IB Biology HL · Unit 4 of 6

IB Biology HL Unit 4: Continuity and change

Unit 4 of IB Biology covers Continuity and change. This unit contains 12 topics and 59 sub-topics. Below you'll find free study notes, flashcards, and exam preparation resources for every topic in this unit.

Higher Level students should treat this unit page as a route map: revise the shared core, then use the HL notes and topic links to reach the extra depth and evaluation expected at HL.

12 topics59 sub-topics

Exam technique guide

Topics in Unit 4

4.1

DNA replication

4 sub-topics

4.2

Protein synthesis

3 sub-topics

4.3

Mutations and gene editing

6 sub-topics

4.4

Cell and nuclear division

5 sub-topics

4.5

Gene expression

5 sub-topics

4.6

Water potential

5 sub-topics

4.7

Reproduction

5 sub-topics

4.8

Inheritance

6 sub-topics

4.9

Homeostasis

5 sub-topics

4.10

Natural selection

4 sub-topics

4.11

Stability and change

5 sub-topics

4.12

Climate change

6 sub-topics

Study tip: Work through the topics in order — each builds on concepts from the one before. Start with notes, then reinforce with flashcards and practice questions.

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