Photosynthetic Light Reactions
A leaf appears green because it reflects and transmits a larger fraction of green light than of much of the red and blue light it receives. That does not mean green light is unused. Some green light is absorbed and can drive photosynthesis, including in deeper leaf layers. Distinguish a lower absorp
Fermentation and NAD+ Recycling
During intense exercise, ATP demand rises rapidly and glycolysis can supply ATP at a high rate. Converting pyruvate to lactate regenerates the NAD \(^+\) needed to sustain that pathway. Oxygen limitation can increase reliance on this route, but lactate is also produced when oxygen is available. Neit
