The neural plate is one of the features exclusive to the embryonic development of chordates. It is located dorsally to the notochord. The neural plate is the rudimentary nervous system of the embryo. During early development ,the neural plate is formed from the ectodermal layer . It undergoes changes in the position and arrangement of it's cells to form the brain and the spinal cord which comprises the central nervous system. It forms tissues and eventually organs by the deepening of the groove which forms ridges which eventually folds and fuses to form the neural tube . The tube differentiates into the prosencephalon, the mesencephalon and the rhombencephalon, from which the organs are formed
"Haploid" refers to any cell that has 23 chromosomes (half of the total 46). "Gametes" are specifically sex cells that have 23 chromosomes. "Diploid" refers to any cell that has all 46 chromosomes. "Zygote" is the result of two gamete (haploid) cells fusing, and becoming a diploid cell.
