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To preserve systemic oxygen delivery during infection, the body raises heart rate to augment ____ while also recruiting stroke volume; over several hours, sympathetic tone and fluid shifts support this change, and peripheral tissues extract more oxygen when needed. Meanwhile, arterial oxygen content depends on the concentration of ____ and its saturation, summarized by C_aO21.34[Hb],S_aO2+0.003,P_aO2C\_{aO2} \approx 1.34\,[Hb]\\,S\_{aO2} + 0.003\\,P\_{aO2}, so improving ventilation and oxygenation can help sustain delivery. Because metabolic acid production can increase with fever and catabolism, hyperventilation lowers PaCO_2PaCO\_2 to defend arterial ____ as renal mechanisms catch up.

Course
Foundations of Human Biology
8 units36 lessons
Topics
BiologyHuman AnatomyHuman PhysiologyCell BiologyMolecular BiologyGenetics
About this course

This course builds a coherent framework for understanding human biology from molecules to organ systems. It develops scientific thinking and data literacy while covering cell structure and function, biomolecules, membranes and transport, enzymes and metabolism, and energy flow with ATP. It links tissues to organ-level physiology, emphasizing homeostasis, feedback, and core mechanisms in circulatory, respiratory, digestive, renal, nervous, endocrine, immune, musculoskeletal, integumentary, and reproductive systems, including gas exchange and circulation fundamentals. Foundations in Mendelian and molecular genetics, gene regulation and variation, and evolutionary principles are integrated with quantitative skills for rates, proportions, and graph interpretation.