The poly-A tail is a long chain of adenine nucleotides that is added to a messenger RNA (mRNA) molecule during RNA processing to increase the stability of the molecule. Immediately after a gene in ...

There are five different categories of scales — placoid, cosmoid, ganoid, cycloid, and ctenoid — but most commonly eaten fish ...

A cycloidal gear drive is one of the most mesmerizing reduction gears to watch when it is running, but it’s not all just eye-candy. Cycloidals give decent gearing, are relatively compact and ...

"Not only am I a child genius, but I can blow a four-cuspid hypo-cycloid smoke ring." A young man with motley Kentucky side-burns is talking to a pale blonde boy. The side-burns belong to Dan ...