complementary strand. noun, Biochemistry. 1. either of the two chains that make up a double helix of DNA, with corresponding positions on the two chains being composed of a pair of complementary bases. 2. a section of one nucleic acid chain that is bonded to another by a sequence of base pairs.
The teething process. Most babies start teething at around six months. However, all babies are different and the timing of teething varies. Some babies are born with their first teeth. Others start teething before they are four months old, and some after 12 months. Early teething should not cause a child any problems, unless it affects their feeding. A rough guide to the different stages of teething is:
At What Age Do Babies Start Teething? According to the American Dental Association (ADA), a baby's first tooth often appears anywhere from eight months to a year of age. The last teeth to grow in are usually the molar, or back teeth, which often start making an appearance anywhere from 13 months all the way up to 33 months.