Sperm journey to fertilization

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A little about the video
Fertilization , union of a spermatozoal nucleus , of paternal origin, with an egg nucleus, of maternal origin, to form the primary nucleus of an embryo. In all organisms the essence of fertilization is, in fact, the fusion of the hereditary material of two different sex cells , or gametes , each of which carries half the number of chromosomes typical of the species. The most primitive form of fertilization, found in microorganisms and protozoans, consists of an exchange of genetic material between two cells. The first significant event in fertilization is the fusion of the membranes of the two gametes, resulting in the formation of a channel that allows the passage of material from one cell to the other. Fertilization in advanced plants is preceded by pollination , during which pollen is transferred to, and establishes contact with, the female gamete or macrospore. Fusion in advanced animals is usually followed by penetration of the egg by a single spermatozoon.
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What Are the Steps of Fertilization in Humans?

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fertilization | Steps, Process, & Facts | daddeldepot.com

About 20 per cent of cases are due to male infertility , and some couples have a combination of male and female problems contributing to difficulties conceiving. Sometimes there is no cause found. Infertility is a common problem, affecting about one in 6 couples in Australia. Infertility is defined by doctors as not having conceived after 12 months of having regular unprotected sex. There are treatments available to help address many causes of female infertility, and there is also assisted reproductive technology, such as IVF, that can help some women get pregnant. The only symptom may be difficulty getting pregnant. However, some women may have other signs of fertility problems, such as an irregular menstrual cycle or not having periods at all.
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Fertilization

Fig 1. The journey begins with millions of sperm cells that are released into the female reproductive tract during intercourse. The sperm cells gain their full ability to swim when they are ejaculated into the reproductive tract [ 1 ],[ 2 ]. Upon ejaculation, the sperm cells are enclosed in a fluid called seminal plasma or semen, which is a mix of fluids from the testes, seminal vesicles, prostate, and the bulbourethral glands. The fluid contains elements which protect the sperm cells during their journey towards the egg.
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Achieving a healthy pregnancy is a complicated, multi-stage process involving two people. Every month, the female ovulates one mature egg from one of her ovaries. Here, it will begin to move slowly down the tube towards the womb uterus. However, for a pregnancy to develop it must first meet sperm from the male whilst it is still held in the fallopian tube.
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