A&P 2 Chapter 21 Concepts

A typical adult has about how many lymph nodes?

450

Which areas of an antibody determine specificity?

A

What are possible causes for a lack of self tolerance?

Abnormal exposure to self antigens Alteration of self antigens Cross reactivity between similar antigens

Which lymphatic vessels carry lymph into a lymph node?

Afferent

What are mucosal associated lymphatic tissues?

Aggregates of lymphatic tissue scattered throughout the lamina propria of mucous membranes

A patient who is immunodeficient would have which of the following?

An underactive immune system

What is any large molecule capable of triggering an immune response called?

Antigen

Which cell phagocytizes an antigen and displays fragments of it on its surface?

Antigen-presenting cell

Interferons, complement, defensins and granzymes are examples of which of the following?

Antimicrobial proteins

______ diseases result from failures of self-tolerance.

Autoimmune

Humoral immunity is mediated by ______ lymphocytes.

B

What are three antimicrobial proteins?

Complement Interferon Defensin

Which T cells attack and destroy target cells by secreting perforins and granzymes?

Cytotoxic

Which cells induce cytolysis by secreting perforin?

Cytotoxic T cells NK cells

What does the first line of defense against pathogens consist of?

External barriers

True or false: Both lymphatic tissues and lymphatic organs have distinct connective tissue capsules surrounding them.

False

True or false: Lymphatic capillaries are open-ended vessels consisting of loosely overlapping endothelial cells.

False

What are functions of lymph nodes?

Filtration of lymph Site of B and T cell activation

What are three functions of the lymphatic system?

Fluid recovery from tissues Immunity Absorption of lipids

NK cells induce apoptosis in virally infected cells by secreting which protein-degrading enzymes?

Granzymes

Which type of immunity is mediated by B cells and the antibodies they secrete?

Humoral

Where is body temperature regulated?

Hypothalamus

MHC class ______ proteins occur on all nucleated somatic cells and may trigger a cytotoxic T cell response if displaying a viral protein.

I

Which are characteristics of a primary immune response?

IgM antibodies are formed first. It occurs with the first exposure to an antigen. Antibodies first appear 3-6 days after exposure, peaking at day 10.

Redness, heat, swelling, and pain are signs that accompany which process?

Inflammation

A T cell will only become activated if what occurs? Select all that apply.

It is costimulated by other surface molecules. It binds to a foreign antigen presented on an MHC protein.

Which are characteristics of a secondary immune response?

It occurs after the second and subsequent exposures to an antigen. IgG antibodies are formed first. Antibodies first appear within hours, peaking at day 3.

Distinct connective tissue capsules surround which of the following?

Lymphatic organs

Which body system maintains fluid balance, absorbs lipids, and protects the body against pathogens?

Lymphatic system

Once a B cell binds an antigen, it phagocytizes it and displays antigen fragments on what molecules?

MHC-II proteins

What does MALT stand for?

Mucosa-associated lymphatic tissue

Which describes a neutrophil?

Multi-lobed nucleus with cytoplasmic granules

Antibodies function to render antigens harmless by which of the following?

Neutralization Complement fixation Agglutination Precipitation

Which leukocyte destroys bacteria by means of phagocytosis, intracellular digestion, and the secretion of bactericidal chemicals?

Neutrophil

______ are granulocytes with a multi-lobed nucleus that destroy bacteria by means of phagocytosis, intracellular digestion, and secretion of bactericidal chemicals.

Neutrophils

Where are type I MHC proteins found?

On all nucleated body cells

Which primary lymphoid organ is the site of B cell maturation?

Red bone marrow

Which characteristic describes how immunity is directed against a particular pathogen, and that immunity to one pathogen usually does not confer immunity to others?

Specificity

Which class of lymphocyte matures in the thymus?

T cells

Cellular immunity is mediated mainly by ______ cells, while humoral immunity is mediated mainly by ______ cells.

T, B

Why do memory T cells allow for a faster immune response when the body is exposed to the same antigen again?

There are more of them. There are fewer steps to activation.

Which describe allergens.

They are environmental antigens. They can occur in mold, dust, and pollen. They induce allergies.

Where do T cells mature?

Thymus

Which are primary lymphatic organs?

Thymus Red bone marrow

What are the immunological benefits of inflammation?

To initiate tissue repair To limit the spread of pathogens To remove the debris of damaged tissue

Cytotoxic T cells attack and destroy target cells by secreting which of the following?

Tumor necrosis factor Granzymes Interferons Perforins

What is required for activation of a B cell?

Usually, it must bind a helper T cell. It must bind an antigen on several surface receptors.

Lymphatic vessels are anatomically very similar to which of the following?

Veins

Which bone marrow is mainly adipose tissue?

Yellow

Antigens which induce hypersensitivity responses are called .

allergens

Molecules that function to render antigens harmless by neutralization, complement fixation, agglutination and precipitation are called ______.

antibodies

Cells that phagocytize antigens and display antigenic fragments on their surface are called ______-presenting cells.

antigen

Examples of pathogens are ______.

bacteria fungi viruses

Lymphatic vessels are absent from ______.

cartilage and bone

The process called ______ selection results in the formation of a clone of identical T cells programmed against the same epitope.

clonal

______ T cells attack foreign cells.

cytotoxic

Lymphatic vessels that carry lymph away from a lymph node are called _____ lymphatic vessels.

efferent

Skin belongs to the body's ______ line of defense.

first

B cells are the primary cell of ______ immunity and T cells are the primary cell of ______ immunity.

humoral, cell-mediated

The ______, part of the brain, regulates and maintains body temperature. Its set point is elevated during a fever.

hypothalamus

refers to the inability to produce a normal immune response, resulting from a lack of immune cells or other immune mediators such as complement.

immunodeficiency

The fluid contained in lymphatic vessels, which originates as tissue fluid, is called .

lymph

Lymph leaving the lymph nodes contains a large number of ______.

lymphocytes

Organisms that cause disease, such as bacteria or fungi, are considered .

pathogens

A cytolytic protein secreted by NK cells is ______

perforin

The T cell ______ response allows memory cells to mount a faster response upon exposure to the same pathogen later

recall

Hemopoiesis occurs in the ______ bone marrow.

red

The spleen and lymph nodes are classified as ______ lymphatic organs.

secondary

The characteristic of immunity describing how it is directed against a particular pathogen is ______.

specificity

The organ where T-cells mature is the ______.

thymus

______ lymphocytes originate in the red bone marrow, then finish maturation in the thymus.

thymus

The overlapping edges of the endothelial cells of a lymphatic capillary act as ______.

valves