Which one of the following steps would be included in the primary response in humoral immunity?
a. antigen binds to antibodies
b. cytotoxic t cells bind to infected body cells and destroy them
c. t cells activate cytotoxic t cells
d. a macrophage consumes a virus and displays antigens on its surface and signals t cells to divide.

What re the two main phrases of the cell cycle.

Now it's your turn to investigate human impact around the world. grab your virtual lab coat and put on your environmental science hat. you will be taking a trip around the globe to explore three locations. at each location, you will investigate the cause and effect relationships of deforestation, desertification, and urbanization. you will also gather evidence of how these factors have impacted the environment over time

What happens when the cell copies its chromosomes