The Encyclopaedia Britannica; .. A dictionary of arts, sciences and general literature . e protoplasm may be-come a sac containing cell-sap;and if growth of the cell-wall con-tinues the protoplasm eventuallyforms a mere Uning of the cell-wall constituting the primordialutricle of Von Mohl. The proto-plasm in some cells exhibits pheno-mena of movement within the cell-wall of a definite character. Thusin the internodal cells of Charace®(fig. 7) a movement of protoplasmround the longest diameter of the cellis seen, and in the hairs of Trades-cantia (Virginian Spiderwort) a cir-culation of protopl
The Encyclopaedia Britannica; .. A dictionary of arts, sciences and general literature . e protoplasm may be-come a sac containing cell-sap;and if growth of the cell-wall con-tinues the protoplasm eventuallyforms a mere Uning of the cell-wall constituting the primordialutricle of Von Mohl. The proto-plasm in some cells exhibits pheno-mena of movement within the cell-wall of a definite character. Thusin the internodal cells of Charace®(fig. 7) a movement of protoplasmround the longest diameter of the cellis seen, and in the hairs of Trades-cantia (Virginian Spiderwort) a cir-culation of protoplasm occurs. Theseconstitute the phenomena of rotationand circulation. The nucleus (fig. 1, i) is present inthe cells of all the higher plants. Itis a small rounded differentiated por- ^tion of the protoplasm, and frequentlycontains vacuoles, which are termednucleoli (fig. 1, kk). It may be in thecentre of the cell or close to thesides, but it may change its of the protoplasm are also differentiated as grainsor granules, to which colouring matters are attached ; but. Fig 7. small portion of a Chartmagnified to show the intra-celliUar ciiculation. Theanows mark the directionof the course of the proto-plasm in the cells. The clearspaces are parts where ther«is no movement VARIETIES OF TISSUE.] BOTANY 85 these wiil bo noticed hereafter. Tlie protoplasn; in oldcells may disappear, and then all growth ceases, and the cellsconsist of a mere framework; or it may remain, and thengrowth of the cell continues. And it is by a re-arrangementof the molecules of this protoplasm that the formation ofnew cells begins,—the nucleus entering also into the pro-cess. By the term cell-sap is meant the fluid contained inthe vacuoli. It consists in great part of water, in whichare dissolved various salts, derived from without, andcompounds formed by assimilation in the plant the latter we may mention inulin, a substanceclosely allied to starch and sugar, found in Co
Size: 1046px × 2388px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1900, booksubjectencyclo, bookyear1902
