Redirected from 722 BC
Decades: 770s BC 760s BC 750s BC 740s BC 730s BC - 720s BC - 710s BC 700s BC 690s BC 680s BC 670s BC
Significant People
... photosynthesis requires a source of hydrogen with which to reduce carbon dioxide into carbohydrates. Van Neil's proposal was confirmed 20 years later by using the O18 ...