Theoretical B Start Timed Attempt → 🏆 Leaderboard Theoretical B Exam Official Worked Solutions All Topics Biological Rhythms Calvin Cycle, Photorespiration & C4/CAM Biochemistry Cardiovascular Physiology Coevolution & Species Interactions Comparative Thermoregulation DNA Structure & Replication Ecology Endocrine System Physiology Enzyme Kinetics & Regulation Flower Anatomy & Reproductive Structures Gene Regulation: Eukaryotic & Epigenetics Genetic Drift, Gene Flow & Mutation Immune Physiology Molecular Evolution & Neutral Theory Muscle Physiology Nervous System Physiology Nucleotide & Nucleic Acid Chemistry Phylogenetic Trees & Cladistics Population Genetics & Hardy-Weinberg Equilibrium Quantitative Genetics, Heritability & Inbreeding Recombinant DNA & Biotechnology Techniques Respiratory Physiology Root Anatomy Translation & the Genetic Code Q1 Conus Snail Toxins and the Neuromuscular Junction Nervous System Physiology IBO·2015·Q1 — ptsPDF Q2 Hemoglobin Oxygen Affinity in Two Amazonian Fish Respiratory Physiology IBO·2015·Q2 — ptsPDF Q3 Training Effects on Lung Ventilation and Hyperventilation Respiratory Physiology IBO·2015·Q3 — ptsPDF Q4 Gut Hormones and Insulin Secretion After Gastric Bypass Endocrine System Physiology IBO·2015·Q4 — ptsPDF Q5 Hummingbird Physiology Across an Elevation Gradient Comparative Thermoregulation IBO·2015·Q5 — ptsPDF Q6 Reading Cardiac Cycle Information from an ECG Cardiovascular Physiology IBO·2015·Q6 — ptsPDF Q7 Testosterone, Pituitary Feedback, and Body Mass Endocrine System Physiology IBO·2015·Q7 — ptsPDF Q8 Oxygen Uptake and Lactate During and After Exercise Muscle Physiology IBO·2015·Q8 — ptsPDF Q9 Camel Fat Metabolism and Water Economy Comparative Thermoregulation IBO·2015·Q9 — ptsPDF Q10 Altitude Adaptation in Deer Mouse Hemoglobin Respiratory Physiology IBO·2015·Q10 — ptsPDF Q11 Glycemic Index and Metabolic Response During Exercise Muscle Physiology IBO·2015·Q11 — ptsPDF Q12 Phylogeny and Biogeography of Horseshoe Crabs Phylogenetic Trees & Cladistics IBO·2015·Q12 — ptsPDF Q13 Island Colonization History of Canary Islands Beetles Phylogenetic Trees & Cladistics IBO·2015·Q13 — ptsPDF Q14 Coevolution of Breeding and Pollination Systems in Figs Coevolution & Species Interactions IBO·2015·Q14 — ptsPDF Q15 The Pathogenic Life Cycle of Mycobacterium tuberculosis Immune Physiology IBO·2015·Q15 — ptsPDF Q16 Restriction Enzyme Strategies for Cloning a Gene Recombinant DNA & Biotechnology Techniques IBO·2015·Q16 — ptsPDF Q17 Mating-Type Switching in Budding Yeast Gene Regulation: Eukaryotic & Epigenetics IBO·2015·Q17 — ptsPDF Q18 Screening for Statin Resistance Genes in Yeast Enzyme Kinetics & Regulation IBO·2015·Q18 — ptsPDF Q19 Point Mutations, Frameshifts, and Codon Degeneracy Translation & the Genetic Code IBO·2015·Q19 — ptsPDF Q20 Genome Size and Base Composition in Horse-Family Hybrids Nucleotide & Nucleic Acid Chemistry IBO·2015·Q20 — ptsPDF Q21 A Bacterium-Nematode-Fungus Chemical Signaling Chain Ecology IBO·2015·Q21 — ptsPDF Q22 Stem Cell and Islet Co-transplantation for Diabetes Endocrine System Physiology IBO·2015·Q22 — ptsPDF Q23 Nuclear and Mitochondrial DNA Origin After Nuclear Transfer Recombinant DNA & Biotechnology Techniques IBO·2015·Q23 — ptsPDF Q24 Testing the Janzen-Connell Hypothesis with Pesticide Exclusion Ecology IBO·2015·Q24 — ptsPDF Q25 A Seabird-Mediated Nutrient Cascade on an Atoll Ecology IBO·2015·Q25 — ptsPDF Q26 Mercury Bioaccumulation Across the Marine Food Chain Ecology IBO·2015·Q26 — ptsPDF Q27 Large Herbivore Decline and Dung Beetle Fauna Since the Last Glacial Ecology IBO·2015·Q27 — ptsPDF Q28 Bumblebee-Flower Mismatch Under Climate Warming Coevolution & Species Interactions IBO·2015·Q28 — ptsPDF Q29 How a Burrowing Polychaete Alters Sediment Nitrogen Cycling Ecology IBO·2015·Q29 — ptsPDF Q30 Odour Receptors and Neuron Identity in C. elegans Nervous System Physiology IBO·2015·Q30 — ptsPDF Q31 Street Lighting and the Timing of Dawn Birdsong Biological Rhythms IBO·2015·Q31 — ptsPDF Q32 Gametophytic Self-Incompatibility Genetics in Clover Population Genetics & Hardy-Weinberg Equilibrium IBO·2015·Q32 — ptsPDF Q33 Genotype and Phenotype Frequencies at a Three-Allele Locus Population Genetics & Hardy-Weinberg Equilibrium IBO·2015·Q33 — ptsPDF Q34 Genotype-Dependent Outcomes of a Plant-Oomycete Interaction Coevolution & Species Interactions IBO·2015·Q34 — ptsPDF Q35 Hardy-Weinberg Expectations Across Generations of a Cross Population Genetics & Hardy-Weinberg Equilibrium IBO·2015·Q35 — ptsPDF Q36 Four Ways to Draw the Same Phylogeny Phylogenetic Trees & Cladistics IBO·2015·Q36 — ptsPDF Q37 Frog Phylogeny and Gondwanan Biogeography Phylogenetic Trees & Cladistics IBO·2015·Q37 — ptsPDF Q38 Salinity and Genetic Structure Among Baltic Fish Genetic Drift, Gene Flow & Mutation IBO·2015·Q38 — ptsPDF Q39 Coding vs Non-Coding Sequence Signatures in Cross-Species Alignments Molecular Evolution & Neutral Theory IBO·2015·Q39 — ptsPDF Q40 Rate and Fidelity of DNA Replication in Fast-Growing E. coli DNA Structure & Replication IBO·2015·Q40 — ptsPDF Q41 Backcrossing to Introgress a Disease-Resistance Allele Quantitative Genetics, Heritability & Inbreeding IBO·2015·Q41 — ptsPDF Q42 Day-Night Oxygen and Ethanol Cycling in Eelgrass Roots Root Anatomy IBO·2015·Q42 — ptsPDF Q43 CAM Photosynthesis and Carbon Limitation in an Aquatic Plant Calvin Cycle, Photorespiration & C4/CAM Biochemistry IBO·2015·Q43 — ptsPDF Q44 Pollen Donor Competition on the Stigma Flower Anatomy & Reproductive Structures IBO·2015·Q44 — ptsPDF Q45 Light and Depth Effects on Photosynthesis in a CAM Aquatic Plant Calvin Cycle, Photorespiration & C4/CAM Biochemistry IBO·2015·Q45 — ptsPDF Q46 The Mechanical Function of Buttress Roots Root Anatomy IBO·2015·Q46 — ptsPDF Q47 Nutrient Limitation of Baltic Phytoplankton Groups Ecology IBO·2015·Q47 — ptsPDF Q48 Reproductive Success in a Deceptively Pollinated Orchid Coevolution & Species Interactions IBO·2015·Q48 — ptsPDF Q49 Specialization and Phylogenetic Structure in a Bird-Plant Interaction Network Coevolution & Species Interactions IBO·2015·Q49 — ptsPDF