IB Biology HL 1.2.8 Complementary Base Pairing Question Bank
Practise IB Biology HL 1.2.8 by deducing unknown bases and bonds, then linking complementary pairing to accurate genetic copying.
- Syllabus
- First assessment 2025
- Course
- Biology HL
- Level
- HL
Practise IB Biology HL 1.2.8 by deducing unknown bases and bonds, then linking complementary pairing to accurate genetic copying.
The diagram shows a nucleic acid, with some of the bases indicated.

Deduce the base indicated by X on the diagram.
cytosine / C;
Identify the type of bond indicated by Z on the diagram.
covalent/phosphodiester;