| Abstrakt: |
Discs cut from plant storage organs have long been favourite material for experiments upon salt absorption. A recent series of papers (Steward, 1932 a–c, 1933 ; Steward, Wright and Berry, 1932) which refers especially to potato tissue indicates that in the past the attention directed to the respiration of these tissues was far too scanty. With the development of an adequate technique (Steward, 1932 b) the general principles operating in the case of potato tissue became increasingly apparent, and the occasion thus arose to extend the investigations to other storage organs. A survey of several storage organs (Berry and Steward, 1934) revealed that discs cut from artichoke tubers combined a conspicuous ability to absorb the salt studied (KBr) with a characteristic respiratory behaviour which presented features somewhat different from those of potato. The present paper records an attempt to ascertain whether the observed behaviour in respiration is reflected in salt absorption in the manner anticipated and to determine further details of the absorption process, with particular reference to potassium bromide and artichoke tissue. A matter which received some special attention was to ascertain whether the absorbed salt replaces ions already within the cell, or accumulates, against a concentration gradient, in the vacuole where it exists in true solution without displacing other ions. Since they were obtained, the results here presented have gained added interest in the light of the results published by Briggs and Petrie (1931) and, more particularly, in view of a theoretical interpretation of absorption by cells (Briggs, 1932) based upon ionic exchange. |
