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Originally Posted by wedouglas
nah, you have only 1. each sperm is different. come on, common sense here
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You're correct from a strictly scientific point of view.
Remember that in humans both sperm and egg are haploid; that is, they carry only half the number of chromosomes (23) as a normal cell (46) in the body. When sperm and egg unite they form the diploid (two sets of chromosomes) zygote; the zygote obtains one set of chromosomes from the egg and one from the sperm.
During the production of the sperm or egg cells (the gametes), a diploid cell undergoes two successive cell divisions during meiosis to give four haploid gametes. Prior to the first divison in meiosis, the diploid cell replicates its set of 46 chromosomes and all of the chromosomes "pair off" with their nearly identical copy; during this period, individual pieces of DNA that make up the chromosomes can "cross-over" or become associated with one of its partner chromsomes. This can lead to physical breakage and rejoining of pieces of chromosomes to produce nearly identical, but still slightly different copies of the same chromosome. Since each gamete (sperm or egg) will receive only one of the four nearly identical copies of each chromosome in the set, each individual sperm or egg is slightly different at the DNA level.
However, nature or nurture? Would a child with nearly identical DNA raised exactly the same way you were turn out to be you?