Chapter 22: The Lymphatic System and Immunity

The primary response will peak how many days after an exposure?

10-17

What types of cells are APCs, and where in the body are they found?

APCs include macrophages in tissues throughout the body, B cells in blood and lymphatic tissue, and dendritic cells in mucous membranes and the skin.

Natural exposure to an infectious agent leads to:

Active Immunity

Antigens that induce an allergic reaction are called

Allergen

An acute allergic response can lead to:

Anaphylactic Shock

In clonal selection of B cells, which substance is responsible for determining which cells will eventually become cloned?

Antigen

What induces the production of a specific antibody?

Antigen

Which class of cells includes macrophages, B cells and dendritic cells?

Antigen Presenting Cells

What makes up the second line of defense?

Antimicrobial substances, natural killer cells and phagocytes, inflammation, and fever.

Which type of adaptive immunity will result from intravenous injection of immunoglobulins?

Artificially acquired passive immunity

How much more IgG is circulating in the blood in the secondary response than in the primary response?

At peak secretion, approximately 1000 times more IgG is produced in the secondary response than in the primary response.

Lymph capillaries are absent in which tissues?

Avascular tissues (cartilage, epidermis, cornea of the eye), the central nervous system, portions of the spleen, and red bone marrow.

What is the correct sequence of events in phagocytosis?

Chemotaxis, adherence, ingestion, digestion, killing

The thymus is most active during ________.

Childhood

Which anti-microbial substances promote cytolysis, phagocytosis and inflammation?

Complement Proteins

What is a small hormone that can stimulate or inhibit many normal cell functions?

Cytokine

In addition to cells infected by microbes, what other types of target cells are attacked by cytotoxic T cells?

Cytotoxic T cells attack some tumor cells and transplanted tissue cells, as well as cells infected by microbes.

The antibody molecule is held together by ________ bonds.

Disulfide

What are the functions of the lymphatic and immune system?

Drain excess interstitial fluid, transport dietary lipids, and carry out immune responses.

What are some examples of endogenous antigens?

Endogenous antigens include viral proteins, toxins from intracellular bacteria, and abnormal proteins synthesized by a cancerous cell.

What are the physical factors in the first line of defense?

Epidermis of skin, mucous membranes, mucus, hairs, cilia, lacrimal apparatus, saliva, urine, defecation, and vomiting.

What is the difference between an epitope and a hapten?

Epitopes are small immunogenic parts of a larger antigen; haptens are small molecules that become immunogenic only when they attach to a body protein.

True or False: Antigens only come from microbes.

False

True or False: NK cells are a type of neutrophil.

False

True or False: The adaptive immune system is specific for a given organ.

False

True or False: The cisterna chyli collects lymph from the lumbar trunks draining the upper limbs and from the intestinal trunk draining the digestive organs.

False

True or False: Type II Diabetes is an autoimmune disease.

False

What intensifies the effect of interferons and promotes the rate of repair?

Fever

What happens to foreign substances in lymph that enter a lymph node?

Foreign substances in lymph that enter a lymph node may be phagocytized by macrophages or attacked by lymphocytes that mount immune responses.

What do helper T cells do?

Function in the adaptive immune system activation

Which cells of the immune system are attacked by HIV?

HIV attacks helper T cells.

What stimulates an immune response ONLY when it is attached to a large carrier molecule?

Hapten

What causes heat during inflammation?

Heat results from increased blood flow and heat released by locally increased metabolic reactions.

What are the signs of inflammation?

Heat, redness, swelling, and pain.

Which cells display CD4 proteins and interact with MHC Class II antigens?

Helper T Cells

Which type of T cell participates in both cell-mediated and antibody mediated immune responses?

Helper T cells participate in both cell-mediated and antibody-mediated immune responses.

What induces vasodilation and permeability (increased fluid flow) to an infection site?

Histamine, kinins, prostaglandins, leukotrienes, and complement.

Which class of antibodies is mainly found in sweat, tears, breast milk and GI secretions?

IgA

Which immunoglobulin is a pentamer?

IgM

What is the function of the spleen?

Immune functions, destruction of blood-borne pathogens, removal of ruptured, worn out, or defective blood cells and platelets, storage of platelets, and production of blood cells during fetal life.

When B and T cells are fully developed and mature, they are described as being

Immunocompetent

The inability of the immune system to protect the body from a pathogen causes

Immunodeficiency Diseases

How does deletion differ from anergy?

In deletion, self-reactive T cells or B cells die; in anergy, T cells or B cells are alive but are unresponsive to antigenic stimulation.

Does inhalation promote or hinder the flow of lymph?

Inhalation promotes the movement of lymph from abdominal lymphatic vessels toward the thoracic region because the pressure in the vessels of the thoracic region is lower than the pressure in the abdominal region when a person inhales.

Which portion of the lymph node does not contain any lymphatic nodules.

Inner Cortex

What do interferons do?

Interfere with viral replication within cells

Which anti-microbial substances reduce viral replication (in uninfected cells)?

Interferons

What causes lymph from the small intestines to appear white?

Lipids

What is the major difference between lymph and interstitial fluid?

Location

Small organs associated with lymphatic vessels are termed ________.

Lymph Nodes

Is lymph more similar to blood plasma or interstitial fluid? Why?

Lymph is more similar to interstitial fluid than to blood plasma because the protein content of lymph is low.

When do lymphatic tissues begin to develop?

Lymphatic tissues begin to develop by the end of the fifth week of gestation.

The skeletal muscle and respiratory pumps are used in

Lymphatic, immune, and cardiovascular systems

Which cells become immunocompetent due to thymic hormones?

Lymphocytes

What chemicals are responsible for killing ingested microbes?

Lysozyme, digestive enzymes, and oxidants can kill microbes ingested during phagocytosis.

Which cells increase the permeability of blood vessels by releasing histamine?

Mast Cells

Which cell kills infected body cells and tumor cells?

Natural Killer Cells

Which type of adaptive immunity will result from mother-to-baby IgA transfer via breast feeding?

Naturally acquired passive immunity

Large clusters of lymph nodes occur in which regions?

Near the mammary glands and in the axillae and groin.

Which type of immunity defends against any type of invader?

Nonspecific

Which action makes microbes more susceptible to phagocytosis?

Opsonization

What causes pain during inflammation?

Pain results from injury of nerve fibers, irritation by microbial toxins, kinins, and prostaglandins, and pressure due to edema.

What are the digestive-tract associated lymphatic tissues?

Peyer's patches, appendix, and tonsils.

Innate immune system defenses include ________.

Physical factors, chemical factors, antimicrobial substances, natural killer cells, phagocytes, inflammation, and fever.

Antibodies that act against a particular foreign substance are released by ________.

Plasma Cells

The ability of an antigen to react specifically with the antibodies or cells it has provoked is called

Reactivity

What tissue contains stem cells that develop into lymphocytes?

Red bone marrow contains stem cells that develop into lymphocytes.

What causes redness during inflammation?

Redness results from increased blood flow due to vasodilation.

Which lymphatic structure drains lymph from the right upper limb and the right side of the head and thorax?

Right Lymphatic Duct

What are the chemical factors in the first line of defense?

Sebum, lysozyme, gastric juice, and vaginal secretions.

How many different kinds of antibodies will be secreted by the plasma cells in one clone?

Since all of the plasma cells are part of the same clone, they secrete just one kind of antibody.

Both lymph and venous blood flow are heavily dependent on ________.

Skeletal muscle contractions and differences in thoracic pressures due to respiratory movement

What negatively affects the immune system?

Smoking, lack of sleep, sedentary lifestyle, and stress.

Lack of resistance is also known as:

Susceptibility

What causes swelling during inflammation?

Swelling results from leakage of fluid from capillaries due to increased permeability.

To become activated, what requires being bound to a foreign antigen AND simultaneous costimulation?

T Cell

Which cell is considered to be the most important cell in the immune system?

T Helper Cells

Which type of lymphocytes mature in the thymus?

T cells mature in the thymus.

What is the function of the CD8 protein of a cytotoxic T cell?

The CD8 protein of a cytotoxic T cell binds to the MHC-I-molecule of an infected body cell to help anchor the T cell receptor (TCR)-antigen interaction so that antigen recognition can occur.

Which pathway for activation of complement involves antibodies? Explain why.

The classical pathway for the activation of complement is linked to antibody-mediated immunity because Ag-Ab complexes activate C1.

A sentinel node is ________.

The first node to receive lymph from an area suspected to be cancerous

What are the first and second signals in activation of a T cell?

The first signal in T cell activation is antigen binding to a TCR; the second signal is a costimulator, such as a cytokine or another pair of plasma membrane molecules.

Which lymphatic vessels empty into the cisterna chyli, and which duct receives lymph from the cisterna chyli?

The left and right lumbar trunks and the intestinal trunk empty into the cisterna chyli, which then drains into the thoracic duct.

What effect does age have on the size of the thymus?

The thymus initially increases in size and then decreases in size from adolescence through old age.

What is the function of the variable regions in an antibody molecule?

The variable regions recognize and bind to a specific antigen.

The thymus develops from the

Third Pharyngeal Pouch

The left subclavian vein receives lymph from

Thoracic Duct

The lymph from the right foot empties into the

Thoracic Duct

Which organ produces a hormone that promotes maturation of T cells?

Thymus

What are the organs of the immune system?

Thymus, lymph nodes, spleen, and lymphatic nodules.

True or False: Digested fats are absorbed from the intestine by the lymph capillaries.

True

True or False: Isografts are between identical twins.

True

True or False: Lymphatic capillaries are permeable to proteins.

True

True or False: Lymphatic vessels drain excess interstitial fluid from connective tissues.

True

True or False: The causative agent in acquired immune deficiency syndrome (AIDS) is a virus that recognizes CD4 proteins.

True

True or False: The lymphatic capillaries function to absorb the excess protein-containing interstitial fluid and return it to the bloodstream.

True

True or False: Tolerance is developed during fetal life.

True

True or False: When tissues are inflamed, lymphatic capillaries develop openings that permit uptake of large particles such as cell debris, pathogens, and cancer cells.

True

The primary immune response has a large lag due to what?

While B cells proliferate and differentiate into plasma cells.

After birth, what are the main functions of the spleen?

White pulp of the spleen functions in immunity; red pulp of the speen performs functions related to blood cells.