【单选题】A researcher discovered that people who have low levels of immune-system activity tend to score much lower on tests of mental health than do people with normal or high immune-system activity. The rese...
A.
High immune-system activity protects against mental illness better than normal immune-system activity does.
B.
Mental illness is similar to physical disease in its effects on body system.
C.
People with high immune-system activity cannot develop mental illness.
D.
Mental illness does not cause people's immune-system activity to decrease.
E.
Psychological treatment of mental illness is not as effective as is medical treatment.
【单选题】Which of the following statements about the immune system is wrong?
A.
Immunity is brought about by a variety of leukocytes (white blood cells), including macrophages and lymphocytes, all of which develop from undifferentiated stem cells in the bone marrow.
B.
The immune response consists of two complementary systems, the humoral and cellular immune systems. The humoral immune system is directed at bacterial infections and extracellular viruses (those found in the body fluids), but can also respond to individual foreign proteins. The cellular immune system destroys host cells infected by viruses and also destroys some parasites and foreign tissues.
C.
Immunoglobulins bind bacteria, viruses, or large molecules identified as foreign and target them for destruction. Making up 20% of blood protein, the immunoglobulins are produced by B lymphocytes, or B cells, so named because they complete their development in the brain.
D.
Recognition of infected cells or parasites involves proteins called T-cell receptors on the surface of cytotoxic T cells.