Polymers are everywhere. Just look around. Your plastic water bottle. The silicone rubber tips on your phone’s earbuds. The nylon and polyester in your jacket or sneakers. The rubber in the tires on the family car. Now take a look in the mirror. Many proteins in your body are polymers, too. Consider keratin (KAIR-uh-tin), the stuff your hair and nails are made from. Even the DNA in your cells is a polymer.
Polymers, whether artificial (such as the plastic shown) or natural, are made of repeating chains of smaller chemical units. Here, carbon atoms are shown as black, oxygen as red and hydrogen as white.