(a)[5]
Bacteria living in the root nodules of leguminous plants carry out nitrogen fixation. Describe how nitrogen accessible to these bacteria can eventually be included in animal protein.
(b)[1]
Fig. 2.1 displays the base sequence of a DNA triplet code used to make mRNA. In the space provided, fill in the matching tRNA anticodon. The DNA triplet shown is $\text{TAC}$.
(c)[1]
Cells synthesise more mRNA molecules than tRNA molecules. Suggest one reason for this.
(d)[3]
Describe how ribosomes function during protein synthesis.