While the tadpoles of competing species may complete metamorphosis in as little as just a few short months, Bullfrog tadpoles can remain in the same state for as long as one to two years before they actually become adult frogs.
Two types of white blood cells called lymphocytes are vital to the specific immune response. Lymphocytes are produced in the bone marrow, and mature into one of several subtypes. The two most common are T cells and B cells. An antigen is a foreign material that triggers a response from T and B cells.
39) Which of the following are organs where activation of T and B cells usually occurs: A) bone marrow B) thymus C) lymph nodes D) lymph vessels E) all of the above Look here for the answer c.9) Which of the following cell types can be infected by HIV: A) B-cells B) T-helper cells C) macrophages D) glial cells E) all of the above Look here for the answer e. 50) Corticosteriods (such as prednisone) are commonly prescribed drugs for certain immune-related disorders.