Final answer:
The main aspects of health examinations on Ellis Island were checking for infectious diseases and mental abnormalities, with contagious diseases like trachoma being a particular concern.
Step-by-step explanation:
The two main aspects of the health examinations performed on Ellis Island immigrants, as described in the excerpt from "Immigrant Kids" by Russell Freedman, were a) Checking for infectious diseases and mental abnormalities.
At Ellis Island, medical inspections were a crucial part of the immigration process, focusing primarily on identifying contagious diseases such as trachoma, which required a meticulous examination of the eyes by inverting the eyelids.
These health checks aimed to prevent the spread of such diseases within the country. In addition to medical examinations, there were also legal inspections which included asking questions about employment prospects and ensuring compliance with contract-labor laws, which could directly impact an immigrant's ability to remain in the United States.