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BiologyAQA (7402) / Edexcel (9BN0)Energy & Ecosystems

Photosynthesis & Respiration Interactive Guide

AQA / Edexcel A-Level Biology

Photosynthesis and respiration are two of the most heavily examined topics in A-Level Biology. This interactive guide lets you explore each stage in detail — the light-dependent reactions and Calvin cycle for photosynthesis, and glycolysis, the link reaction, Krebs cycle, and oxidative phosphorylation for respiration. Toggle between processes, follow the flow of carbon, hydrogen, and energy carriers (ATP, NADH, FADH2), and build the conceptual understanding needed for 25-mark synoptic essays.

Uses Google Fonts (Playfair Display, Source Sans 3). Requires an internet connection for full styling.

Frequently asked questions

What are the main stages of aerobic respiration?+
Aerobic respiration has four stages: glycolysis (cytoplasm), the link reaction (mitochondrial matrix), the Krebs cycle (mitochondrial matrix), and oxidative phosphorylation (inner mitochondrial membrane). The overall equation is C6H12O6 + 6O2 → 6CO2 + 6H2O + ATP.
Where do the light-dependent reactions of photosynthesis take place?+
The light-dependent reactions take place on the thylakoid membranes of chloroplasts. Light energy is absorbed by chlorophyll, water is photolysed, and ATP and reduced NADP are produced for use in the Calvin cycle.

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