The accompanying illustration shows a portion of a gene undergoing transcription. The template and coding strands for the gene are labeled, and a segment of DNA sequence is given. For this gene segment:

Write the polarity and sequence [TIP 1] of the RNA transcript from the DNA sequence given.

Key Concepts

Transcription

Transcription is the process by which the genetic information encoded in DNA is copied into messenger RNA (mRNA). During transcription, RNA polymerase binds to the DNA template strand and synthesizes a complementary RNA strand, following base-pairing rules where adenine pairs with uracil (instead of thymine) and cytosine pairs with guanine.

Polarity of Nucleic Acids

Nucleic acids, including DNA and RNA, have directionality referred to as polarity, which is defined by the orientation of the sugar-phosphate backbone. The 5' end has a phosphate group, while the 3' end has a hydroxyl group. During transcription, RNA is synthesized in the 5' to 3' direction, meaning the RNA transcript will have a 5' end corresponding to the start of the transcription process.

Base Pairing Rules

Base pairing rules dictate how nucleotides pair with each other during the processes of DNA replication and transcription. In RNA synthesis, adenine (A) in the DNA template pairs with uracil (U) in RNA, while cytosine (C) pairs with guanine (G). Understanding these rules is essential for accurately determining the sequence of the RNA transcript from the given DNA sequence.