Egg-Laying Sharks. Of the approximately 400 species of sharks, about 40% lay eggs. This is called oviparity. When the eggs are laid, they are in a protective egg case (which sometimes washes up on the beach and is commonly called a mermaid's purse).
what s the truth i am asking this b c there seems to be posts on here that say y sperm swim faster which is what we all prob have heard for the longest time but there have been some recent posts on here that state newer studies now say y sperm aren t any faster than x and they can both swim just as fast so im just wanting to know which one is true if anyone really knows thanks
Sperm transport through the uterus. At only a few centimetres in length, the human uterine cavity is relatively small and could be traversed in less than 10 min by sperm swimming at about 5 mm/min, which is the swimming speed of sperm in aqueous medium (Mortimer and Swan, 1995).