Open the combination lock using the old combination. Remove the u-bar from the lock body so it's in the Unlock position. Use a screwdriver to open the anti-dust cover on the back of the combination lock. Align the old combination numbers to the guide points.
A base pair (bp) is a unit consisting of two nucleobases bound to each other by hydrogen bonds. They form the building blocks of the DNA double helix, and contribute to the folded structure of both DNA and RNA.
Complementary base pairing describes the manner in which the nitrogenous bases of the DNA molecules align with each other. Complementary base pairings are also responsible for the double-helix structure of DNA. If you imagine yourself looking at a closet with four pairs of shoes that are all mixed up, complementary base pairing would be the set of rules that you would use to know which shoes go together.