[Proofs]

Date:
1977
Reference:
PP/CRI/H/6/2/1
Catalogue details

Licence: In copyright

Credit: [Proofs]. Source: Wellcome Collection.

    18/34
    Figure Legends Fig. 1 (A, B and C) : Examples of partially disintegrated isolated human metaphase chromosomes at different stages of disintegration, from an almost intact chromosome to an extended fiber. Characteristic of all of these structures is that they appear to be composed of a well-defined fiber of about 0.4 pm diameter, the unit fiber (light microscopy after Giemsa staining). Fig. 2 : An example of the image of the unit fiber photographed slightly above the focal plane showing the characteristic appear ance of doubleness due to a phase effect which suggests a tubular structure for the unit fiber (light microscopy after Giemsa staining). Fig. 3 (A,B,C and D) : Electron micrographs of cross-sections of 600 to 800 A thickness of the unit fiber which is suggested to be a supersolenoid. Samples were embedded in Vestopal and stained with uranyl acetate. The diameter of the spiralized thin fiber is about 300 A, which corresponds to the dimensions of the solenoid (3,4). The diameter of the larger thin-walled supersolenoid struc ture is about 4000 A (= 0.4 ¿im). Fig. 4 : Electron micrograph of a unit fiber spread on a grid and stained with uranyl acetate. The fiber is seen to be folded and could be a circular structure.