IGURE 11. Typical life cycles of dinoflagellates. Most dinoflagellates have haplontic life cycles. That is, the only diploid cell in the life history is the zygote which undergoes meiosis. Of those, many hologamous, the vegetative cell is also a functional gamete. A few go through a developmental stage in which gametes are formed from vegetative cells. Noctiluca (the lower life history) is diplontic in which the vegetative cell is diploid. During its gametogenesis, the products of meiosis divide many times and develop into isogametes, which are the only dinoflagellate-type cells in the life history. Image from Taylor (1987).