The region of the transcript from the 5’ cap to the nucleode just upstream of the start codon is called the 5’ untranslated region (5’UTR) because it is part of the transcript that isnot translated. How long (in ribonucleotides) is the 5’UTR

In prokaryotes the 5' UTR is 3-10 nucleotides.

In Eukaryotes the 5'UTR is 100 to many thousand nucleotides long.

Explanation:

Leader sequence or 5' UTR starts at transcription site and ends at the initiation codon just one nucleotide away from it.

It is present in mRNA.

These are GC rich and form secondary structure, helps in protein synthesis.

Shine Dalgarno sequence in prokaryotes is an example of 5'UTR.

It acts as an entry point of ribosome.

helicase, i think thats it