When it comes to making babies, it's just about the need for speed.
It has long been said that "strong swimmers" win the day, but new research shows how important it is to be fast in the race for fertilization. This is because zipper sperm are probably the only ones that are fast enough to sneak past the narrow areas of the female reproductive tract.
Scientists use small scales and computer simulations to "study sperm movement" in studies that one day can be used to stimulate male fertility. At the same time, he has created a wonderful semen video that is trying to swim up the stream.
With one ejaculate, 100 million sperm can swim in the female reproductive tract but there are obstructions along the way from the cervix to the egg, known as "striction." They can change the flow of mucus and affect how little boys try to fight the flow.
Researchers from Cornell University built a device for implanting a fallopian tube and used human and bull semen to test it and watch how small swimmers are moving in these difficult places.
They found that the sperm were collected under the opening of the narrow stretch, and the fastest guys in the pack compete with each other, giving them a bigger blow to the finish line while the slower swimmers are caught in the counter currents spraying and driving backwards.
"Accumulation under the stricture is carried out hierarchically, so dense sperm concentrations at higher rates remain closer to the stricter, with less frequent arrays of lower velocity," the researchers wrote.
John Amory, a professor and fertility expert at the University of Washington who did not participate in the study, says this confirms a key issue about the merits of semen gaining.
"We have always been clinically suspected that this is the highly mobile semen responsible for fertilization, and this article suggests that this is the right way to look at things," he said. – This is a very cool little model.
The study was published this week in the magazine Scientific Achievements,