. South African botany. Botany. 26 SOUTH AFRICAN BOTANY lignified tube with specially thickened end wall. These end walls are perforated with numerous holes, and through them the contents of one cell communicates with the contents of the next. This structure resembles A B. Pig. 15.—Sieve Tubes. A and B. Longitudinal section. C. Surface view of sieve plate, c. Companion cell. ca. Plate of callus, Sieve plate. a sieve, hence the name of these vessels. After a while the sieve plates become covered with a plate of callus. The sieve tubes contain a lining of protoplasm, but no nucleus. Accompa
. South African botany. Botany. 26 SOUTH AFRICAN BOTANY lignified tube with specially thickened end wall. These end walls are perforated with numerous holes, and through them the contents of one cell communicates with the contents of the next. This structure resembles A B. Pig. 15.—Sieve Tubes. A and B. Longitudinal section. C. Surface view of sieve plate, c. Companion cell. ca. Plate of callus, Sieve plate. a sieve, hence the name of these vessels. After a while the sieve plates become covered with a plate of callus. The sieve tubes contain a lining of protoplasm, but no nucleus. Accompanying them is always found a small thin-walled Companion Cell, containing proto- plasm and a large nucleus. Lastly, in many plants we find another kind of tube usually filled with a milky. 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 Storey, Francis W; Wright, K. London, New York, Longmans, Green
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Keywords: ., bookcentury1900, bookdecade1920, booksubjectbotany, bookyear1922
