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
So the ratio would be 1:2 or 1:3 if you were comparing length of the sperm to the diameter of the egg. If you compare the width of a sperm cell ( ~3 Âµm) to an egg's diameter the ratio would be between 1:40 -1:50. I have heard that male sperm swim faster and female sperm live longer, is this true? There is some truth to this idea. There is a technique called swim up to help people have some control over the sex of their child, but it is not very effective (ratio from 50/50 to around 60/40 for males/females).