Hummmm yummy yummy. I actually enjoy this post. I just have a good understanding of how fertilization take place. I also get to know what might leads to infertility in human,so if the sperm is not strong enough, it may not be able to penetrate through the three layers and then fertilize.

And I think it's good the way the maker of all things made each specie such that unguided crossbreeding will not result to monster! Imagine if lion and tiger can mate naturally!!

@gentleshaid, this is really trilling , welcome back after a very lonnnnnnnnng time.
Really missed you.