Source: https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/14-1-2-types-of-rna [Revision notes](https://senecalearning.com/en-gb/revision-notes.md) › [IB Diploma](https://senecalearning.com/en-gb/revision-notes/ib-diploma.md) › [Biology](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology.md) › [Biology: IB Diploma](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma.md) › Types of RNA # Types of RNA Biology: IB Diploma Higher Level, topic 14.1.2 ## Types of RNA RNA is a single-stranded nucleic acid molecule that is made from the same bases as DNA except for uracil (U) which is used instead of thymine (T). There are different types of RNA: ### mRNA ![mRNA](https://image-v2.cdn.app.senecalearning.com/2018-08/5c68341e-9543-4383-a03b-dd0ddfeac546/mRNA.jpg) - Messenger RNA (mRNA) is transcribed from DNA in the nucleus to produce a single-stranded RNA. - The mRNA strand is complementary to the DNA base sequence. - mRNA travels from the nucleus to the ribosomes in the cytoplasm. - Ribosomes are proteins that translate mRNA into amino acids and synthesize the polypeptide. ### tRNA ![tRNA](https://image-v2.cdn.app.senecalearning.com/2018-08/798bd80b-e155-4873-95ef-512f1224a163/tRNA.jpg) - Transfer RNA (tRNA) forms a clover-like shape and is vital for translation. - tRNA reads the mRNA codons and brings the corresponding amino acid into the ribosomes. ### Accuracy of tRNA ![Accuracy of tRNA](https://image-v2.cdn.app.senecalearning.com/2018-08/798bd80b-e155-4873-95ef-512f1224a163/tRNA.jpg) - It is important that the correct amino acid is brought to the ribosomes by tRNA so that the protein is assembled correctly. - Each tRNA molecule has an anticodon which is complementary to a specific codon on mRNA. - The amino acid that corresponds to a specific anticodon binds to a specific attachment site on the tRNA molecule. ### DNA → amino acid ![DNA → amino acid](https://image-v2.cdn.app.senecalearning.com/2018-08/ab74f1a1-2bfe-43df-b588-3f49d3b98d2d/DNA%20Triplets.jpg) - There are many processes in producing an amino acid from the original DNA sequence. - If the original DNA sequence has the codon GCC, the codon in each step is: - DNA codon: GCC. - mRNA complementary codon: CGG. - tRNA anticodon: GCC. - Amino acid: Arginine. ### rRNA ![rRNA](https://image-v2.cdn.app.senecalearning.com/2018-09/a4aab02a-1911-47bd-82c6-7ca69f190e87/protein-synthesis-translation-mrna-polypeptide-ribosome-.jpg) - Ribosomal RNA (rRNA) is a key component of ribosomes. - rRNA is hence vital for protein synthesis to occur. ## Test yourself on Types of RNA - What feature of tRNA molecules ensures each tRNA binds to the correct codon? - Which of the following statements about RNA are true? - If the DNA codon is CAG, what will the mRNA complementary codon be? [Practise this topic for free](https://app.senecalearning.com/classroom/course/549189f7-f13a-4c5c-b80c-ea1bd3036d78/section/54899b7b-08d2-41a7-9ef5-44d107668b79/session) - Previous topic: [14.1.1 Introduction to Transcription & Protein Synthesis](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/14-1-1-introduction-to-transcription-and-protein-synthesis.md) - Next topic: [14.1.3 Transcription](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/14-1-3-transcription.md) ## Biology: IB Diploma Higher Level contents ### 1 Unity & Diversity - Molecules - 1.1 Water - [1.1.1 The Importance of Water](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/1-1-1-the-importance-of-water.md) - [1.1.2 The Structure of Water](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/1-1-2-the-structure-of-water.md) - [1.1.3 The Properties of Water](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/1-1-3-the-properties-of-water.md) - [1.1.4 IB Multiple Choice - Water & Hydrogen Bonding](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/1-1-4-ib-multiple-choice-water-and-hydrogen-bonding.md) - [1.1.5 Extended Response - Water](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/1-1-5-extended-response-water.md) - 1.2 DNA Structure & Replication - [1.2.1 DNA](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/1-2-1-dna.md) - [1.2.2 RNA](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/1-2-2-rna.md) - [1.2.3 Semi-Conservative DNA Replication](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/1-2-3-semi-conservative-dna-replication.md) - [1.2.4 DNA Replication](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/1-2-4-dna-replication.md) - [1.2.5 DNA Replication - Summary](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/1-2-5-dna-replication-summary.md) - [1.2.6 IB Multiple Choice - DNA Replication](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/1-2-6-ib-multiple-choice-dna-replication.md) - 1.3 Transcription & Gene Expression - [1.3.1 Introduction to Transcription & Protein Synthesis](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/1-3-1-introduction-to-transcription-and-protein-synthesis.md) - [1.3.2 Types of RNA](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/1-3-2-types-of-rna.md) - [1.3.3 Transcription](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/1-3-3-transcription.md) - [1.3.4 RNA Processing in Eukaryotes](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/1-3-4-rna-processing-in-eukaryotes.md) - [1.3.5 IB Multiple Choice - Transcription](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/1-3-5-ib-multiple-choice-transcription.md) - 1.4 Translation - [1.4.1 Translation](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/1-4-1-translation.md) - [1.4.2 Retroviruses](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/1-4-2-retroviruses.md) - [1.4.3 Scientific Practices: Coronavirus](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/1-4-3-scientific-practices-coronavirus.md) - [1.4.4 IB Multiple Choice - Translation](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/1-4-4-ib-multiple-choice-translation.md) ### 2 Unity & Diversity - Cells - 2.1 The Origin of Cells - [2.1.1 Origins - Endosymbiosis](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/2-1-1-origins-endosymbiosis.md) - 2.2 Introduction to Cells - [2.2.1 Introduction to Cells](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/2-2-1-introduction-to-cells.md) - [2.2.2 Cell Size & Surface Area](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/2-2-2-cell-size-and-surface-area.md) - [2.2.3 Surface Area to Volume Ratio](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/2-2-3-surface-area-to-volume-ratio.md) - [2.2.4 Eukaryotic vs Prokaryotic Cells](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/2-2-4-eukaryotic-vs-prokaryotic-cells.md) - [2.2.5 Stem Cells](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/2-2-5-stem-cells.md) - [2.2.6 Stem Cells in Disease](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/2-2-6-stem-cells-in-disease.md) - 2.3 Ultrastructure of Cells - [2.3.1 Golgi, Lysosomes & Ribosomes](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/2-3-1-golgi-lysosomes-and-ribosomes.md) - [2.3.2 Cell Walls & Vacuole](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/2-3-2-cell-walls-and-vacuole.md) - [2.3.3 Prokaryotes](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/2-3-3-prokaryotes.md) - [2.3.4 Binary Fission](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/2-3-4-binary-fission.md) - 2.4 Cell Division - [2.4.1 The Cell Cycle](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/2-4-1-the-cell-cycle.md) - [2.4.2 Mitosis](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/2-4-2-mitosis.md) - [2.4.3 Regulation of the Cell Cycle](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/2-4-3-regulation-of-the-cell-cycle.md) - [2.4.4 End of Topic Quiz - The Cell Cycle](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/2-4-4-end-of-topic-quiz-the-cell-cycle.md) - [2.4.5 IB Multiple Choice - The Cell Cycle](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/2-4-5-ib-multiple-choice-the-cell-cycle.md) - [2.4.6 Extended Response - Mitosis](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/2-4-6-extended-response-mitosis.md) - 2.5 Structure of DNA & RNA - [2.5.1 DNA & RNA](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/2-5-1-dna-and-rna.md) - 2.6 DNA Replication, Transcription & Translation - [2.6.1 Protein Synthesis](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/2-6-1-protein-synthesis.md) - [2.6.2 Transcription & Translation](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/2-6-2-transcription-and-translation.md) - [2.6.3 End of Topic Test - DNA, Genes & Protein Synthesis](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/2-6-3-end-of-topic-test-dna-genes-and-protein-synthesis.md) - [2.6.4 Exam-Style Question - Protein Synthesis](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/2-6-4-exam-style-question-protein-synthesis.md) - [2.6.5 End of Topic Test - Coronavirus Translation](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/2-6-5-end-of-topic-test-coronavirus-translation.md) - [2.6.6 IB Multiple Choice - Transcription](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/2-6-6-ib-multiple-choice-transcription.md) - [2.6.7 IB Multiple Choice - Translation](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/2-6-7-ib-multiple-choice-translation.md) - 2.7 Cell Respiration - [2.7.1 Overview of Respiration](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/2-7-1-overview-of-respiration.md) - [2.7.2 Anaerobic Respiration](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/2-7-2-anaerobic-respiration.md) - [2.7.3 End of Topic Test - Anaerobic Respiration](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/2-7-3-end-of-topic-test-anaerobic-respiration.md) - [2.7.4 Respiration Experiments](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/2-7-4-respiration-experiments.md) - [2.7.5 End of Topic Test - Respiration](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/2-7-5-end-of-topic-test-respiration.md) - [2.7.6 IB Multiple Choice - Respiration](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/2-7-6-ib-multiple-choice-respiration.md) - 2.8 Photosynthesis - [2.8.1 Overview of Photosynthesis](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/2-8-1-overview-of-photosynthesis.md) - 2.9 Viruses - [2.9.1 Viruses](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/2-9-1-viruses.md) ### 3 Unity & Diversity - Organisms - 3.1 Diversity of Organisms - [3.1.1 Chromosomal Theory of Inheritance](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/3-1-1-chromosomal-theory-of-inheritance.md) - [3.1.2 Chromosomal Basis of Inherited Disorders](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/3-1-2-chromosomal-basis-of-inherited-disorders.md) - [3.1.3 IB Multiple Choice - Chromosomal Inheritance](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/3-1-3-ib-multiple-choice-chromosomal-inheritance.md) - 3.2 Evidence for Evolution - [3.2.1 Evidence for Evolution - Fossils & DNA](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/3-2-1-evidence-for-evolution-fossils-and-dna.md) - [3.2.2 Evidence for Evolution - Anatomy & Geography](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/3-2-2-evidence-for-evolution-anatomy-and-geography.md) - [3.2.3 IB Multiple Choice - Evidence for Evolution](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/3-2-3-ib-multiple-choice-evidence-for-evolution.md) - [3.2.4 Extended Response - DNA & Evolution](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/3-2-4-extended-response-dna-and-evolution.md) - 3.3 Natural Selection - [3.3.1 Introduction](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/3-3-1-introduction.md) - [3.3.2 Evolutionary Fitness](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/3-3-2-evolutionary-fitness.md) - [3.3.3 Natural Selection & Variation](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/3-3-3-natural-selection-and-variation.md) - [3.3.4 End of Topic Quiz - Natural Selection](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/3-3-4-end-of-topic-quiz-natural-selection.md) - [3.3.5 IB Multiple Choice - Natural Selection](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/3-3-5-ib-multiple-choice-natural-selection.md) - [3.3.6 Speciation](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/3-3-6-speciation.md) ### 4 Unity & Diversity - Ecosystems - 4.1 Classification - [4.1.1 Introduction to Biodiversity](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/4-1-1-introduction-to-biodiversity.md) - [4.1.2 Keystone Species](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/4-1-2-keystone-species.md) - [4.1.3 Courtship & Ancestry](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/4-1-3-courtship-and-ancestry.md) - [4.1.4 Classification](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/4-1-4-classification.md) - 4.2 Cladistics - [4.2.1 Evolutionary Relationships](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/4-2-1-evolutionary-relationships.md) - [4.2.2 IB Multiple Choice - Species & Taxonomy](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/4-2-2-ib-multiple-choice-species-and-taxonomy.md) - 4.3 Evolution & Speciation - [4.3.1 Evidence for Evolution - Fossils & DNA](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/4-3-1-evidence-for-evolution-fossils-and-dna.md) - [4.3.2 Evidence for Evolution - Anatomy & Geography](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/4-3-2-evidence-for-evolution-anatomy-and-geography.md) - [4.3.3 IB Multiple Choice - Evidence for Evolution](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/4-3-3-ib-multiple-choice-evidence-for-evolution.md) - [4.3.4 Extended Response - DNA & Evolution](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/4-3-4-extended-response-dna-and-evolution.md) - [4.3.5 Populations](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/4-3-5-populations.md) - [4.3.6 Mutations, Genetic Drift, & Gene Flow](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/4-3-6-mutations-genetic-drift-and-gene-flow.md) - [4.3.7 Speciation](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/4-3-7-speciation.md) - [4.3.8 Rate of Speciation](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/4-3-8-rate-of-speciation.md) - [4.3.9 Allopatric & Sympatric Speciation](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/4-3-9-allopatric-and-sympatric-speciation.md) - 4.4 Conservation of Biodiversity - [4.4.1 Coming Soon!](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/4-4-1-coming-soon.md) ### 5 Form & Function - Molecules - 5.1 Carbohydrates & Lipids - [5.1.1 Monosaccharides](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/5-1-1-monosaccharides.md) - [5.1.2 Disaccharides & Polysaccharides](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/5-1-2-disaccharides-and-polysaccharides.md) - [5.1.3 Triglycerides & Phospholipids](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/5-1-3-triglycerides-and-phospholipids.md) - [5.1.4 Cellulose](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/5-1-4-cellulose.md) - [5.1.5 Starch & Glycogen](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/5-1-5-starch-and-glycogen.md) - 5.2 Proteins - [5.2.1 Structure & Functions of Proteins](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/5-2-1-structure-and-functions-of-proteins.md) ### 6 Form & Function - Cells - 6.1 Membranes & Membrane Transport - [6.1.1 Passive Movement Across Membranes](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/6-1-1-passive-movement-across-membranes.md) - [6.1.2 Active Movement Across Membranes](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/6-1-2-active-movement-across-membranes.md) - [6.1.3 Endocytosis & Exocystosis](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/6-1-3-endocytosis-and-exocystosis.md) - [6.1.4 Cell Membrane Structure & Permeability](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/6-1-4-cell-membrane-structure-and-permeability.md) - 6.2 Organelles & Compartmentalization - [6.2.1 Eukaryotic Cells & Organelles](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/6-2-1-eukaryotic-cells-and-organelles.md) - [6.2.2 Subcellular Components & Organelles](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/6-2-2-subcellular-components-and-organelles.md) - 6.3 Cell Specialization - [6.3.1 Cell Specialization](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/6-3-1-cell-specialization.md) ### 7 Form & Function - Organisms - 7.1 Gas Exchange - [7.1.1 Lung Structure & Alveoli](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/7-1-1-lung-structure-and-alveoli.md) - [7.1.2 Ventilation](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/7-1-2-ventilation.md) - [7.1.3 Lung Disease](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/7-1-3-lung-disease.md) - [7.1.4 Lung Disease Data](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/7-1-4-lung-disease-data.md) - 7.2 Transport - [7.2.1 The Circulatory System](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/7-2-1-the-circulatory-system.md) - [7.2.2 The Heart](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/7-2-2-the-heart.md) - [7.2.3 Blood Vessels](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/7-2-3-blood-vessels.md) - [7.2.4 Cardiovascular Disease](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/7-2-4-cardiovascular-disease.md) - [7.2.5 Xylem Structure](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/7-2-5-xylem-structure.md) - [7.2.6 Cohesion-Tension Theory](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/7-2-6-cohesion-tension-theory.md) - [7.2.7 Investigating Transpiration Rate](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/7-2-7-investigating-transpiration-rate.md) - [7.2.8 Phloem Structure](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/7-2-8-phloem-structure.md) - [7.2.9 Translocation](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/7-2-9-translocation.md) - 7.3 Muscle & Motility - [7.3.1 Skeletal Muscle](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/7-3-1-skeletal-muscle.md) - [7.3.2 Sliding Filament Theory](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/7-3-2-sliding-filament-theory.md) - [7.3.3 Contraction](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/7-3-3-contraction.md) ### 8 Form & Function - Ecosystems - 8.1 Species, Communities & Ecosytems - [8.1.1 Population Dynamics](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/8-1-1-population-dynamics.md) - [8.1.2 Communities & Measuring Diversity](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/8-1-2-communities-and-measuring-diversity.md) - [8.1.3 Relationships Between Populations](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/8-1-3-relationships-between-populations.md) - [8.1.4 Overview of Ecosystems](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/8-1-4-overview-of-ecosystems.md) - [8.1.5 Nutrient Cycles](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/8-1-5-nutrient-cycles.md) - [8.1.6 Fertilisers](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/8-1-6-fertilisers.md) - [8.1.7 Eutrophication](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/8-1-7-eutrophication.md) - [8.1.8 Chi-Squared Test](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/8-1-8-chi-squared-test.md) - 8.2 Energy Flow - [8.2.1 Energy](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/8-2-1-energy.md) - [8.2.2 Energy Flow](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/8-2-2-energy-flow.md) - [8.2.3 Biomass & Food Chains](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/8-2-3-biomass-and-food-chains.md) - [8.2.4 Heterotrophs & Autotrophs](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/8-2-4-heterotrophs-and-autotrophs.md) - 8.3 Carbon Cycle - [8.3.1 Carbon Cycle](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/8-3-1-carbon-cycle.md) - 8.4 Climate Change - [8.4.1 Carbon Dioxide](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/8-4-1-carbon-dioxide.md) - [8.4.2 The Greenhouse Effect](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/8-4-2-the-greenhouse-effect.md) - [8.4.3 Global Warming](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/8-4-3-global-warming.md) - [8.4.4 Maintaining Biodiversity](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/8-4-4-maintaining-biodiversity.md) ### 9 Interaction & Interdependence - Molecules - 9.1 Enzymes - [9.1.1 Enzymes](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/9-1-1-enzymes.md) - [9.1.2 Factors Affecting Enzyme Activity](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/9-1-2-factors-affecting-enzyme-activity.md) - [9.1.3 Enzyme-Controlled Reactions](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/9-1-3-enzyme-controlled-reactions.md) - [9.1.4 End of Topic Test - Enzymes](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/9-1-4-end-of-topic-test-enzymes.md) - 9.2 Metabolism - [9.2.1 Molecules to Metabolism](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/9-2-1-molecules-to-metabolism.md) - 9.3 Cell Respiration - [9.3.1 Glycolysis](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/9-3-1-glycolysis.md) - [9.3.2 Aerobic Respiration](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/9-3-2-aerobic-respiration.md) - 9.4 Photosynthesis - [9.4.1 Light-Dependent Reaction](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/9-4-1-light-dependent-reaction.md) - [9.4.2 Light-Independent Reaction](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/9-4-2-light-independent-reaction.md) - [9.4.3 End of Topic Test - Photosynthesis Reactions](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/9-4-3-end-of-topic-test-photosynthesis-reactions.md) - [9.4.4 Limiting Factors](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/9-4-4-limiting-factors.md) - [9.4.5 Photosynthesis Experiments](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/9-4-5-photosynthesis-experiments.md) - [9.4.6 End of Topic Test - Photosynthesis](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/9-4-6-end-of-topic-test-photosynthesis.md) - [9.4.7 End of Topic Test - Photosynthesis](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/9-4-7-end-of-topic-test-photosynthesis.md) ### 10 Interaction & Interdependence - Cells - 10.1 Chemical Signalling - [10.1.1 Coming Soon!](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/10-1-1-coming-soon.md) - 10.2 Neural Signalling - [10.2.1 Medical Application](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/10-2-1-medical-application.md) - [10.2.2 Speed of Transmission](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/10-2-2-speed-of-transmission.md) - [10.2.3 Synapses](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/10-2-3-synapses.md) - [10.2.4 End of Topic Test - Nervous Comm&Coord](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/10-2-4-end-of-topic-test-nervous-commandcoord.md) - [10.2.5 Neuron Structure](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/10-2-5-neuron-structure.md) - [10.2.6 Types of Synapse](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/10-2-6-types-of-synapse.md) - [10.2.7 End of Topic Test - Neurones & Action Potentials](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/10-2-7-end-of-topic-test-neurones-and-action-potentials.md) - [10.2.8 Transmission of an Impulse](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/10-2-8-transmission-of-an-impulse.md) - [10.2.9 End of Topic Test - Synapses](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/10-2-9-end-of-topic-test-synapses.md) - 10.3 Adaptation to Environment - [10.3.1 Coming Soon!](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/10-3-1-coming-soon.md) - 10.4 Ecological Niches - [10.4.1 Coming Soon!](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/10-4-1-coming-soon.md) ### 11 Interaction & Interdependence - Organisms - 11.1 Integration of Body Systems - [11.1.1 Plant Tropisms](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/11-1-1-plant-tropisms.md) - 11.2 Defence Against Disease - [11.2.1 Immune System](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/11-2-1-immune-system.md) - [11.2.2 The Immune Response](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/11-2-2-the-immune-response.md) - [11.2.3 Antibodies](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/11-2-3-antibodies.md) - [11.2.4 Primary & Secondary Response](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/11-2-4-primary-and-secondary-response.md) - [11.2.5 Vaccines](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/11-2-5-vaccines.md) - [11.2.6 HIV](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/11-2-6-hiv.md) - [11.2.7 End of Topic Test - Immune System](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/11-2-7-end-of-topic-test-immune-system.md) ### 12 Interaction & Interdependence - Ecosystems - 12.1 Populations & Communities - [12.1.1 Coming Soon!](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/12-1-1-coming-soon.md) - 12.2 Transfers of Energy & Matter - [12.2.1 Coming Soon!](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/12-2-1-coming-soon.md) ### 13 Continuity & Change - Molecules - 13.1 DNA Replication - [13.1.1 DNA Replication](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/13-1-1-dna-replication.md) - 13.2 Protein Synthesis - [13.2.1 Protein Synthesis](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/13-2-1-protein-synthesis.md) - [13.2.2 Transcription & Translation](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/13-2-2-transcription-and-translation.md) - [13.2.3 End of Topic Test - DNA, Genes & Protein Synthesis](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/13-2-3-end-of-topic-test-dna-genes-and-protein-synthesis.md) - 13.3 Mutation & Gene Editing - [13.3.1 Genes](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/13-3-1-genes.md) - [13.3.2 Mutations](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/13-3-2-mutations.md) - [13.3.3 DNA Technology](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/13-3-3-dna-technology.md) - [13.3.4 PCR & Gel Electrophoresis](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/13-3-4-pcr-and-gel-electrophoresis.md) - [13.3.5 Genetic Modification](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/13-3-5-genetic-modification.md) - [13.3.6 Cloning](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/13-3-6-cloning.md) ### 14 Continuity & Change - Cells - 14.1 Gene Expression - [14.1.1 Introduction to Transcription & Protein Synthesis](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/14-1-1-introduction-to-transcription-and-protein-synthesis.md) - [14.1.2 Types of RNA](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/14-1-2-types-of-rna.md) - [14.1.3 Transcription](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/14-1-3-transcription.md) - [14.1.4 RNA Processing in Eukaryotes](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/14-1-4-rna-processing-in-eukaryotes.md) - [14.1.5 IB Multiple Choice - Transcription](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/14-1-5-ib-multiple-choice-transcription.md) - 14.2 Water Potential - [14.2.1 Controlling Blood Water Potential](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/14-2-1-controlling-blood-water-potential.md) ### 15 Continuity & Change - Organisms - 15.1 Inheritance - [15.1.1 Non-Nuclear Inheritance](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/15-1-1-non-nuclear-inheritance.md) - [15.1.2 Linked Genes](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/15-1-2-linked-genes.md) - [15.1.3 IB Multiple Choice - Non-Mendelian Genetics](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/15-1-3-ib-multiple-choice-non-mendelian-genetics.md) - [15.1.4 Extended Response - Inheritance](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/15-1-4-extended-response-inheritance.md) - [15.1.5 Introduction to Non-Mendelian Inheritance](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/15-1-5-introduction-to-non-mendelian-inheritance.md) - [15.1.6 Chi-Squared Test](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/15-1-6-chi-squared-test.md) - [15.1.7 End of Topic Quiz - Inheritance](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/15-1-7-end-of-topic-quiz-inheritance.md) - [15.1.8 Sex-Linked Genes](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/15-1-8-sex-linked-genes.md) - [15.1.9 Grade 4-5 (Scientific Practices) - Inheritance](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/15-1-9-grade-4-5-scientific-practices-inheritance.md) - 15.2 Homeostasis - [15.2.1 Overview of Homeostasis](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/15-2-1-overview-of-homeostasis.md) - [15.2.2 Blood Glucose Concentration](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/15-2-2-blood-glucose-concentration.md) - [15.2.3 Controlling Blood Glucose Concentration](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/15-2-3-controlling-blood-glucose-concentration.md) - [15.2.4 End of Topic Test - Blood Glucose](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/15-2-4-end-of-topic-test-blood-glucose.md) - [15.2.5 Type I & Type II Diabetes](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/15-2-5-type-i-and-type-ii-diabetes.md) - [15.2.6 Human Reproductive Systems](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/15-2-6-human-reproductive-systems.md) - [15.2.7 Hormonal Control of the Menstrual Cycle](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/15-2-7-hormonal-control-of-the-menstrual-cycle.md) - [15.2.8 Kidneys & Osmoregulation](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/15-2-8-kidneys-and-osmoregulation.md) ### 16 Continuity & Change - Ecosystems - 16.1 Natural Selection - [16.1.1 Natural Selection](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/16-1-1-natural-selection.md) - 16.2 Stability & Change - [16.2.1 Coming Soon!](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/16-2-1-coming-soon.md) - 16.3 Climate Change - [16.3.1 Carbon Dioxide](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/16-3-1-carbon-dioxide.md) - [16.3.2 The Greenhouse Effect](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/16-3-2-the-greenhouse-effect.md) - [16.3.3 Global Warming](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/16-3-3-global-warming.md) - [16.3.4 Maintaining Biodiversity](https://senecalearning.com/en-gb/revision-notes/ib-diploma/biology/biology-ib-diploma/16-3-4-maintaining-biodiversity.md)