White blood cells engulf invaders or produce antibodies that attack
them or mark them for killing by other white cells. The antibodies produced
will remain and can fight off subsequent invaders of the same kind.
| NSES Content Standard C
Life Science: Structure and function in living systems Grades 5-8, page 156 The human organism has systems for digestion, respiration, reproduction, circulation, excretion, movement, control and coordination, and for protection from disease. These systems interact with one another. |