Cell nucleus
The nucleus is the largest cellular organelle in animal cells.
In mammalian cells, the average diameter of the nucleus is approximately 6 micrometres (µm), which occupies about 10% of the total cell volume. The viscous liquid within it is called nucleoplasm (or karyolymph), and is similar in composition to the cytosol found outside the nucleus. It appears as a dense, roughly spherical or irregular organelle. The composition by dry weight of the nucleus is approximately: DNA 9%, RNA 1%, Histone Protein 11%, Residual Protein 14%, Acidic Proteins 65%.
Nuclear transfer
Somatic Cell Nuclear Transfer (SCNT) is the process by which the nucleus of an oocyte (egg cell) is removed and is replaced with the nucleus of a somatic (body) cell (examples include skin, heart, or nerve cell). The two entities fuse to become one and factors in the oocyte cause the somatic nucleus to reprogram to a pluripotent state. The cell contains genetic information identical to the donated somatic cell. After stimulating this cell to begin dividing, in the proper conditions an embryo will develop. Stem cells can be extracted 5–6 days later and used for research.