Cambridge IGCSE Biology (0610) - IGCSE Biology - Respiration (12.1)

🎓 IGCSE Biology - The Complete Course: https://www.tes.com/teaching-resource/resource-12989155 IGCSE Chemistry - The Complete Course: 🎓 Complete Teaching Resource (including past exam questions and mark schemes organised by chapter): https://www.tes.com/teaching-resource/resource-13280954 🎓 Student resource (PDF only): https://www.tes.com/teaching-resource/resource-13245244 🎓 All the videos (the complete library on Patreon): https://www.patreon.com/igbiocomplete ☕️ Buy me a coffee - https://www.buymeacoffee.com/ArthurJohnParker Cambridge IGCSE Biology (0610/0970) Chapter 12 - Respiration Topic 12.1 - Respiration For exams from 2025 (core and extended) As always this video follows the Cambridge syllabus exactly and contains absolutely everything you need to know for your final exam! My other channels: @igpecomplete - Cambridge IGCSE PE @ocrpecomplete - OCR GCSE PE Timestamps: 0:00 Contents 0:25 Respiration 0:44 Energy consuming processes 1:24 Respiration in yeast Core content: - State the uses of energy in living organisms, including: muscle contraction, protein synthesis, cell division, active transport, growth, the passage of nerve impulses and the maintenance of a constant body temperature. - Investigate and describe the effect of temperature on respiration in yeast. There's no extended content for this lesson. Context: - In our next lesson we'll learn about aerobic and anaerobic respiration, including the word equations and balanced chemical equations. - Aerobic respiration is the chemical reactions in cells that use oxygen to break down nutrient molecules to release energy. Glucose and oxygen undergo a series of reactions (mediated by enzymes), to release the byproducts carbon dioxide, water and usable energy or ATP. - Anaerobic respiration is the chemical reactions in cells that break down nutrient molecules to release energy without using oxygen. - Yeast cells convert glucose to alcohol (ethanol) and carbon dioxide. - Muscle cells respire anaerobically during vigorous (high intensity) exercise. Glucose is converted to lactic acid, which accumulates causing discomfort and muscle fatigue. - The lactic acid is transported in the bloodstream and broken down in the liver by deamination, forming urea. - The urea is subsequently filtered out of the blood and excreted by the kidneys. - Lactic acid creates an oxygen debt, which is paid off after physical activity. Heart rate, stroke volume and cardiac output, as well as breathing rate and depth (tidal volume) remain elevated for some time. - This provides the oxygen needed to break down the lactic acid.