BSIP, ESTIOT / SCIENCE PHOTO LIBRARY BSIP, ESTIOT / SCIENCE PHOTO LIBRARY
Fertilisation. Computer artwork of a human sperm or spermatozoon (red) successfully fertilising an ovum (green). The sperm has penetrated the thick protein coat of the ovum by releasing enzymes. The head of the sperm is inside the ovum and will release its genetic material. Once this has happened, the ovum becomes impermeable to other sperm. Fertilisation is the fusing of the male (sperm) and female (ovum) sex cells to form a zygote. This will contain genetic material from both sex cells, and the new individual that may develop will inherit characteristics from both parents.
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