. Quain's elements of anatomy . f granules or globtdes,which subsequently become fused together end to end, and are not at anytime connected with cells (Fig. 73). To fonn an elastic membrane, in place ofbeing arranged in lines the globules are deposited in small patches, and by Fig. 73. — Development of Fig. 73. elastic tissue by deposi-tion op fine grandles(Ranvier). g, moniliform fibres formedof rows of elastin ■ granules;p, flat platelike expansion ofelastic substance formed by thefusion of elastin granules. their fusion the membraneis formed (p). In elasticcartilage the granules firstmake
. Quain's elements of anatomy . f granules or globtdes,which subsequently become fused together end to end, and are not at anytime connected with cells (Fig. 73). To fonn an elastic membrane, in place ofbeing arranged in lines the globules are deposited in small patches, and by Fig. 73. — Development of Fig. 73. elastic tissue by deposi-tion op fine grandles(Ranvier). g, moniliform fibres formedof rows of elastin ■ granules;p, flat platelike expansion ofelastic substance formed by thefusion of elastin granules. their fusion the membraneis formed (p). In elasticcartilage the granules firstmake their appearance, it istrue, in the immediate neigh-boui-hood of the cartilage-cells ; but although thisrenders it probable that the deposition of the granules is influenced by the cells, it does not provethat they are formed by a direct conversion of the cell-protoplasm. Indeed,the subsequent extension of the fibres into those parts of the matrix whichwere previously clear of them, and in which no such direct conversion of. 72 CONNECTIVE TISSUES. cell-protoplasm seems possible, is a strong argument in favour of the depositionhypothesis. The view which supposes that a direct conversion of the protoplasm of theconnective tissue cells takes place into fibres, both white and elastic, has of lateyears been widely adopted, but it seems to rest less upon observation than upon adesire to interpret the facts in accordance with the conceptions of Beale and , according to which every part of an organised body consists either ofprotoplasm (formative matter), or of material which has been protoplasm (formedmaterial), and the idea of a deposition or change occurring outside the cells in theintercellular substance is excluded. But it is not difficult to show that a f or-mationof fibres may occur in soft substances in the animal organism, independently of thedirect agency of cells, although the materials for such formation may be furnishedby cells. Thus in those coelenterate ani
Size: 1866px × 1339px
Photo credit: © Reading Room 2020 / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., boo, bookcentury1800, booksubjectanatomy, booksubjecthumananatomy
