Grapevine physiology: How does a grapevine make sugar?

First two sentences: All forms of viticultural produce(grapes, raisins, distilled wine alcohol) have their origins in the sugars produced within grapevine leaves by a process known as photosynthesis. When leaves photosynthesize they use energy from the sun to manufacture sugar from carbon dioxide (CO2) absorbed from the air and water drawn from the soil.