Complex sentence: Eds Dunod Sciences, Paris based on relations between zygote and parents, including ovuliparity with external fertilisation; oviparity, with internal fertilisation, where the female lays zygotes as eggs with a large yolk; it occurs in all birds, most reptiles, and some fishes.
Split into simpler sentences: Eds Dunod Sciences, Paris based on relations between zygote and parents, including two nonviviparous modes: ovuliparity, with external fertilisation, and oviparity, with internal fertilisation. In the latter the female lays zygotes as eggs with a large yolk; this occurs in all birds, most reptiles, and some fishes.