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Sperm storage organs in the fruit fly Drosophila melanogaster.Female was first mated with GFP-male and then re-mated with RFP-male. Female sperm storage is a biological process and often a type of sexual selection in which sperm cells transferred to a female during mating are temporarily retained within a specific part of the reproductive tract before the oocyte, or egg, is fertilized.
The human sperm cell is haploid, so that its 23 chromosomes can join the 23 chromosomes of the female egg to form a diploid cell with 46 paired chromosomes. In mammals, sperm is stored in the epididymis and released through the penis in semen during ejaculation. The word sperm is derived from the Greek word σπέρμα, sperma, meaning "seed".
Penile-vaginal intercourse or vaginal intercourse is a form of penetrative sexual intercourse in human sexuality, in which an erect penis is inserted into a vagina. [1] Synonyms are: vaginal sex, cohabitation, coitus (Latin: coitus per vaginam), (in elegant colloquial language) intimacy, or (poetic) lovemaking.
The sperm (being one of approximately 250 million sperm in a typical ejaculation) travels through the vagina and cervix into the uterus or fallopian tubes. Only 1 in 14 million of the ejaculated sperm will reach the fallopian tube. The egg simultaneously moves through the fallopian tube away from the ovary.
Sperm cells can live inside a female's body for up to five days, and once ovulation occurs, the egg remains viable for 12–48 hours before it begins to disintegrate. [4] Superfecundation most commonly happens within hours or days of the first instance of fertilization with ova released during the same cycle.
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 ...
Internal fertilization is the union of an egg and sperm cell during sexual reproduction inside the female body. Internal fertilization, unlike its counterpart, external fertilization , brings more control to the female with reproduction. [ 1 ]
There is also considerable variability in this interval, with a 95% prediction interval of the ovulation of 9 to 20 days after menstruation even for an average woman who has a mean LMP-to-ovulation time of 14.6. [32] In a reference group representing all women, the 95% prediction interval of the LMP-to-ovulation is 8.2 to 20.5 days. [31]