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Spermatogenesis produces mature male gametes, commonly called sperm but more specifically known as spermatozoa, which are able to fertilize the counterpart female gamete, the oocyte, during conception to produce a single-celled individual known as a zygote.
Sperm (pl.: sperm or sperms) 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 ...
Human sexual reproduction, to produce offspring, begins with fertilization. Successful reproduction typically involves sexual intercourse between a healthy, sexually mature and fertile male and female. [1] During sexual intercourse, sperm cells are ejaculated into the vagina through the penis, resulting in fertilization of an ovum to form a ...
A 1992 World Health Organization report described normal human semen as having a volume of 2 mL or greater, pH of 7.2 to 8.0, sperm concentration of 20×10 6 spermatozoa/mL or more, sperm count of 40×10 6 spermatozoa per ejaculate or more, and motility of 50% or more with forward progression (categories a and b) of 25% or more with rapid ...
Males typically produce billions of sperm each month, [64] many of which are capable of fertilization. Females typically produce one ovum a month that can be fertilized into an embryo. Thus during a lifetime males are able to father a significantly greater number of children than females can give birth to.
Sperm cells normally come in two types, "female" and "male", named for the resulting sex of the fertilized zygote each produces after fusing with the ovum. Sperm cells that produce female (karyotype XX) offspring carry an X-chromosome, while sperm cells that produce male (XY) offspring carry a Y-chromosome. [3]
In all animals, males produce spermatocytes, even hermaphrodites such as C. elegans, which exist as a male or hermaphrodite. In hermaphrodite C. elegans, sperm production occurs first and is then stored in the spermatheca. Once the eggs are formed, they are able to self-fertilize and produce up to 350 progeny. [3]
The external location may also cause a reduction in the heat-induced contribution to the spontaneous mutation rate in male germinal tissue. [6] Sperm are the smaller of the two gametes and are generally very short-lived, requiring males to produce them continuously from the time of sexual maturity until death.