How do sperm know where the egg is?

Question

Weird question but how do they know how to head for the egg? How do they know what to do when they find the egg and how come they don't try and fertilise each other or other or parts of the male sex organs when they're still in the man? Its like they have a mind of their own!

Answer 1

Chemotaxis!
This is the process by which something will move along a concentration gradient.
The egg releases a chemical which will have a higher concentration near the egg, and the concentration will get lower the farther from the egg you go. Spermatozoa (sperm) are attracted by this chemical, and will move along toward the higher concentration until it finds the egg.

Answer 2

Keep in mind that your cells are living in an entirely different world. A dark one. They only know if something happening if they bump into it or get some kind of a chemical whiff... sort of like touch and smell. Which works a lot better than you might think because at the small scale that cells are at, chemicals move around REALLY fast.

Eggs make it easy. They WANT to be found. And sperm cells are IMMENSELY sensitive to the chemical signals that eggs put out (they seem to be able to detect a single molecule of 'scent'). Other sperm and cells don't send out those signals, and they certainly don't 'feel' right when they rub up against them. So there's really no chance that they'll try and fertilize the wrong thing.

Even with that sensitivity, they don't generally know where the egg is when they first get on the scene. Instead they spiral out in all directions until they run into something. There's so many of them, they're pretty much bound to run into an egg if there's one around and they live long enough to get there. Still, a lot of things can go wrong along the way, which is why not every couple is equally fertile.

Hope that helps!

Answer 3

There are millions of them darting around everywhere never asking directions. Finally, one arrives in the right place. It is my opinion that the egg chooses a preferred sperm and latches onto it rather than the other way around. That also explains why they don't try to pollinate (my preference to the word fertilize) each other. They know not what they are doing and simply dart around as fast as possible.

Answer 4

they smell it and they cannot fertilise each other theres nothing to fertilise in the sack so yeah they do have a mind of their own I would say other wise I would have to agree with the first answer "mapquest"

Answer 5

they know it cause the egg emit some kinda smell ( i forget the name) then the sperm will make its way to the egg

Answer 6

Mapquest

Answer 7

God is mysterious, that's why

Answer 8

receptors