Income Level in the United States Is Directly Correlated with

question 47

Multiple Choice

Income level in the United States is directly correlated with

• A) geographic location of the home relative to a major city.
• B) level of education of the primary wage earner.
• C) number of family members in the home.
• D) none of these.

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Definitions:

Humoral Immunity

One of the three general categories of immune response, in which invading antigens are presented by macrophages to B-lymphocytes. (“B” stands for bursa, an organ in which such cells are produced in birds. B-lymphocytes derive from the liver and bone marrow in humans.) This causes the B-cells to reproduce—a process reinforced by the lymphokine secretion from the helper T-cells. Some of the activated B-cells remain as memory B-cells. Others go on to be plasma cells, secreting antibodies called immunoglobulins that neutralize antigens in a number of different ways, such as clumping, presenting the antigen to phagocytic cells, or rupturing the antigen.

Macrophages

A type of white blood cell that engulfs and digests cellular debris, foreign substances, microbes, and cancer cells in a process called phagocytosis.

Memory B-Cells

A type of white blood cell involved in the immune response, capable of remembering past infections and pathogens to produce a quicker response upon re-exposure.

B-Lymphocytes

A type of white blood cell that plays a crucial role in the immune system by producing antibodies, which help fight off infections and diseases.