Fertilised egg cell dividing, illustration. It has divided into two cells (blastomeres). After fertilisation the nuclei of the sperm cell and the ovum fuse to form a zygote. The zygote then undergoes repeated mitosis (cell division). Cell division occurs approximately every twenty hours, to form a cluster of cells known as a morula, which continues to divide to form a blastocyst, and subsequently the embryo. | |
Lizenzart: | Lizenzpflichtig |
Credit: | Science Photo Library / SUSAN LOCKHART |
Bildgröße: | 4562 px × 3211 px |
Modell-Rechte: | nicht erforderlich |
Eigentums-Rechte: | nicht erforderlich |
Restrictions: | - |