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Theoretical B

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Theoretical B Exam Official Answer Key & Worked Solutions
Q1 Enzyme-Limited Carbon Fixation in a Warming Amazon Calvin Cycle, Photorespiration & C4/CAM Biochemistry Ecology IBO·2017·Q1 — ptsPDF
Q2 Ocean Acidification and Deep-Sea Chemosynthesis Ecology Bioenergetics & Central Metabolism Overview IBO·2017·Q2 — ptsPDF
Q3 Reading Lung and Kidney Disease from Blood Gas Values Respiratory Physiology IBO·2017·Q3 — ptsPDF
Q4 Carbon Monoxide's Real Effect on Oxygen Transport Respiratory Physiology IBO·2017·Q4 — ptsPDF
Q5 CO2, Not O2, Drives Everyday Breathing Rate Respiratory Physiology IBO·2017·Q5 — ptsPDF
Q6 Comparing Gas Exchange Strategies Across Animal Groups Comparative Respiration & Circulation IBO·2017·Q6 — ptsPDF
Q7 Tidal Pressure Changes Drive Mangrove Root Gas Exchange Stomatal Physiology & Gas Exchange IBO·2017·Q7 — ptsPDF
Q8 Temperature and Metabolism Set Oxygen Levels in a Seagrass Meristem Stomatal Physiology & Gas Exchange IBO·2017·Q8 — ptsPDF
Q9 Counting Electrons Through the Oxygen-Evolving Complex Light Reactions & Photophosphorylation IBO·2017·Q9 — ptsPDF
Q10 Why the Heart Can't Suck Blood: The Frank-Starling Mechanism Cardiovascular Physiology IBO·2017·Q10 — ptsPDF
Q11 Diagnosing Heart Disease from Pressure-Volume Loops Cardiovascular Physiology IBO·2017·Q11 — ptsPDF
Q12 Osmolarity, Not Volume, Dominates Fast Kidney Responses Homeostasis & Osmoregulation IBO·2017·Q12 — ptsPDF
Q13 Glomerulus Size and Habitat Shape Kidney Concentrating Power Comparative Osmoregulation & Excretion IBO·2017·Q13 — ptsPDF
Q14 Using Inulin Clearance to Measure Kidney Filtration Homeostasis & Osmoregulation IBO·2017·Q14 — ptsPDF
Q15 Competition and Salt Tolerance Divide Two Marsh Plants Plant Stress Physiology & Defense Ecology IBO·2017·Q15 — ptsPDF
Q16 Antifreeze Proteins and Membrane Chemistry in Polar Fish Comparative Thermoregulation Lipids & Membrane Biochemistry IBO·2017·Q16 — ptsPDF
Q17 Genome Streamlining Tracks Niche Specialisation in Marine Cyanobacteria Molecular Evolution & Neutral Theory Ecology IBO·2017·Q17 — ptsPDF
Q18 Surface-to-Volume Scaling Explains Animal Body Proportions Locomotion & Energetics IBO·2017·Q18 — ptsPDF
Q19 Fibre-Type Composition Explains a Human-Chimp Muscle Trade-off Muscle Physiology IBO·2017·Q19 — ptsPDF
Q20 A Revised Dinosaur Phylogeny Overturns Assumptions About Traits Phylogenetic Trees & Cladistics IBO·2017·Q20 — ptsPDF
Q21 Gut Anatomy Tracks Diet Across Apes, Dogs, and Pandas Digestive & Metabolic Physiology IBO·2017·Q21 — ptsPDF
Q22 Ancient DNA Reveals the Beaker People Replaced, Not Joined, Britain Human Evolution & Hominid Phylogeny Population Genetics & Hardy-Weinberg Equilibrium IBO·2017·Q22 — ptsPDF
Q23 Temperature-Dependent Sex Determination in Two Turtle Populations Reproductive Physiology Ecology IBO·2017·Q23 — ptsPDF
Q24 Reading Cell Identity and Function from Testis Ultrastructure Reproductive Physiology IBO·2017·Q24 — ptsPDF
Q25 Do ABC Transporters Pump Floral Scent Out of Petal Cells? Plasma Membrane Structure & Transport IBO·2017·Q25 — ptsPDF
Q26 Homeotic Genes Define Flower and Body Segment Identity Flower Anatomy & Reproductive Structures Evolutionary Developmental Biology (Evo-Devo) IBO·2017·Q26 — ptsPDF
Q27 Fruitless Isoforms Separate Appearance from Sexual Orientation Mechanisms of Behavior IBO·2017·Q27 — ptsPDF
Q28 Cytoplasmic Reprogramming and the Persistence of Cell Identity Gene Regulation: Eukaryotic & Epigenetics IBO·2017·Q28 — ptsPDF
Q29 Random Sorting of Chloroplasts in a Variegated Plant Extranuclear & Non-Mendelian Inheritance IBO·2017·Q29 — ptsPDF
Q30 Heteroplasmy Thresholds Behind Mitochondrial Replacement Therapy Mitochondria & Chloroplasts: Structure & Endosymbiotic Origin Extranuclear & Non-Mendelian Inheritance IBO·2017·Q30 — ptsPDF
Q31 Grafting Reveals Barriers to Gene and Genome Transfer Between Species Extranuclear & Non-Mendelian Inheritance Speciation & Reproductive Isolation IBO·2017·Q31 — ptsPDF
Q32 Human Embryos Break the Established OCT4/GATA6 Rulebook Cell Signaling & Communication Evolutionary Developmental Biology (Evo-Devo) IBO·2017·Q32 — ptsPDF
Q33 Which Developmental Unit Was Selected to Make Each Brassica Crop? Plant Body Plans Across Major Lineages IBO·2017·Q33 — ptsPDF
Q34 p53's Tetramer Threshold Guards Against Cancer Cell Cycle, Mitosis & Meiosis IBO·2017·Q34 — ptsPDF
Q35 "Seed and Soil": Why Tumours Favour Specific Secondary Organs Cell Junctions, Extracellular Matrix & Cell Death Natural Selection: Modes & Fitness IBO·2017·Q35 — ptsPDF
Q36 A Luciferase Reporter Measures Caspase Activity in Apoptosis Cell Junctions, Extracellular Matrix & Cell Death IBO·2017·Q36 — ptsPDF
Q37 Rerouting Flux Through an Engineered Krebs Cycle for Lysine Bioenergetics & Central Metabolism Overview IBO·2017·Q37 — ptsPDF
Q38 Diagnosing Electron Transport Chain Poisons from O2 Traces Bioenergetics & Central Metabolism Overview IBO·2017·Q38 — ptsPDF
Q39 Phosphocreatine and Glycolysis Power the 100m Sprint Locomotion & Energetics Bioenergetics & Central Metabolism Overview IBO·2017·Q39 — ptsPDF
Q40 Mendelian Randomisation Separates Correlation from Causation Population Genetics & Hardy-Weinberg Equilibrium IBO·2017·Q40 — ptsPDF
Q41 Antibody Evolution Traces the Red Queen Dynamic in Untreated HIV Molecular Evolution & Neutral Theory Immune Physiology IBO·2017·Q41 — ptsPDF
Q42 Extracellular vs Intracellular Resistance Enzymes Shape Selection Pressure Natural Selection: Modes & Fitness IBO·2017·Q42 — ptsPDF
Q43 Self-Templating Misfolding Drives Prion Disease Dynamics Protein Structure, Folding & Function IBO·2017·Q43 — ptsPDF
Q44 Comparing Two Active-Site Inhibitors for a Tuberculosis Target Enzyme Kinetics & Regulation IBO·2017·Q44 — ptsPDF
Q45 Cross-Immunity and Persistence Explain Smallpox's Eradication over Cholera's Immune Physiology IBO·2017·Q45 — ptsPDF
Q46 Tracing a De Novo Haemophilia Mutation Through European Royalty Pedigree Analysis & Human Genetic Disorders Sex Determination & Sex-Linked Inheritance IBO·2017·Q46 — ptsPDF