EGL USA is one of the largest and oldest independent gemological institutions focusing on gemstone certification and research. Originally part of an international network founded in Europe in 1974, EGL USA opened its first U.S. lab in the heart of New York's international diamond and jewelry district in 1977.
the fusion of the nucleus of a haploid sperm cell and the nucleus of a haploid egg cell, forming a diploid zygote zygote diploid cell formed when the nucleus of a haploid sperm cell fuses with the nucleus of a haploid egg cell tetrad group of four chromatids formed during prophase I of meiosis by the two sister chromatids in each of the two homologous chromosomes
The process of development begins with the fusion of gametes : egg (ovum) and sperm. The motile sperm swims to the egg, pierces its cell membrane and enters the cell. Fertilization is the fusion of the nuclei of the egg and sperm, and the single cell that results from this fusion is called the fertilized egg or zygote (see Figure 2). During fertilization, the genetic material of the sperm and egg are combined.