What feature is on a primary mRNA transcript but not on a mature mRNA transcript?

Explanation: The primary RNA contains introns and exons because it has not been processed yet, and therefore the introns have not been spliced out. Mature mRNA contains only exons, which are the coding sequences that ultimately get translated. Intron regions are non-coding and are not included in mature transcripts.

How does the primary transcript or pre-mRNA differ from mature mRNA in eukaryotic cells?

The major difference between pre-mRNA and mRNA is that pre-mRNA is the immediate product of transcription which is comprised of both exons (coding sequences) and introns (non-coding sequences).

What is the difference between mature mRNA and pre-mRNA?

Pre-mRNA is the primary transcript which contains both coding and non-coding sequences. mRNA is the mature messenger RNA which contains only the coding sequence of a gene. So, this is the key difference between pre-mRNA and mRNA.

Why is the primary transcript longer than the mature mRNA?

The primary transcript is much longer than mature mRNA because of the presence of introns in the former.

Why the primary mRNA transcript is so much shorter than chromosomal DNA?

Why is mRNA shorter than DNA? ➔ mRNA is the transcript of particular region of DNA, generally protein coding region and not of the whole DNA. It also does not contain sequences of exons from DNA. Thus mRNA is shorter than DNA.

How are primary transcripts of eukaryotic mRNA modified into mature mRNA?

This transcript must undergo processing (splicing and addition of 5′ cap and poly-A tail) while it is still in the nucleus in order to become a mature mRNA. The mature mRNA is exported from the nucleus to the cytosol, where it is translated at a ribosome to make a polypeptide.

Which RNA is a primary transcript?

mRNAs
A primary transcript is the single-stranded ribonucleic acid (RNA) product synthesized by transcription of DNA, and processed to yield various mature RNA products such as mRNAs, tRNAs, and rRNAs. The primary transcripts designated to be mRNAs are modified in preparation for translation.

How is pre-mRNA different from the final mRNA transcript that will leave the nucleus?

In the nucleus, a pre-mRNA is produced through transcription of a region of DNA from a linear chromosome. This transcript must undergo processing (splicing and addition of 5′ cap and poly-A tail) while it is still in the nucleus in order to become a mature mRNA.

Which of the following ways is a primary mRNA transcript modified in eukaryotes?

The primary transcript of a eukaryotic gene is modified in several ways before it leaves the nucleus: both ends of the pre- mRNA are modified, and the introns are removed. In eukaryotes, there is usually a “polyad- enylation” sequence (AAUAAA) near the 3′ end of the pre- mRNA, after the last codon.

What happens to the transcript RNA before it leaves the nucleus?

Transcription takes place in the nucleus. It uses DNA as a template to make an RNA molecule. RNA then leaves the nucleus and goes to a ribosome in the cytoplasm, where translation occurs. Translation reads the genetic code in mRNA and makes a protein.

How does transcription produce different mature mRNA transcripts?

Alternative RNA splicing The benefit of RNA splicing is that one gene can produce many different proteins as a result of what segments are treated as introns and exons. Different exons result in different mature transcripts and produce different proteins.