Scientists often use a procedure known as in vitro translation to make proteins in the laboratory. This procedure uses extracts from animal cells, plant cells or bacteria. These are selected because they have a very high rate of protein synthesis. The cells are processed so that the cell walls, where present, and the cell membranes are broken down, and then treated so that any DNA and mRNA belonging to the cell are destroyed. If mRNA from any source is added to these extracts, it is translated into the matching protein.
(a(i))[2]
Explain why the cells are selected because they carry out protein synthesis at a high rate.
(a(ii))[1]
Explain why the cell walls, if present, and the cell membranes have to be broken down.
(a(iii))[1]
Explain why the cell’s own mRNA must be destroyed.
(a(iv))[2]
Explain why mRNA from any source can be translated in extracts of any kind.
(b)[2]
State two differences between the structures involved in translation in prokaryotes and eukaryotes.
(c)[1]
Scientists usually find that in vitro translation is less efficient than in vivo translation, which takes place inside cells. Suggest a reason for this.
Worked solution & mark scheme
This 9-mark question has a full step-by-step worked solution and mark scheme. One marking point: “Cells contain the apparatus needed for protein synthesis” …