A cigoto is the initial cell formed when a sperm cell from a male fertilizes an egg cell from a female. This process marks the beginning of a new organism's development. The cigoto contains genetic material from both parents, which determines the traits of the future individual. After fertilization, the cigoto undergoes several divisions and transformations, eventually developing into an embryo. This stage is crucial for the formation of all the necessary structures and systems of the organism, leading to the eventual growth into a fully developed fetus during pregnancy.