Answer:
The Columbian exchanged fostered massive changes in both the Americas and Europe.
For the Americas, the first, and most radical change was the decimation of the Native American population, due to the spread of diseases of Eurasian origin, such as measles and syphillis, for which the Native Americans did not have any defenses. According to some historians, the spread of this diseases killed up to 95% of the pre-columbian Native American population.
The second change is related to the first, and was the immigration of many Europeans to the Americas: Spaniards to Spanish Latin America, Portuguese to Portuguese Latin America, and so on.
A third change came from the introduction of Eurasian goods: from horses, to cows, to apples, to rice and wheat. This changed the lifestyle and diet of even Native Americans. For example, Native Americans in the United States adapted to the use of horses, which became a crucial part of their culture.
