3. Which of the following would not prevent an mRNA from being transported to the rough endoplasmic
reticulum in the cytoplasm?

The ends of the mRNA were not modified.
The mRNA was not correctly spliced
The mRNA was not bound by a ribosome.
The mRNA is for a secreted protein.


5. What type of mutation could cause the 3-nucleotide reading frame of tRNA to be shifted?

switching a normal nucleotide for an abnormal one
deletion of one or more nucleotides during replication
replacing an amino group
incorrect base pairing

Respuesta :

(3)

The ends of the mRNA were not modified.

If mRNA wasn't modified at its end it would even reach the Rough Endoplasmic Reticulum (RER) mainly because it would be degraded by nucleases enzyme.

Explanation:

The modification involves adding a Poly-A tail at its 3’ end and a 5’ cap (7-methylguanosine) at the 5’ end.

If the modification of ends is done but splicing is not, the RNA would still get to the RER but the translation of the nascent mRNA (since it's not mature) would be faulty and would probably stall because the splicing removes introns that are noncoding regions.

(5)

Deletion of one or more nucleotides

Deleting one of two nucleotides on a DNA strand will cause a frameshift mutation. The deletion of 3 nucleotides doesn’t . This is because codons are composed of 3 nucleotide sequences that code for particular amino acids.

Explanation:

A deletion of one or two nucleotides will cause these sequences to change downstream of the mutation. The codon sequences will shift by one base pair if one deletion occurs or by two base pairs if deletion two bass occurred. 3 nucleotide deletion will only delete a codon but the other codon will remain the same.

A substitution mutation would also not cause a frameshift mutation because the codon sequence would still remain the same downstream. Only the codon in which the substitution occurred would be affected.

Learn More:

For more on RNA modification check out;

https://brainly.com/question/9050994

https://brainly.com/question/13975903

For more on frame-shift mutations check out;

https://brainly.com/question/1734026

https://brainly.com/question/11652146

#LearnWithBrainly

3) The mRNA was not bound by a ribosome.

5) Deletion of one or more nucleotides