Chapter VII 



— 57 — 



The Chondriome 



acids (method of Benda and Meves) or with a mixture of formol 

 and potassium bichromate (method of Regaud), and then in fol- 

 lowing the fixation with a more or less prolonged treatment of a 

 3% solution of potassium bichromate, an operation called post- 

 chromatization which renders the chondriosomal lipides insoluble. 

 Once fixed, the chondriosomes stain clearly with iron haematoxylin, 

 acid fuchsin and crystal violet. They appear in the homogeneous, 

 barely-stained cytoplasm as intensely stained elements, with a very 

 clear outline and they very much resemble bacteria. It has been 

 shown that chondriosomes are made up of a lipoprotein complex 

 and that their affinity for stains is due to the lipides which they 

 enclose. Fixatives containing alcohol or acetic acid destroy these 

 lipides and the chondriosomes lose their chromaticity. 



In young cells, mitochondria generally predominate among the 

 chondriosomes. At a later stage they elongate into chondrioconts 

 which is the most usual form found in mature cells. The chondrio- 

 somes are permanent formations and 

 many cytologists consider that they are 

 incapable of forming de novo and increase 

 in number only by division of pre-existing 

 chondriosomes. At first the chondrio- 

 somes were regarded as organelles in 

 whose interior were formed most of the 

 products elaborated in the cell (fat, zymo- 

 gen, pigments) and whose role was the 

 same as that of the plastids in chlorophyll- 

 bearing plants. But observation of living 



material using tissue-culture technique .. 



does not confirm this idea. The very accurate observations of Noel 

 on the liver of rats are the only ones made so far which seem favor- 

 able to this belief. Noel has shown that when an exclusively nitro- 

 genous diet is given the rats, the chondriosomes of their liver cells, 

 which are normally in the state of chondrioconts, become large, 

 round bodies filled with protein. It seems, therefore, that the 

 chondriosomes accumulate protein and act as proteoplasts. The 

 phenomenon is reversible and, if the nitrogenous food is sup- 

 pressed, the proteoplasts lose their protein and resume the form 

 of chondrioconts. The role of the chondriosomes is still very ob- 

 scure in spite of this single observation. 



The chondriome In plant cells:- Chondriosomes in plant cells 

 were discovered even as early as 1904 by Meves who found them 

 in the nurse cells of pollen of the Nymphaeaceae. His results were 

 subsequently confirmed in various organs of the phanerogams by 

 the research of a certain number of investigators (Smirnow, 

 NicoLOSi-RoNCATi, Bonaventura) , among whom Duesberg and 

 Hoven will be given a special place, for in 1910 they produced ex- 

 cellent figures of the chondriome in embryonic cells of the pea and 

 bean. 



Fig. 21. — The chondriome. 

 A, frog's liver. B, salamander's 

 liver. C, frog's kidney. Re- 

 gaud's method. 



