The haploid nucleus of a fully mature ovum which loses its nuclear envelope and liberates its chromosomes to meet in the synapses with those similarly derived from the male ...
The open anterior end or the open posterior end of the neural tube of the early embryo. These openings gradually close as the tube develops, the timing of each being so precise ...
Also known as All Hallow's Eve, Halloween is an annual holiday celebrated on October 31st in America, Canada, and the UK. It is supposedly the one day ...
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