In an experimental situation, a student researcher inserts an mRNA molecule into the cytoplasm of a eukaryotic cell after she has removed its 5' cap and poly-A tail. Which of the following would you expect her to find?

a) The mRNA attaches to a ribosome and is translated, but more slowly.

b) The cell adds a new poly-A tail

c) The mRNA is quickly spliced into an mRNA containing a 5

The mRNA would most likely be degraded by nucleases in the cell cytoplasm

Explanation:

The 5'cap on an mRNA strand is necessary to bind ribosomes when the mRNA is being transcribed it also:

The poly-A tail helps to:

Without the cap and tail the mRNA is just a free ranging strand of nucleotides that the cell will try to clean up.

b brown mice / white sand dunes

many other transport proteins, often called pumps, move materials against a concentration gradient. active transport drives molecules across a membrane from a region of lower concentration to a region of higher concentration. this process, shown in figure 5.1, uses transport proteins powered by chemi- cal energy.