Roundworms have taken this last body plan and adapted to thousands of environments with it. From microscopic to maybe a meter long, roundworms are just what they sound like-round worms. At one end, they have a mouth, at the other, an anus, with a tube digestive system in between.
Availability of two-factor authentication for Apple ID Two-factor authentication is an extra layer of security for your Apple ID designed to ensure that you're the only person who can access your account, even if someone knows your password.
Two-factor authentication is one of the best things you can do to make sure your accounts don't get hacked. We've talked about it a bit before, but here's a list of all the popular services that offer it, and where you should go to turn it on right now.