ISSN:
1573-0832
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Medicine
Notes:
Summary 1) Through out the comparison of dissociation in asporigenous yeasts with the phenomena related to the variability of fungi, may be concluded that the dissociation is one of the cases of the transitional variation of fungi (fluctuation non mutation), namely, progressive, reversible, of constant and uniform direction, with multiple and correlated variation. 2) The population of a cultural clone is apparently composed of a mosaic of individual with varied aptness, including the aptness to produce colonies of „R” and „S” type. A monogenetic colony may be considered as a Turesson's „ecospecies” including many „ecotypes”, and, with a few admissions, the dissociation may be explained at the light of cyclogenetic theory (as enunciated by Leonian for fungi). 3) Experiments performed using hypo-, iso- and hypertonic solutions of saccharose as „incitant” to the dissociation demonstrated the high dissociation of „RS” and „R” forms from „S” form (better using hyper- than hypotonic solutions) but not of „SR” or „S” forms from „R”, so that one of the outstanding factors on dissociation may be considered the cellular osmotic power of the yeast cells („eterosmotic” hypothese). 4) According to our point of view, the normal „S” clone composed of only „S” cells is incapable of dissociation; a clone composed of „S” cells with a few „R” cells is suitable to dissociate into „SR” and „R” types; a clone of „R” type composed of „R” and a few „S” cells is suitable to dissociate into „RS” and „S” types; a clone composed of only „R” cells is incapable of dissociation. 5) A non-finalistic correlation with osmophilic cells other than biochemical and pathogenetie activities is the greater cellular polymorphism (related with the type of colony).
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00450239
