Redirected from 638 BC
Decades: 680s BC 670s BC 660s BC 650s BC 640s BC - 630s BC - 620s BC 610s BC 600s BC 590s BC 580s BC
Significant People
... is similar to the Krebs cycle in some regards. Carbon enters the Calvin cycle in the form of CO2 and leaves in the form of a carbohydrate such as sugar, with the reaction ...