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:
Teething. The time when teething begins varies widely. Most babies are 4 to 7 months old when the first tooth appears, according to the American Academy of Pediatrics. Some little ones may have to wait until they reach 15 months of age. Watch your baby's lower gum when you suspect he is teething. His first tooth will most likely be one of the bottom front teeth.