Electron microscopy of DNA molecules from blastoderm nuclei and yolk granules beneath blastoderm of fertilized and unincubated chicken eggs.

The DNA molecules isolated from the blastoderm nuclei and yolk granules beneath the blastoderm of fertilized and unincubated chicken eggs were observed under electron microscope, using the DNA sample of calf thymus as control. The results showed that both nuclear and yolk DNAs are linear, and their molecules are very similar to those of thymus DNA in shape. Since chromatin was first prepared from blastoderm nuclei and yolk granules respectively and then DNA was isolated from both of chromatin samples, it could be concluded that yolk granules possess both DNA chromatin as nuclei do.