A - Unity and Diversity
B - Form and Function
C - Interaction and Interdependence
D - Continuity and Change
D1.1 DNA replication
D1.2 Protein synthesis
D1.3 Mutations and gene editing
D2.1 Cell and nuclear division
D2.2 Gene expression (HL)
D2.3 Water potential
D3.1 Reproduction
D3.2 Inheritance
D3.3 Homeostasis
D4.1 Natural selection
D4.2 Sustainability and change
D4.3 Climate change
Master D4.1 Natural selection with International Baccalaureate (IB) Biology exam-style questions, flashcards, lessons, and notes. All resources are aligned with the International Baccalaureate (IB) syllabus and designed for both SL and HL students.
D4.1.1 Natural selection as the mechanism driving evolutionary change
D4.1.2 Roles of mutation and sexual reproduction
D4.1.3 Overproduction of offspring and competition for resources
D4.1.4 Abiotic factors as selection pressures
D4.1.5 Differences between individuals in adaptation, survival and reproduction
D4.1.6 Requirement that traits are heritable for evolutionary change to occur
D4.1.7 Sexual selection as a selection pressure in animal species
D4.1.8 Modelling of sexual and natural selection
D4.1.9 Concept of the gene pool (HL)
D4.1.10 Allele frequencies of geographically isolated populations (HL)
D4.1.11 Changes in allele frequency in the gene pool (HL)
D4.1.12 Differences between directional, disruptive and stabilizing selection (HL)
D4.1.13 Hardy–Weinberg equation and calculations of allele or genotype frequencies (HL)
D4.1.14 Hardy–Weinberg conditions (HL)
D4.1.15 Artificial selection by deliberate choice of traits (HL)
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