Answer to Question 1
The transcontinental railroad increased the pace of westward immigration in the United States by establishing links between culture hearths and settlements along its path. Railroad companies, in partnership with immigration bureaus, aggressively recruited settlers at county fairs, churches, and other social gatherings to move out west and fill land provided by the Homestead Act. Many of these settlers, after moving to the West, were then dependent on the railroad companies to move their agricultural product to market. Likewise, the interstate highway system, built in the 1950s, provided a transportation route that greatly reduced travel time for people, which allowed them to live away from the previous main transportation corridors, and for products moving to and from outlying regions.
Answer to Question 2
Some of the answers the student should mention are resource conflicts for primary resources such as furs, fish, and the control of territory. The 1763 Treaty of Paris, which gave the land north of Massachusetts up to Acadia to Great Britain, did not set exact boundaries, and so this caused tension between France and Britain along the borders, and forced the removal of French Acadians by the British. This subject is covered in greater detail in Chapter 6: Quebec.
The tracheal system of insects.
The accessory organs of the digestive system: the liver, gallbladder, and pancreas. Image shows the
Central Nervous System Stimulants That Are Scheduled Drugs
Production-scale tangential flow filtration system.
Landsteiner's experiment demonstrating the exquisite specificity of the immune system.
The Excretory System Water and waste products from cells