. Animal hormones; a comparative survey. Hormones. 202 METABOLIC HORMONES hormone of the eyestalk (§ ); but this is not shown quantita- tively. Excessive water uptake cannot afford an explanation for the contrary findings in Hemigrapsus, where there is no weight in- 800 600 - .o 400 - 200. 30 40 50 60 Carapace breodth 70 Fig. 5-11. Relation of the total nitrogen content of the crab, Erio- cheir sinensis, to its size before and after moulting. The recorded values fall into three categories, (i) Total nitrogen in body (ordin- ates) measured before moulting and plotted against carapace bread
. Animal hormones; a comparative survey. Hormones. 202 METABOLIC HORMONES hormone of the eyestalk (§ ); but this is not shown quantita- tively. Excessive water uptake cannot afford an explanation for the contrary findings in Hemigrapsus, where there is no weight in- 800 600 - .o 400 - 200. 30 40 50 60 Carapace breodth 70 Fig. 5-11. Relation of the total nitrogen content of the crab, Erio- cheir sinensis, to its size before and after moulting. The recorded values fall into three categories, (i) Total nitrogen in body (ordin- ates) measured before moulting and plotted against carapace breadth (abscissae): % for non-moulting control crabs, (ii) Total nitrogen in body plus that in cast skin measured immediately after moulting and plotted against carapace breadth of old shell: O for control crabs moulting naturally; Q for eyestalkless crabs after forced moult, (iii) Same total nitrogen as in (ii) plotted against carapace breadth of neiv shell: © for controls that still fall within normal range shown by curves; B foi* eyestalkless crabs after forced moult due to loss of moult-inhibiting hormone, MIH. These show markedly low ratios and it is assumed that though loss of MIH does not affect nitrogen metabolism (ii), the loss of the DIURETIC HORMONE in the eyestalk allows increased water imbi- bition and swelling that increases the crab's size relative to its nitrogen content (from Koch, 1952). crease (Table 23). Whether the abnormally large volume increase observed during the first moult, following eyestalk removal in Eriocheir, might be followed later by a correlated increase in tissue synthesis remains to be investigated. Recent evidence on moulting hormones makes a tentative interpretation of these events possible,. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Jenkin, Penelope M. Oxford, New
Size: 1520px × 1644px
Photo credit: © Library Book Collection / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookcollectionbiodiversity, booksubjecthormones
