Theoretical A

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Mixed format (multiple-choice, true/false, numeric, and a few short-answer questions) - short-answer questions are shown for you to check against the model answer but aren't scored in the timed attempt.

Theoretical A Exam Official Answer Key (Practicals + Theoretical Exams)

Q1 C. elegans Apoptosis Gene Network Cell Junctions, Extracellular Matrix & Cell Death IBO·2019·Q1 — ptsPDF

Q2 CLK Mutation and Circadian PER Oscillations Biological Rhythms IBO·2019·Q2 — ptsPDF

Q3 GPCR Signalling and a Toxin Acting on the Gs Cycle Cell Signaling & Communication IBO·2019·Q3 — ptsPDF

Q4 CDK Knockout and Liver Regeneration Cell Cycle, Mitosis & Meiosis IBO·2019·Q4 — ptsPDF

Q5 UCP Family and Non-Shivering Thermogenesis Comparative Thermoregulation IBO·2019·Q5 — ptsPDF

Q6 A Two-Polypeptide Gene with an Intron DNA Structure & Replication IBO·2019·Q6 — ptsPDF

Q7 Thermus szegediensis, Nutrition and Complementation Cell Theory, Prokaryotes & Eukaryotes IBO·2019·Q7 — ptsPDF

Q8 Beadle & Tatum, One Gene, One Enzyme Mendel's Laws & Probability in Genetics IBO·2019·Q8 — ptsPDF

Q9 Bulb1/Bulb2 and the UV-B Response in Arabidopsis Photoperiodism, Vernalization & Flowering IBO·2019·Q9 — ptsPDF

Q10 Pressure and Volume Changes During Breathing Respiratory Physiology IBO·2019·Q10 — ptsPDF

Q11 Acid-Base Balance, Reading a Blood Gas Map Homeostasis & Osmoregulation IBO·2019·Q11 — ptsPDF

Q12 Antibiotic Pharmacokinetics in a Cow Digestive & Metabolic Physiology IBO·2019·Q12 — ptsPDF

Q13 Renal Handling of Glucose Human Excretory System IBO·2019·Q13 — ptsPDF

Q14 Liver, Gallbladder, and Kidney Vessels Human Excretory System IBO·2019·Q14 — ptsPDF

Q15 Classifying Hypersensitivity Reactions Immune Physiology IBO·2019·Q15 — ptsPDF

Q16 Cochlear Frequency Coding and Sound Pressure Human Sensory Organs IBO·2019·Q16 — ptsPDF

Q17 Feeding Time and the Central vs. Peripheral Circadian Clock Biological Rhythms IBO·2019·Q17 — ptsPDF

Q18 The Thyroid Axis in Five Clinical Scenarios Endocrine System Physiology IBO·2019·Q18 — ptsPDF

Q19 Thyroid Hormone, Oxidative Stress, and the Heart Endocrine System Physiology IBO·2019·Q19 — ptsPDF

Q20 GNC/GLK Transcription Factors and Chloroplast Development Gene Regulation: Eukaryotic & Epigenetics IBO·2019·Q20 — ptsPDF

Q21 Drought Effects on Olive Leaf Anatomy Plant Stress Physiology & Defense IBO·2019·Q21 — ptsPDF

Q22 What Limits the Height of the Tallest Trees? Water Transport & Transpiration IBO·2019·Q22 — ptsPDF

Q23 Statoliths and Root Geotropism in Microgravity Tropisms & Nastic Movements IBO·2019·Q23 — ptsPDF

Q24 Nitric Oxide and Guard Cell K+ Currents Stomatal Physiology & Gas Exchange IBO·2019·Q24 — ptsPDF

Q25 The Luria-Delbrück Replica Plating Experiment Genetic Drift, Gene Flow & Mutation IBO·2019·Q25 — ptsPDF

Q26 Inheritance of Sterility in a Pedigree Pedigree Analysis & Human Genetic Disorders IBO·2019·Q26 — ptsPDF

Q27 Baldness, Rh Factor, and Genetic Counselling Linkage, Recombination & Genetic Mapping IBO·2019·Q27 — ptsPDF

Q28 How Long Until a Random Sequence Repeats in the Genome? Nucleotide & Nucleic Acid Chemistry IBO·2019·Q28 — ptsPDF

Q29 Reverse-Engineering a Peptide-Shortening Mutation Translation & the Genetic Code IBO·2019·Q29 — ptsPDF

Q30 An X-Linked, Epigenetically-Acting Eye-Colour Gene Mendel's Laws & Probability in Genetics IBO·2019·Q30 — ptsPDF

Q31 Smallmouth Bass Removal and Population Structure Ecology IBO·2019·Q31 — ptsPDF

Q32 The SIR Model of Parasite Population Dynamics Ecology IBO·2019·Q32 — ptsPDF

Q33 Tracing Indirect Effects Through a Food Web Ecology IBO·2019·Q33 — ptsPDF

Q34 Assembling a Bird Phylogenetic Tree from Fragments Phylogenetic Trees & Cladistics IBO·2019·Q34 — ptsPDF

Q35 A New Gall Wasp Genus, Molecular Systematics Molecular Systematics IBO·2019·Q35 — ptsPDF

Q36 Reconciling Two Independent Legume Phylogenies Phylogenetic Trees & Cladistics IBO·2019·Q36 — ptsPDF

Q37 Why Bats Collide With Smooth Surfaces Animal Communication IBO·2019·Q37 — ptsPDF

Q38 Attractant vs. Repellent Pheromones in Pharaoh Ants Animal Communication IBO·2019·Q38 — ptsPDF