Why are the strands of a DNA molecule said to be complementary?

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thomaster · Answer

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complementary means to complete. Complementary DNA or cDNA is DNA made from a RNA template. This template has 4 different nucleobases. Each nucleobase can only form a base pair with 1 specific nucleobase. That is why its called complementary, the nucleobases complete eachother to form a basepair. Look at the picture i attached to this anwser. It will help you to understand it.