A system of human anatomy, general and special . TRANSFORMATION OF ANIMAL CELLS. 1. Cells increase in size and change their shape. The cut () gives a good idea of the bizarre and erratic forms which cellsoccasionally assume. 2. Cells undergo an alteration Fig. their substance and the cell-walls may acquirethickness, or the whole cell mayflatten and its parietes coalesce,and thus a simple flat disk be theresult. A cell may also changeits chemical character, an in-stance of which is afforded by A-sthe cells of the cuticle, which,once soluble in acetic acid, be-come insol
A system of human anatomy, general and special . TRANSFORMATION OF ANIMAL CELLS. 1. Cells increase in size and change their shape. The cut () gives a good idea of the bizarre and erratic forms which cellsoccasionally assume. 2. Cells undergo an alteration Fig. their substance and the cell-walls may acquirethickness, or the whole cell mayflatten and its parietes coalesce,and thus a simple flat disk be theresult. A cell may also changeits chemical character, an in-stance of which is afforded by A-sthe cells of the cuticle, which,once soluble in acetic acid, be-come insoluble in the same after acquiring their corneous character. New deposits may also, as has before been stated, occur within thecell, so as almost to obliterate its cavity. 3. Division into fibrils. This occurs in the formation of feathersin birds. A cell elongates and becomes filled with fibres, which onthe sloughing away of the cell-wall remain and form the structureof the 44 OSTEOLOGY. 4. They change their relations to each 12. There is an exception to this, however, in the cells of the blood or blood-globules, which alwaysremain isolated. a. They may be united by an intervening sub-stance, the remains of the blastema, which maythus form a lamina, as cuticle. b. They may blend their parietes, as in thecase of cartilage. c. They may coalesce at certain points, andtheir parietes disappearing at the place of con-tact, a tubular canal may be formed. In this waynew vessels are organized. This tubular canal becoming the seat of a new and peculiar deposit, a solid fibre results,thus muscles and nerves are formed. TRANSFORMATION OF THE BLASTEMA. It is supposed, in addition to the formation of tissues by cells, thatthe blastema may organize itself into fibres, &c, but it has been ob-served, that when such an occurrence takes place, nuclei are alwayspresent. Homogeneous films and fibres are thus formed. This can be readily understood when we refle
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Keywords: ., bookcentury1800, bookdecade1840, booksubjectanatomy, bookyear1847
