substance" (substance A) which is formed by the chemical union of two chief compounds. One of these, called (after the analogy with light-sensitization) the "sensitizing substance" (substance S), is already present in the egg; the other, the "acid-product" (substance B), is set free (e.g., by hydrolysis) under the influence of the activating acid. The equation S + B = A symbolizes this hypothetical activation-reaction.Treatment with hypertonic sea water increases the concentration of S at the site of the activation-reaction, through the abstraction of water and promotion of dehydrolytic synthesis. The resulting increase in the rate of acid-activation is thus explained. Treatment with dilute sea water should theoretically have the reverse effect, but in this case the experimental evidence is conflicting.The acid-product B appears to be formed at a rate proportional (through a certain range) to the concentration of acid; it is regarded as being set free by the hydrolysis of some normal egg-component at a rate controlled by the cH. The special hypothesis that the hydrolyzed compound is a phosphagen ester has, however, received no support from test experiments.The hypothesis that heat-activation is an effect of the formation of lactic acid by glycolysis is also not supported by experiments with iodoacetate and fluoride.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
