Ch. 43 Immune System

If a person's bone marrow were destroyed by radiation, which of the following cells could not be produced?

A) B cells B) T cells C) erythrocytes D) neutrophils

Which of the following is true of both T cells and B cells?

A) They produce effector cells against specific pathogens. B) They are produced from stem cells of the bone marrow.

The MHC is important in

A) distinguishing self from nonself D) identifying cancer cells.

Physical barriers to invasion by other organisms

A) include the skin and the mucous membranes. B) are difficult for bacteria and viruses to penetrate. C) may work in conjunction with secretions like tears, perspiration, and mucus

Which cells will respond whether you have a viral infection or a bacterial infection?

A) plasma cells B) helper T cells

The lymphatic system involves which of the following organs?

A) spleen and lymph nodes B) adenoids and tonsils C) appendix and special portions of the small intestine

Phagocytosis of microbes by macrophages is enhanced by

A) the binding of antibodies to the surface of microbes. B) antibody-mediated agglutination of microbes.

Which statement about antibodies is false?

Antibodies bind with foreign cells and lyse them.

Which of the following best describes the difference in the way B cells and cytotoxic T cells respond to invaders?

B cells secrete antibodies against a virus; cytotoxic T cells kill virus-infected cells.

Clonal selection is the division of ________ that have been stimulated by binding to an antigen, which results in the production of cloned ________.

B cells; plasma cells and memory cells

After an Rh-positive baby is born to an Rh-negative mother, the mother is treated with antibodies specific for the Rh factor. The purpose of this treatment is to

B) prevent her from generating memory B cells specific for the Rh factor C) protect her future Rh-positive babies.

What aspect of the immune response would a patient who has a parasitic worm infection and another patient responding to an allergen such as ragweed pollen have in common?

Both patients would have increased levels of IgE.

Why can normal immune responses be described as polyclonal?

Diverse antibodies are produced for different epitopes of a specific antigen.

If a newborn were accidentally given a drug that destroyed the thymus, what would most likely happen?

His T cells would not undergo the test of self-tolerance

The following events occur when a mammalian immune system first encounters a pathogen. Place them in correct sequence and then choose the answer that indicates that sequence. I. Pathogen is destroyed. II. Lymphocytes secrete antibodies. III. Antigenic determinants from pathogen bind to antigen receptors on lymphocytes. IV. Lymphocytes specific to antigenic determinants from pathogen become numerous. V. Only memory cells remain.

III, IV, II, I, V

Which of the following statements about humoral immunity is correct?

It is mounted by lymphocytes that have matured in the bone marrow.

An immune response to a tissue graft will differ from an immune response to a bacterium because

MHC molecules of the host may stimulate rejection of the graft tissue.

All of the following are usually considered disorders of the immune system except

MHC-induced transplant rejection

A patient can produce antibodies against some bacterial pathogens, but he does not produce antibodies against viral infections. This is probably due to a disorder in which cells of the immune system?

T cells

In order to investigate the immune system of an invertebrate animal, a scientist grafts a section of epidermis from one earthworm to another. What might be the result of such an experiment?

The graft will be recognized as nonself and rejected.

How do people contract salmonella poisoning?

The microbe can survive the acidic environment of the stomach and resist lysosomal degradation in macrophages

Jenner successfully used cowpox virus as a vaccine against the virus that causes smallpox. Why was he successful even though he used viruses of different kinds?

There are some antigenic determinants common to both pox viruses.

Which statement about the complement system is true?

These proteins are one group of antimicrobial proteins

What happens to people who receive flu vaccinations?

They develop passive immunity to the flu.

Which of the following is a false statement about innate immunity?

They must be primed by the presence of antigen

Which of the following is not true about helper T cells?

They recognize polysaccharide fragments presented by class II MHC molecules.

A bacterium entering the body through a small cut in the skin will do which of the following?

activate a group of proteins called complement

Which of the following is not a component of an insect's defense against infection?

activation of natural killer cells

The clonal selection theory is an explanation for how

an antigen can provoke development of very few cells to result in production of high levels of specific antibodies.

Which of the following is not part of the body's innate, nonspecific defense system?

antibodies

Which of the following is the last line of defense against an extracellular pathogen?

antibody production by plasma cells

Which of the following is (are) not involved in the activation and functioning of cytotoxic T cells?

antigen-presenting cells

The clonal selection theory implies that

antigens activate specific lymphocytes

A patient reports severe symptoms of watery, itchy eyes and sneezing after being given a flower bouquet as a birthday gift. A reasonable initial treatment would involve the use of

antihistamines

Which of the following could prevent the appearance of the symptoms of an allergy attack?

blocking the attachment of the IgE antibodies to the mast cells

Which action below is affected by an antihistamine?

blood vessel dilation

Which of the following is a pathway that would lead to the activation of cytotoxic T cells?

body cell becomes infected with a virus → synthesis of new viral proteins → class I MHC molecule-antigen complex displayed on cell surface

Which of the following molecules is incorrectly paired with a source?

chemokines—cytotoxic T cells

These cells are involved in cell-mediated immunity and destroy virally infected cells.

cytotoxic T cells

These cells are involved in cell-mediated immunity, and they respond to class I MHC molecule-antigen complexes

cytotoxic T cells

HIV targets include all of the following except

cytotoxic T cells.

Which of the following are all types of T cells that participate in the immune response system?

cytotoxic and helper cells

Each indication below is a clinical characteristic of inflammation except

decreased temperature

A major difference between active and passive immunity is that active immunity requires

direct exposure to a living or simulated pathogen.

What are antigens?

foreign molecules that trigger the generation of antibodies

Which cell type interacts with both the humoral and cell-mediated immune pathways?

helper T cells

B cells interacting with helper T cells are stimulated to differentiate when

helper T cells release cytokines

Which of the following would be most beneficial in treating an individual who has been bitten by a poisonous snake that has a fast-acting toxin?

injection of antibodies to the toxin

A nonfunctional CD4 protein on a helper T cell would result in the helper T cell being unable to

interact with a class II MHC-antigen complex.

The successful development of a vaccine to be used against a pathogen

is dependent on the surface antigens of the pathogen not changing

Both lysozyme and cytotoxic T cells

kill cells through chemical interactions.

The innate immunity that protects a person digging in the garden from developing a microbial infection includes all of the following except

lymphocytes.

These cells have a function that is similar to the function of dendritic cells

macrophages

Which cell and signaling molecule are responsible for initiating an immune response?

mast cells: histamine

There is usually no concern if the mother's blood type is different from that of the developing fetus unless the Rh factor is involved. This is because

maternal Rh antibodies can cross the placenta, whereas those against the ABO blood groups cannot.

Which of the following cell types are responsible for initiating a secondary immune response?

memory cells

These cells are involved in innate immunity, and a person lacking these cells may have a higher than normal chance of developing malignant tumors.

natural killer cells

A person exposed to a new cold virus would not feel better for one to two weeks because

phagocytic cells must first be activated by the complement system.

Naturally acquired passive immunity would involve the

placental transfer of antibodies

Which of the following types of cells is not involved in both antibody-mediated immunity and cell-mediated immunity?

plasma cells

Which of these cells secretes antibodies?

plasma cells

B cells that have been stimulated by interleukin-2 develop into

plasma cells.

Double-stranded viral DNA is incorporated into a host cell as a

provirus

Inflammatory responses may include all of the following except

reduced permeability of blood vessels to conserve plasma.

In the inflammatory response, the absence of which of the following would prevent all the others from happening?

release of histamine

Which of the following is a characteristic of the early stages of local inflammation?

release of histamine

A person with AIDS would be unlikely to suffer from which of the following diseases?

rheumatoid arthritis

The genetic material of HIV consists of

single-stranded RNA

Which choice could be used as an analogy to describe how HIV affects the body?

snipping the wires coming from a car battery so that no electricity flows to the car components

CD4 and CD8 are proteins

that are present on the surface of T cells where they enhance cellular interaction.

Which of the following results in long-term immunity?

the administration of the chicken pox vaccine

What would be the major concern for an individual with type A blood who receives a transfusion of type B blood?

the antibodies in the serum of the recipient

Which of the following is not a part of an antibody molecule?

the epitope

A transfusion of type A blood given to a person who has type O blood would result in which of the following?

the recipient's anti-A antibodies clumping the donated red blood cells

What is the single most important event establishing a primary immune response?

the recognition of self versus foreign

Both the eye and the respiratory tract are protected against infections by which of the following?

the secretion of lysozyme onto their surface

When antibodies attack antigens, clumping of the affected cells generally occurs. This is best explained by

the shape of the antibody with at least two binding regions

An epitope associates with which part of an antibody?

the variable regions of a heavy chain and light chain combined

Antibodies of the different classes IgM, IgG, IgA, IgD, and IgE differ from each other in the

way they interact with the antigen

In which of the following situations will helper T cells be activated?

when an antigen is displayed by a dendritic cell