| Abstrakt: |
ELECTRON microscope observations1–5on sections of chromosomes from various species reveal granules and threads of width ranging from about 20 to several hundred angstroms. Chromosomes disrupt on an air–water interface6into longer threads about 200–250 Å wide7–9. Our observations on sections of erythrocytes from chicken and lamprey reveal a regular structure within the condensed chromatin (heterochromatin) closely adjacent to the inner membrane of the nuclear envelope. To help in the elucidation of these structures, the sections were tilted in the electron microscope. The resulting data demonstrate, not unexpectedly, the importance of superposition effects in determining nuclear images. |
