What were the two most important items exchanged that came from the Old World to the New World? Why were they so important?

To begin, please watch (or rewatch) the Crash Course video on the Columbian Exchange, which is included below, and read The Columbian Exchange. This will provide you with an overview of the exchange and its influence. When you are ready to post, please respond to all four of the following questions about the Columbian Exchange:

What were the two most important items exchanged that came from the Old World to the New World? Why were they so important?
What were the two most important items exchanged that came from the New World to the Old World? Why were they so important?
What was the most significant problem caused or liability introduced in the Old World and in the New World by the Columbian Exchange? Explain.
In your opinion, was the overall impact of the Columbian Exchange positive or negative? In other words, would the earth have been better off without this exchange? As you discuss your perspective, explain both the major positive and negative effects that guide your opinion.

Last Completed Projects