Anaerobic Respiration: Energy Without Oxygen
Part of Respiration — GCSE Biology
This deep dive covers Anaerobic Respiration: Energy Without Oxygen within Respiration for GCSE Biology. Topic 2: Respiration It is section 3 of 16 in this topic. Use this deep dive to connect the idea to the wider topic before moving on to questions and flashcards.
Topic position
Section 3 of 16
Practice
15 questions
Recall
20 flashcards
⚡ Anaerobic Respiration: Energy Without Oxygen
When oxygen supply is insufficient — for example, during an intense sprint — your cells switch to anaerobic respiration. This happens in the cytoplasm (not the mitochondria) and produces far less ATP per glucose molecule.
In Animals (Including Humans)
glucose → lactic acid
Lactic acid builds up in muscles, causing the burning sensation and fatigue during intense exercise. It is only a temporary solution — the body must deal with the lactic acid afterwards.
In Plants and Yeast (Fermentation)
glucose → ethanol + carbon dioxide
This process is used commercially in brewing (ethanol production) and bread-making (CO₂ makes dough rise). Note the critical difference: animal cells produce lactic acid, while yeast and plant cells produce ethanol and CO₂.