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 occurs when the 'baby teeth' (or milk teeth) come through the gums. It is a normal part of development. Although the milk teeth develop when the baby is growing in the womb, the teeth only start to grow throughout the gums when the baby is 6-9 months old (although it can be before or after these ages).