Doctors trying to identify the nature of the immune response to a newly identified pathogen note that every time they isolate the antigen that the immune system is responding to, it is bound to the surface of a cell. This means that the component(s) of the immune system involved could be .

When do people generally experience rapid growth for a second time? a. between the ages of 3 and 9 b. between the ages of 9 and 12 c. between the ages of 13 and 20 d. between the ages of 25 and 29 which action occurs in the third stage of cell division? a. the nuclear material of cell is copied exactly. b. the nuclear membrane disappears. c. the cell forms two nuclei d. the nuclear material separates, with half moving to either side of the cell.