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
A uniflagellar sperm cell that is motile is referred to as a spermatozoon, whereas a non-motile sperm cell is referred to as a spermatium. Sperm cells cannot divide and have a limited life span, but after fusion with egg cells during fertilization, a new organism begins developing, starting as a totipotent zygote. The human sperm cell is haploid, so that its 23 chromosomes can join the 23 chromosomes of the female egg to form a diploid cell. In mammals, sperm develops in the testicles and is released from the penis. It is also possible to extract sperm through TESE.