Theoretical 2 Start Timed Attempt → 🏆 Leaderboard Theoretical 2 Exam + Official Answer Key & Solutions All Topics Bioenergetics & Central Metabolism Overview Biomolecular Analytical Techniques Calvin Cycle, Photorespiration & C4/CAM Biochemistry Cardiovascular Physiology Cell Junctions, Extracellular Matrix & Cell Death Cell Signaling & Communication Cell Theory, Prokaryotes & Eukaryotes Coevolution & Species Interactions Comparative Thermoregulation Cytoskeleton & Motor Proteins Endocrine System Physiology Enzyme Kinetics & Regulation Evidence for Evolution Extranuclear & Non-Mendelian Inheritance Flower Anatomy & Reproductive Structures Foraging & Anti-Predator Behavior Gene Interactions: Epistasis & Complementation Analysis Gene Regulation: Eukaryotic & Epigenetics History of Life: Origin & Major Transitions Human Evolution & Hominid Phylogeny Human Sensory Organs Immune Physiology Invertebrate Body Plans II Major Taxa Cross-Reference Mating Systems & Sexual Selection Mendel's Laws & Probability in Genetics Mineral Nutrition & Nutrient Uptake Mitochondria & Chloroplasts: Structure & Endosymbiotic Origin Molecular Evolution & Neutral Theory Natural Selection: Modes & Fitness Nervous System Physiology Nucleotide & Nucleic Acid Chemistry Pedigree Analysis & Human Genetic Disorders Phloem Transport & Translocation Plant Hormones Plant Stress Physiology & Defense Plasma Membrane Structure & Transport Quantitative Genetics, Heritability & Inbreeding Recombinant DNA & Biotechnology Techniques Respiratory Physiology Secondary Growth & Wood Anatomy Sex Determination & Sex-Linked Inheritance Speciation & Reproductive Isolation Transcription & RNA Processing Tropisms & Nastic Movements Water Transport & Transpiration All Easy Medium Hard Q1 Desert Bat Adaptations Comparative Thermoregulation Foraging & Anti-Predator BehaviorEasy IBO·2023·Q1 — ptsPDF Q2 Arabian Lizard Diversity Comparative Thermoregulation Major Taxa Cross-ReferenceMedium IBO·2023·Q2 — ptsPDF Q3 Shell Drilling Predation Invertebrate Body Plans II Foraging & Anti-Predator BehaviorMedium IBO·2023·Q3 — ptsPDF Q4 Whitefly Horizontal Gene Transfer Recombinant DNA & Biotechnology Techniques Coevolution & Species InteractionsMedium IBO·2023·Q4 — ptsPDF Q5 Angler Fish Immunity and Mating Immune Physiology Mating Systems & Sexual SelectionHard IBO·2023·Q5 — ptsPDF Q6 Missing Cell Types in Adults Cell Theory, Prokaryotes & EukaryotesEasy IBO·2023·Q6 — ptsPDF Q7 Elysia Kleptoplasty and Regeneration Mitochondria & Chloroplasts: Structure & Endosymbiotic OriginMedium IBO·2023·Q7 — ptsPDF Q8 Chromatin DNase Sensitivity Gene Regulation: Eukaryotic & Epigenetics Biomolecular Analytical TechniquesHard IBO·2023·Q8 — ptsPDF Q9 Microglia and Memory Forgetting Nervous System Physiology Immune PhysiologyMedium IBO·2023·Q9 — ptsPDF Q10 Cardiac Cell 14C Dating Cardiovascular PhysiologyMedium IBO·2023·Q10 — ptsPDF Q11 Kartagener Syndrome Cytoskeleton & Motor Proteins Respiratory PhysiologyMedium IBO·2023·Q11 — ptsPDF Q12 Visual Pathway Interruptions Nervous System Physiology Human Sensory OrgansMedium IBO·2023·Q12 — ptsPDF Q13 Lethal Temperature in Homeotherms Comparative ThermoregulationMedium IBO·2023·Q13 — ptsPDF Q14 Submarine Atmosphere and Oxygen Respiratory PhysiologyHard IBO·2023·Q14 — ptsPDF Q15 Ventilation and Respiratory Gas Control Respiratory PhysiologyHard IBO·2023·Q15 — ptsPDF Q16 Cell Surface-to-Volume Ratio Cell Theory, Prokaryotes & Eukaryotes Plasma Membrane Structure & TransportMedium IBO·2023·Q16 — ptsPDF Q17 Glucose Oxidase and Enzyme Kinetics Enzyme Kinetics & RegulationMedium IBO·2023·Q17 — ptsPDF Q18 Lactic Acid Fermentation Bioenergetics & Central Metabolism OverviewMedium IBO·2023·Q18 — ptsPDF Q19 cAMP Signaling and Caffeine Cell Signaling & CommunicationMedium IBO·2023·Q19 — ptsPDF Q20 Gasdermin and Pyroptosis Cell Junctions, Extracellular Matrix & Cell Death Immune PhysiologyHard IBO·2023·Q20 — ptsPDF Q21 Aconitase Mechanism Bioenergetics & Central Metabolism Overview Enzyme Kinetics & RegulationHard IBO·2023·Q21 — ptsPDF Q22 Metformin and Complex I Bioenergetics & Central Metabolism OverviewMedium IBO·2023·Q22 — ptsPDF Q23 Nerve Conduction and Volume Conductor Nervous System PhysiologyMedium IBO·2023·Q23 — ptsPDF Q24 C-STAR Blood Glucose Control Endocrine System Physiology Cell Signaling & CommunicationMedium IBO·2023·Q24 — ptsPDF Q25 Golden Gate Assembly Constructs Recombinant DNA & Biotechnology TechniquesHard IBO·2023·Q25 — ptsPDF Q26 T-DNA Southern Blot Analysis Recombinant DNA & Biotechnology Techniques Biomolecular Analytical TechniquesHard IBO·2023·Q26 — ptsPDF Q27 Gene Regulation by Protein Y Gene Regulation: Eukaryotic & EpigeneticsMedium IBO·2023·Q27 — ptsPDF Q28 Ancient DNA Extraction Biomolecular Analytical Techniques Nucleotide & Nucleic Acid ChemistryMedium IBO·2023·Q28 — ptsPDF Q29 Paulinella Chloroplast Endosymbiosis Mitochondria & Chloroplasts: Structure & Endosymbiotic Origin History of Life: Origin & Major TransitionsHard IBO·2023·Q29 — ptsPDF Q30 Parasite-Mediated Competition in Squirrels Coevolution & Species InteractionsMedium IBO·2023·Q30 — ptsPDF Q31 Cryptic Aricia Butterfly Species Speciation & Reproductive IsolationMedium IBO·2023·Q31 — ptsPDF Q32 Seabird Foraging and Niche Segregation Foraging & Anti-Predator BehaviorMedium IBO·2023·Q32 — ptsPDF Q33 Symbiodinium Nutrient Limitation Coevolution & Species InteractionsHard IBO·2023·Q33 — ptsPDF Q34 Bonnet Macaque Population Demography Natural Selection: Modes & FitnessMedium IBO·2023·Q34 — ptsPDF Q35 Primate Mating Systems Mating Systems & Sexual SelectionMedium IBO·2023·Q35 — ptsPDF Q36 Triceratops Skull Injuries Evidence for EvolutionMedium IBO·2023·Q36 — ptsPDF Q37 Group Selection Hypothesis Natural Selection: Modes & FitnessMedium IBO·2023·Q37 — ptsPDF Q38 Sex Ratio Evolution Natural Selection: Modes & Fitness Mating Systems & Sexual SelectionHard IBO·2023·Q38 — ptsPDF Q39 RNA Editing Mechanisms Transcription & RNA ProcessingMedium IBO·2023·Q39 — ptsPDF Q40 Drosophila Saturation Mutagenesis Recombinant DNA & Biotechnology TechniquesEasy IBO·2023·Q40 — ptsPDF Q41 RFLP Analysis of Cat Mucolipidosis Biomolecular Analytical Techniques Pedigree Analysis & Human Genetic DisordersHard IBO·2023·Q41 — ptsPDF Q42 Variant Call Format Genomics Recombinant DNA & Biotechnology TechniquesHard IBO·2023·Q42 — ptsPDF Q43 Twin Studies and Heritability Quantitative Genetics, Heritability & InbreedingMedium IBO·2023·Q43 — ptsPDF Q44 Gene Drive Technology Recombinant DNA & Biotechnology Techniques Sex Determination & Sex-Linked InheritanceHard IBO·2023·Q44 — ptsPDF Q45 Mustard Seed Coat Color Inheritance Gene Interactions: Epistasis & Complementation Analysis Extranuclear & Non-Mendelian InheritanceHard IBO·2023·Q45 — ptsPDF Q46 Mendelian Probability in Pea Pods Mendel's Laws & Probability in GeneticsHard IBO·2023·Q46 — ptsPDF Q47 Neanderthal Ancient DNA and Gene Flow Human Evolution & Hominid Phylogeny Molecular Evolution & Neutral TheoryHard IBO·2023·Q47 — ptsPDF Q48 Vascular Smooth Muscle and Atherosclerosis Cell Signaling & Communication Cardiovascular PhysiologyEasy IBO·2023·Q48 — ptsPDF Q49 Lacandonia Flower ABC Model Flower Anatomy & Reproductive StructuresMedium IBO·2023·Q49 — ptsPDF Q50 Phytochrome Thermosensing Plant Hormones Tropisms & Nastic MovementsHard IBO·2023·Q50 — ptsPDF Q51 C3 vs C4 Photosynthesis Calvin Cycle, Photorespiration & C4/CAM BiochemistryMedium IBO·2023·Q51 — ptsPDF Q52 Phloem Transport Under Water Stress Phloem Transport & Translocation Water Transport & TranspirationMedium IBO·2023·Q52 — ptsPDF Q53 Hydrogen Water and Banana Ripening Plant HormonesMedium IBO·2023·Q53 — ptsPDF Q54 Climate Change Effects on Rapeseed Oil Plant Stress Physiology & DefenseMedium IBO·2023·Q54 — ptsPDF Q55 Extrafloral Nectaries and Herbivory Defense Plant Stress Physiology & Defense Coevolution & Species InteractionsMedium IBO·2023·Q55 — ptsPDF Q56 Rubber Tree Stem Diameter Dynamics Water Transport & Transpiration Secondary Growth & Wood AnatomyMedium IBO·2023·Q56 — ptsPDF Q57 Root Hairs and Mycorrhizal Fungi Mineral Nutrition & Nutrient UptakeHard IBO·2023·Q57 — ptsPDF