Chapter 12

Allergies, or hypersensitivities, are normal immune responses.

FALSE

As people age, they become more resistant to the development of autoimmune and immunodeficiency diseases.

FALSE

Lymph nodes have more efferent vessels draining the node than afferent vessels bringing fluid into the node.

FALSE

The antibody a mother passes to her fetus is IgM.

FALSE

The most important function of the thymus gland is to destroy worn-out red blood cells and return some of the products to the liver.

FALSE

The study of immunity and the immune system is called endocrinology.

FALSE

There are three major immunoglobulin classes: IgM, IgA, and IgD.

FALSE

Vaccines provide naturally acquired active immunity to diseases such as pneumonia, diphtheria, and measles.

FALSE

Tissue grafts harvested from an unrelated person are called xenografts.

FALSE (allografts)

Natural killers are unique phagocytic defense cells that can kill cancer cells and virus-infected body cells well before the immune system is activated.

FALSE (limiting their spread and subsequent tissue damage.)

The final disposal of cell debris as inflammation subsides is performed by neutrophils.

FALSE (neutrophils start things)

The lymph nodes filter bacteria, viruses, and tumor cells from blood on its way back to the heart.

FALSE (production of lymphocytes, which help defend the body against microorganisms and against harmful foreign particles and debris from lymph before it is returned to the blood stream.)

Allografts are tissue grafts taken from an unrelated person.

True

Anaphylactic shock, an acute systemic allergic response, causes vasodilation and difficulty breathing.

True

Antibodies are also referred to as immunoglobulins

True

Antigen presentation is essential for the activation of clonal selection of T cells.

True

Artificially acquired passive immunity is conferred when one receives immune serum for poisonous snake bites.

True

Chemicals secreted by white blood cells and macrophages exposed to foreign substances that can increase body temperature are called pyrogens.

True

Injured cells release chemicals such as histamine and kinins that dilate vessels, attract phagocytes and activate pain receptors.

True

Like all blood cells, lymphocytes originate from hemocytoblasts contained within red bone marrow.

True

Lymph flows in one direction only: toward the heart.

True

Macrophages arise from monoctyes formed within the bone marrow.

True

Memory cells are descendants of an activated B or T cell.

True

The lymphatic vessels and cardiovascular veins are similar in that they operate under low pressure and some larger ones have valves.

True

The nonspecific defense by which complement proteins attach to sugars or proteins on the surface of foreign cells is called complement fixation.

True

The process that occurs when antibodies clump foreign cells is called agglutination.

True