. Hydration and growth. Growth (Plants); Plants. 116 Hydration and Growth. tein, and salt mixture lies below 46° C. and is probably above 40° C, as both rate and total capacity become uncertain at 46° C. and above. The agar-oat protein mixture has a higher initial capacity at 46° to 47° C, but does not appear to absorb as much water as it did at Table 95. Swelling of agar. 4 hours. 8 hours. 10 hours. 12 hours. 16 hours. 20 hours. 24 hours. 18 to 21° C 27° C 875 806 944 1,000 1,056 1,292 1,472 1,750 1,611 1,306 1,333 961 889 1,083 1,083 1,167 1,389 1,556 1,778 1,667 1,389 1,417 1,069 1,000 1,13
. Hydration and growth. Growth (Plants); Plants. 116 Hydration and Growth. tein, and salt mixture lies below 46° C. and is probably above 40° C, as both rate and total capacity become uncertain at 46° C. and above. The agar-oat protein mixture has a higher initial capacity at 46° to 47° C, but does not appear to absorb as much water as it did at Table 95. Swelling of agar. 4 hours. 8 hours. 10 hours. 12 hours. 16 hours. 20 hours. 24 hours. 18 to 21° C 27° C 875 806 944 1,000 1,056 1,292 1,472 1,750 1,611 1,306 1,333 961 889 1,083 1,083 1,167 1,389 1,556 1,778 1,667 1,389 1,417 1,069 1,000 1,139 1,278 1,208 1,417 1,583 1,833 1,111 1,054 1,168 1,333 1,250 1,444 1,153 1,083 1,222 29 to 31° C 39 to 41° C 40 to 41° C 46 to 47° C 48 to 49° C 1,708 1,416 • Averages. 18 to 21° C 27° C 875 1,028 1,611 1,320 978 1,125 1,667 1,403 1,069 1,244 1,708 1,111 1,222 1,163 39 to 41° C 46 to 49° C 1,416 a temperature a few degrees lower. The probable error at the high- est temperatures is great, however, and conclusions as to a separation of initial rate and final capacity should be made with caution.^ The relation of temperature to swelUng of agar and of these colloidal mixtures is of interest because of the fact that they lie within the range of activities of plants. The greater number of seed-forming plants FiQ. 21.—Tracing of auxograpbic records showing swelling of plates of agar mm. in thickness at v£trious temperatures. The 5 mm. and 4-hour intervals of the record-slip are shown. Increase is denoted by the downward movement of the pen, which amplifies the actual increase 20 times. The initial and following rates are well illustrated. do not endure air-temperatures of above 45° or 46° C. The tempera- ture of the stems or growing-zones in such exposures can not be cal- culated from such data unless sunlight exposure is known. Actual temperatures of the tissues have been taken by a few observers, from 1 See Freundlich, H. K
Size: 3203px × 780px
Photo credit: © The Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1920, booksubjectplants, bookyear1920
