A - Unity and Diversity
A1.1 Water
A1.2 Nucleic acids
A2.1 Origins of cells (HL)
A2.2 Cell structure
A2.3 Viruses (HL)
A3.1 Diversity of organisms
A3.2 Classification and cladistics (HL)
A4.1 Evolution and speciation
A4.2 Conservation of biodiversity
B - Form and Function
C - Interaction and Interdependence
D - Continuity and Change
View a summary cheatsheet for A1.2 Nucleic acids
A1.2.1 DNA as the genetic material of all living organisms
A1.2.2 Components of a nucleotide
A1.2.3 Sugar–phosphate bonding and the sugar–phosphate “backbone” of DNA and RNA
A1.2.4 Bases in each nucleic acid that form the basis of a code
A1.2.5 RNA as a polymer formed by condensation of nucleotide monomers
A1.2.6 DNA as a double helix linked by hydrogen bonding between complementary base pairs
A1.2.7 Differences between DNA and RNA
A1.2.8 Complementary base pairing in allowing genetic information to be replicated and expressed
A1.2.9 Diversity of possible DNA base sequences and its capacity for storing information
A1.2.10 Conservation of the genetic code as evidence of universal common ancestry
A1.2.11 Directionality of RNA and DNA (HL only)
A1.2.12 Purine-to-pyrimidine bonding as a component of DNA helix stability (HL only)
A1.2.13—Structure of a nucleosome (HL only)
A1.2.14 Evidence from the Hershey–Chase experiment for DNA as the genetic material (HL only)
A1.2.15 Chargaff’s data on pyrimidine and purine bases across diverse life forms (HL only)