Which of the following statements is true of the immune system?
A) Its machinery consists of billions of red blood cells.
B) When a person is under stress, the levels of bacteria and viruses drop dramatically.
C) Lower levels of natural killer (NK) cells in stressful situations indicate a weakened immune system.
D) Stress increases the number of natural killer (NK) cells in the body.

Question

Quizplus · Accepted Answer

Lower levels of natural killer (NK) cells in stressful situations indicate a weakened immune system. This is because NK cells are a type of white blood cell that play an important role in detecting and destroying virus-infected cells and cancer cells. When NK cell levels are low, the immune system is less able to fight off these types of infections and diseases.

Which of the Following Statements Is True of the Immune