Sensitivity of regenerating limbs of an aquatic crustacean to variations in the concentration of hydrogen and phosphate ions in the external medium
✍ Scribed by Needham, A. E.
- Publisher
- John Wiley and Sons
- Year
- 1947
- Tongue
- English
- Weight
- 691 KB
- Volume
- 106
- Category
- Article
- ISSN
- 0022-104X
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✦ Synopsis
There is much evidence, chiefly of a qualitative nature, that the rate of regeneration, ancl the form of the regenerate, in aquatic animals are sensitive to reagents merely added to the surrounding medium (Korschelt, '27, p. 627, Hammett and Smith, '30). Morgulis and Green ( '31) were unable to confirm results obtained in this way by Hammett and Smith( 1.c.) while Paulain ( '38, p. 352) doubts whether in general, regeneration map be affected by this method of applying reagents. Recent research has continued to reveal such effects however (cf. Hainmett et al., '40 and earlier papers). I n the present paper an attempt has been made to elucidate the general problem aid to obtain a quantitative estimate of the sensitivity of the segenerating thoracic linibs of Asellus aquaticus ( L ) to variations in concentration of simple "physiological " ions, H and PO,, in the esternal mediuiii. llIETHOD Acids and alkalis, in lion-toxic concentration, were comparatively rapidly neutralized in the tap water medium used and buffers were necessary to maintain a reasonably constant pH value. The simple "physiological" buffers, mono-and dihydrogen phosphates of Na, were chosen. It was possible to test the 181