The DNA molecule is a double-stranded helix structure composed of four nucleotide bases: adenine (A), guanine (G), cytosine (C), and thymine (T). The arrangement of these four bases is the code that determines the genetic information of an organism. The two strands of the DNA molecule are complementary to each other, meaning that the sequence of bases on one strand determines the sequence on the other.
The two strands of the DNA molecule are distinguished by their orientation relative to each other. One strand is called the template strand, and the other is called the coding strand. The template strand serves as the blueprint for the synthesis of RNA, whereas the coding strand is identical in sequence to the RNA except that it contains the base thymine instead of uracil (U).
During transcription, RNA polymerase, an enzyme that reads the DNA sequence, binds to the template strand and synthesizes RNA by pairing the complementary nucleotides with the DNA template. This process results in the formation of a single-stranded RNA molecule that is complementary to the template strand.
The coding strand, on the other hand, is not directly involved in the transcription process but is important in determining the sequence of the RNA product. The coding strand has the same sequence as the RNA except that it contains thymine instead of uracil. Thus, the sequence of the coding strand can be used to predict the sequence of the RNA that will be synthesized.
In summary, the template strand is the DNA strand that is used as a template for the synthesis of RNA, whereas the coding strand is the complementary strand to the template strand that contains the same sequence as the RNA product. The distinction between the two strands is important in understanding the transcription process and the synthesis of RNA from DNA.
