. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 414 J. B. JENNINGS AND RAY GIBSON intestine and their secretions retain their spherical form for a time. Within twenty minutes of feeding, however, the spheres have dissolved and previously enzymically inert boiled food begins to show peripheral endopeptidase activity as proteolysis commences. Eventually the entire contents of the intestine show this reaction, and become progressively more homogeneous, but no other enzymes could be demonstrated. Thus it would appear that extracellular digestion is entirely proteolytic and du
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 414 J. B. JENNINGS AND RAY GIBSON intestine and their secretions retain their spherical form for a time. Within twenty minutes of feeding, however, the spheres have dissolved and previously enzymically inert boiled food begins to show peripheral endopeptidase activity as proteolysis commences. Eventually the entire contents of the intestine show this reaction, and become progressively more homogeneous, but no other enzymes could be demonstrated. Thus it would appear that extracellular digestion is entirely proteolytic and during this stage the pH of the gut contents is , as determined by application of indicators to samples withdrawn by means of a micro- pipette. The duration of extracellular proteolysis depends directly upon the size of the meal. Phagocytosis of food particles commences within thirty minutes of feeding, as soon as proteolysis in the gut lumen begins to break up the food, and this con- tinues until the columnar cells of the gastrodermis are loaded with food vacuoles. Material showing endopeptidase activity may still persist in the gut lumen at this stage if a large amount of food has been taken, but as intracellular digestion in the earlier food vacuoles is completed so new ones form distally in the columnar oe. uc. 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 Marine Biological Laboratory (Woods Hole, Mass. ); Marine Biological Laboratory (Woods Hole, Mass. ). Annual report 1907/08-1952; Lillie, Frank Rattray, 1870-1947; Moore, Carl Richard, 1892-; Redfield, Alfred Clarence, 1890-1983. Woods Hole, Mass. : Marine Biological Laboratory
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
