Helper T cells are very important cells in the adaptive immunity. They are required for almost all adaptive immune responses and They also help activate cytotoxic T cells and macrophages to attack infected cells.
I hope this helped, Good Luck!!
Answer:
a scar is a environmental change
Presidential Reconstruction
In the spring of 1865, the Civil War came to an end, leaving over 620,000 dead and a devastating path of destruction throughout the south. The North now faced the task of reconstructing the ravaged and indignant Confederate states. There were many important questions that needed to be answered as the nation faced the challenges of peace:
<span>Who would direct the process of Reconstruction? The South itself, Congress, or the President?Should the Confederate leaders be tried for treason?How would the south, both physically and economically devastated, be rebuilt? And at whose expense?How would the south be readmitted and reintegrated into the Union?<span>What should be done with over four million freed slaves? Were they to be given land, social equality, education, and voting rights?</span></span>