Transcription: Fertilization is the key to the process of biological development. It occurs when the male sperm cell unites with the female ovum or egg. Hereditary material from two different parent cells combine to form a new individual, similar to the parents but completely unique. Hundreds of sperm cells approach a single egg. Only one of them attaches and a change immediately occurs in the membrane that keeps others from attaching. The sperm penetrates the membrane and egg activation occurs. The sperm head disengages from the tail. The egg and sperm nuclei fuse to form one individual nucleus inside a cel ...
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