Answer:
The correct answer is
1. 5' end.
2. guanosine
3. 5′ to 5′ triphosphate linkage.
4. On the 7th position.
5. 2′ hydroxy-groups of the first 2 ribose sugars.
Explanation:
The eukaryotic mRNA is processed or modified with a guanosine cap at 5' end and poly-A tail at 3'end before translation.
The process of adding a cap at 5' end of a growing mRNA is known as capping. The process of capping adds guanosine nucleotide at the 5'-end of mRNAs by 5′ to 5′ triphosphate linkage. This guanosine is modified by methylating at the 7th position of the atom. The mRNA is further modified by methylation of first two ribose sugars at their 2′ hydroxy-groups. This capping is advantageous to the sequence as it protects the end from phosphatases and nucleases.