immune system

Which of the following is the best definition of autoimmune disease?

A condition in which self molecules are treated as non-self (loss of self tolerance)

Which statement correctly describes the complement system?

A group of proteins that act together in a cascade fashion

Which of the following statements is not true?

A lymphocyte has receptors for multiple different antigens

Which response is triggered when bacteria enter the body through a small cut in the skin?

Activation of a group of proteins called complement

Which statement best describes the concept of clonal selection?

An antigen can provoke production of high amounts of specific antibodies

Which option best describes how a viral antigen, like EBV, is recognized by T cells?

An antigen fragment is presented within class I MHC to tell T cell receptor

A patient has a high level of mast cell activity, dilation of blood vessels, and acute drop in blood pressure. Which condition is most consistent with these symptoms?

Anaphylactic shock immediately following exposure to an allergen

Which treatment is most appropriate for an individual complaining of watery, itchy eyes and sneezing after being given a flower bouquet?

Antihistamines

Which statement best describes the difference between responses of effector B cells (plasma cells) and those of cytotoxic T cells?

B cells secrete antibodies against pathogen; cytotoxic T cells kill pathogen-infected host cells

The structure of an antibody is similar to the extracellular component of which receptor?

BCR

An organism that lacks their thymus would ________.

Be unable to differentiate and mature T cells

Which immune cells bind MHC molecules on APCs via CD8 coreceptors on their cell surfaces?

CTLs

Which of the following components of the immune system destroys cancer cells by forming holes in plasma membranes and triggering apoptosis?

Cytotoxic T cells

The number of major histocompatibility (MHC) protein combinations possible in a given population is enormous. However, an individual in the population has a far more limited array of MHC molecules because

Each of the MHC genes has a large number of alleles but each individual only inherits two for each gene

Which of the following diseases is not due to autoimmunity?

HIV/AIDS

B cells are stimulated to differentiate under which of the following conditions?

Helper T cells release cytokines

Which of the following gives the best example for the ability of some viruses to remain inactive (latent) for a period of time?

Herpes simplex viruses whose reproduction is triggered by physiological or emotional stress in the host

Which of the following statements describe a component of the clonal selection theory of how the adaptive immune system functions? I-Each lymphocyte has a unique membrane receptor that recognizes one antigen. II-When the lymphocyte binds an antigen, it is activated and begins dividing to form many identical copies of itself. III-Cloned lymphocytes have slight differences and are selected by the spleen for removal if they do not bind an antigen. IV-Cloned cells descend from an activated lymphocyte and persist even after the pathogen is eliminated.

I, II and IV

Which of the following would help a virus avoid triggering an effective adaptive immune response? I-having frequent mutations in genes for surface proteins II-building the viral shell from host proteins III-producing proteins very similar to those of other viruses IV-infecting and killing helper T cells

I, II and IV

Which of the following are similarities between B cells and T cells? I-Both recognize antigens using immunoglobulin receptors. II-Both undergo clonal selection after encountering an antigen. III-Both maintain an immunological memory of previously encountered antigens.

II and III

Some people are allergic to dust mites, which are tiny insects that commonly live in house dust. Which of the following is the most immediate outcome if someone who is allergic to dust mites inhales dust years after they are first exposed to dust mites?

IgE antibodies bound to mast cells bind the dust mite allergen

What is the most abundant antibody class detected in the serum upon reexposure to a pathogen or in reaction to a vaccine?

IgG

The first antibody class to appear in the serum in response to a newly encountered pathogen is ________.

IgM

The acquired ability to prevent an unnecessary or destructive immune reaction to a harmless foreign particle, such as a food protein, is called ________.

Immune tolerance

Wiskott-Aldrich syndrome is an inherited X-linked recessive disorder characterized by low platelet count and a compromised immune system among other symptoms. Which answer best describes Wiskott-Aldrich syndrome?

Inborn immunodeficiency disease

Which of the following are typical features of an inflammatory response?

Increased activity of phagocytes in an inflamed area

A boy falls while riding his bike. A scrape on his hand almost immediately begins to bleed and becomes red, warm, and swollen. Which type of response is most consistent with these symptoms?

Inflammatory response

Which treatment could relieve the symptoms of an individual who has been bitten by a poisonous snake that has a fast-acting toxin?

Injection of antibodies to the toxin

Acidity in human sweat is part of which type of immune system?

Innate immunity

Which statement is true about innate immunity?

Innate immunity is the first, and most general, mechanism of protection against pathogens.

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

Which answer describes an advantage of having a system of adaptive immunity?

It enables a rapid defense against an antigen that has been previously encountered

Which organelle do phagocytes use to digest engulfed particles?

Lysosome

Which of the following is both a phagocyte and an antigen-presenting cell?

Macrophage

Which of the following cells and signaling molecules are involved in the initial stages of the inflammatory response?

Mast cells and histamines

Which of these is a characteristic of adaptive immunity but not innate immunity?

Memory

A certain cell type has existed in the blood and tissue of its vertebrate host's immune system for over 20 years. One day, it recognizes a newly arrived antigen and binds to it, subsequently initiating a secondary immune response in the body. Which of the following cell types most accurately describes this cell?

Memory cell

What "self" pattern is identified by NK cells?

Missing self

Which statement correctly describes both CD4 and CD8 proteins?

Molecules present on the surface of T cells that interact with major histocompatibility (MHC) molecules

Which innate immune system component uses MHC I molecules directly in its defense strategy?

NK cells

Vertebrate immune cells, which are phagocytic, include which of the following?

Neutrophils, macrophages and dendritic cells

Breastfed infants typically are resistant to disease because of

Passive immunity

Breastfeeding confers which type of immunity to an infant?

Passive immunity

Which of the following can result in naturally acquired passive immunity?

Placental transfer of antibodies

Which of the following is crucial to activation of the adaptive immune response?

Presentation of MHC (major histocompatibility complex) antigen complex on a cell surface

Yearly vaccinations for influenza viruses are necessary for humans because

Rapid mutilation in flu viruses alters the surface proteins in infected host cells

Clonal selection and differentiation of B cells activated by antigen exposure leads to the production of ________.

Short lived plasma cells that secrete antibodies for the antigen

Foreign particles circulating in the blood are filtered by the

Spleen

Which statement best describes what causes the clumping of antigens when antibodies bind antigens?

The antibody has two identical binding sites

Which of the following components of the immune system is most likely to be the same in identical twins?

The kinds of major histocompatibility (MHC) molecules produced

A phagocytic cell has a mutation in a gene for a hydrolytic enzyme that renders the enzyme nonfunctional. What is the most likely effect of the mutation when this phagocytic cell ingests a pathogen?

The lysosome will not degrade the pathogen effectively

Which statement best describes an account of immunological memory?

The observation that someone who had recovered from the plague could safely care for those newly diseased

Which of the following protects both the eyes and the respiratory tract against infections?

The secretion of lysozyme onto their surfaces

Benadryl is an antihistamine. Which of the following is most likely to occur if a person that was stung by a bee takes Benadryl?

The site of injury will become less red and swollen

Which of the following best explains why a bone marrow transplant may not be appropriate from a given donor to a given recipient even though they are compatible for blood transfusions?

Their blood types may match but major histocompatibility (MHC) proteins may not be a match

Which option best describes why Jenner's use of cowpox virus as a vaccine against the smallpox virus was successful?

There are some epitopes (antigenic determinants) common to both pox viruses

Which of the following statements about epitopes is incorrect?

There is a one to one correspondence between antigen and epitope

Mucus occurs in both the respiratory and digestive tracts. Which answer best describes the main immunological function of mucus?

To physically trap pathogens

Which of the following are molecules on mammalian cells that recognize macromolecules that are present in or on certain groups of pathogens?

Toll - like receptors

Vaccination offers protection against future exposure to pathogens because it ________.

Triggers clonal expansion of lymphocytes

You and your friend were equally exposed to a virus, but over the next few days, only your friend acquired flu-like symptoms and was ill for almost a week before recovering. Which one of the following is a logical explanation for this?

You had an immunological memory of that virus

T cells of the immune system include

cytotoxic and helper cells

Allergy to pollen is classified as:

immediate hypersensitivity

Vaccination increases the number of

lymphocytes with receptors that can bind to the pathogen

A potential cause of acquired autoimmunity is

molecular mimicry

Which of the following would not help a virus avoid triggering an adaptive immune response?

producing proteins very similar to those of other viruses

Autoantibodies are probably involved in:

systemic lupus erythematosus

Which of the following should be the same in identical twins?

the set of MHC molecules produced

An epitope associated with which part of an antigen receptor or antibody?

variable regions of a heavy chain and light chain combined

Although interferons have several effects, they are particularly useful against infections with which type of pathogen?

viruses