Nucleic acids (HL)
DNA and RNA structure, replication and gene expression control.
Review and practiseBIOLOGY HL · Learning hub
Biology HL
HL-only depth: nucleic acids and metabolism, plant biology, genetics and evolution, and animal physiology.
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Key concepts
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Metabolism, respiration and photosynthesis (HL)
Enzyme kinetics, the electron transport chain and the light-dependent and light-independent reactions.
Review and practisePlant biology (HL)
Transport in xylem and phloem, plant hormones and growth responses, and reproduction in flowering plants.
Review and practiseGenetics and evolution (HL)
Meiosis and the origin of genetic variation, patterns of inheritance, and gene pools, selection and speciation.
Review and practiseAnimal physiology (HL)
Antibody production and vaccination, muscle contraction, kidney function and osmoregulation, and sexual reproduction.
Review and practiseStructured progression
Revision Ladder
Start with foundations, then move through application and challenge. Stages use activity marks and complexity.
Stage 1
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Recall core ideas and establish reliable methods.
54 activities availableStage 2
Start stage Apply
Connect concepts and apply them in exam-style contexts.
48 activities availableStage 3
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Topic practice
Recommended next: Nucleic acids (HL)
01
Nucleic acids (HL)
Not startedDNA and RNA structure, replication and gene expression control.
0%0/20 complete
02Metabolism, respiration and photosynthesis (HL)
Not startedEnzyme kinetics, the electron transport chain and the light-dependent and light-independent reactions.
0%0/22 complete
03Plant biology (HL)
Not startedTransport in xylem and phloem, plant hormones and growth responses, and reproduction in flowering plants.
0%0/20 complete
04Genetics and evolution (HL)
Not startedMeiosis and the origin of genetic variation, patterns of inheritance, and gene pools, selection and speciation.
0%0/20 complete
05Animal physiology (HL)
Not startedAntibody production and vaccination, muscle contraction, kidney function and osmoregulation, and sexual reproduction.
0%0/20 complete
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