Sperm gene once

A spermatozoon is a male germ cell capable of fertilizing an oocyte and carries genetic information for determining the sex of the offspring. It comprises autosomes and an X X spermatozoa or a Y chromosome Y spermatozoa. The origin and maturation of both X and Y spermatozoa are the same, however, certain differences may exist. Previous studies proposed a substantial difference between X and Y spermatozoa, however, recent studies suggest negligible or no differences between these spermatozoa with respect to ratio, shape and size, motility and swimming pattern, strength, electric charge, pH, stress response, and aneuploidy.

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New Biological Insights on X and Y Chromosome-Bearing Spermatozoa

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Sex and genetic shuffling: details

To form an egg or sperm cell, a cell splits into two during meiosis so each resulting cell only contains half the chromosomes of the original. When parents pass their genes down to their children, they give the kids remixed versions of their own chromosomes. The data in this study may be helpful for understanding mutation rates in humans and measuring how quickly we are evolving. Each chromosome can contain hundreds to thousands of genes, stretches of DNA that spell out the chemical recipes for myriad proteins.
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Gene-swapping in human sperm and eggs can increase genetic mutations in children

Eat poorly, and your body will remember—and possibly pass the consequences onto your kids. Today, in two complementary studies, scientists tell us how. As sperm traverse the male reproductive system, they jettison and acquire non-genetic cargo that fundamentally alters sperm before ejaculation. Each year, over 76, children are born as a result of assisted reproduction techniques, the majority of which involve some type of in vitro fertilization IVF. Multiple variations on IVF exist, but in some cases that involve male infertility—for instance, sperm that struggle to swim—sperm must be surgically extracted from the testes or epididymis, a lengthy, convoluted duct that cradles each testis.
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Sperm is the male reproductive cell , or gamete , in anisogamous forms of sexual reproduction forms in which there is a larger, "female" reproductive cell and a smaller, "male" one. Animals produce motile sperm with a tail known as a flagellum , which are known as spermatozoa , while some red algae and fungi produce non-motile sperm cells, known as spermatia. Sperm cells form during the process known as spermatogenesis , which in amniotes reptiles and mammals takes place in the seminiferous tubules of the testes. The spermatocytes then undergo meiosis , reducing their chromosome number by half, which produces spermatids.
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