Human Sexual Reproduction
June 9, 2008
Human Sexual reproduction is characterized by processes that pass a combination of genetic material to offspring, resulting in diversity.
The main two processes are: meiosis, involving the halving of the number of chromosomes; and fertilization, involving the fusion of two gametes and the restoration of the original number of chromosomes. During meiosis, the chromosomes of each pair usually cross over to achieve genetic recombination.
Human Sexual reproduction, which includes human sexual reproduction and most other animal reproduction, requires the participation of two individuals of the opposite sex. During sexual reproduction, an embryo is formed when an egg carried by the female is fertilized by the male (as during human reproduction).
During sexual intercourse, a man releases approximately 300 million sperm into a woman’s vagina, but only one of the sperm can fertilize the ovum. The successful sperm cell must enter the uterus, swim up the fallopian tube (a trumpet-shaped passageway between the ovary and the uterus) to meet the ovum, and then pass through a thick coating, known as the zona pellucida, that surrounds the egg. The head of the sperm cell contains enzymes (a type of proteins that speeds up chemical reactions—sees Enzymes) that break through the zona pellucida and allow the sperm to penetrate the egg. Once the head of the sperm is inside the egg, the tail falls off, and the outside of the egg thickens to prevent another sperm from entering. Many variables affect whether fertilization occurs after intercourse among humans. One factor is a woman’s ovulatory, or menstrual, cycle. Human eggs can be fertilized for only a few days after ovulation, which typically occurs only once every 28 days. (To learn about what happens after fertilization, see Pregnancy and Birth.)
The long journey to fertilization must be completed within 12 to 48 hours, before the sperm die. They must first cross the barrier of the cervix, which will be thin and watery if the woman has just ovulated (for our purposes, we will assume that sexual intercourse has occurred within a couple of hours after ovulation).
Once the sperm have traversed the cervical mucus, they travel up the moist lining of the uterus into the Fallopian tubes (only one of the Fallopian tubes contains an egg, so many sperm travel in the wrong direction). Fewer than 1,000 sperm out of the millions in the semen actually reach the Fallopian tubes.
Now you have learned that how Human sexual reproduction works.
Asparagus is said to be one of the most helpful herbs for women
Some of the most important indications are as below –
- works mainly on the circulatory, digestive, respiratory and female reproductive organs
- The best female reproductive tonic
- Any burning problems including hyperacidity and various ulcers
- An eye tonic
Tribulus Terrestris for Low Libido
The herb has been in use treating various health ailments such as -
- Urinary Genital Support
- Energy and stamina
- Libido and sexual behavior enhancer
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