Sub-topic 1
2026 · National One-Eighth
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The heart: structure and function
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Sub-topic 2
2024 · National Preliminary
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The heart: structure and function
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Sub-topic 3
2024 · National Preliminary
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Blood vessels in humans: arteries, veins and their functions
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Sub-topic 4
2024 · National Preliminary
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Circulatory system physiology: blood flow, pressure and regulation
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Sub-topic 5
2026 · National Preliminary
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Number of heart chambers across groups of organisms
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Sub-topic 6
2026 · National Preliminary
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Number of heart chambers across groups of organisms
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Sub-topic 7
2026 · National Semifinal
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Hematopoietic stem cells as the source of red and white blood cells
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Sub-topic 8
2026 · National Semifinal
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Afterload: the resistance the heart overcomes to pump blood
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Sub-topic 9
2026 · National Quarterfinal
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Systole: the contraction phase of the cardiac cycle
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Sub-topic 10
2026 · National Quarterfinal
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Homeostasis: stable blood salt concentration despite varying dietary intake
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Sub-topic 11
2026 · National Quarterfinal
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Interstitial (tissue) fluid: the fluid bathing body cells other than blood cells
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Sub-topic 12
2026 · National One-Eighth
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Heart structure: septum preventing mixing of blood
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Sub-topic 13
2026 · National One-Eighth
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Blood composition: serum versus plasma
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Sub-topic 14
2021 · National One-Eighth
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Fish heart structure: the sinus venosus
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Sub-topic 15
2021 · National Preliminary
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Distinguishing blood plasma from serum
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Sub-topic 16
2026 · National One-Eighth
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Distinguishing blood plasma from serum
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Sub-topic 17
2026 · National Preliminary
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Blood groups and the absence of red cell surface antigens
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Sub-topic 18
2025 · National Final
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Rh-null blood as the blood type lacking all antigens
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Sub-topic 19
2025 · Regional Championship
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How specific structures of the human heart contribute to the heartbeat
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Sub-topic 20
2025 · Regional Championship
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How specific structures of the human heart contribute to the heartbeat
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Sub-topic 21
2026 · National Preliminary
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Which blood components exhibit amoeboid movement (true/false)
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Sub-topic 22
2024 · National Preliminary
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Components of the human cardiovascular system: heart, blood vessels and blood
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Sub-topic 23
2024 · National Preliminary
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The red color of blood: oxidation state of iron in hemoglobin
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Sub-topic 24
2013 · National Quarterfinal
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Why some water molecules cannot move freely across the plasma membrane
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Sub-topic 25
2017 · National Semifinal
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Oxygen delivery to muscle via red blood cells and the circulatory system
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Sub-topic 26
2017 · National Semifinal
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Sequence of cardiac valve events during heart contraction
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Sub-topic 27
2021 · National Preliminary
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Left ventricle has the thickest wall, pumping blood to the whole body
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Sub-topic 28
2021 · National Quarterfinal
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Blood from the jejunum and ileum drains via the hepatic portal vein
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Sub-topic 29
2021 · National Quarterfinal
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Blood passes into the right ventricle after crossing the tricuspid valve
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