Which statement is true about innate immunity?
Innate immunity is the first, and most general, mechanism of protection against pathogens.
A strain of fruit fly lacks the ability to produce Dicer-2 protein will most likely be susceptible to which of the following types of infections?
viral
Vertebrate immune cells, which are phagocytic, include which of the following?
neutrophils, macrophages, and dendritic cells
Which of the following cells and signaling molecules are involved in the initial stages of the inflammatory response?
mast cells and histamines
Which of the following are typical features of an inflammatory response?
increased activity of phagocytes in an inflamed area
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
Which of the following can trigger septic shock?
certain bacterial infections
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
Acidity in human sweat is part of which type of immune system?
innate immunity
Which of the following protects both the eyes and the respiratory tract against infections?
the secretion of lysozyme onto their surfaces
Which statement correctly describes the complement system?
a group of proteins that act together in a cascade fashion
Which response is triggered when bacteria enter the body through a small cut in the skin?
activation of a group of proteins called complement
Mucus occurs in both the respiratory and digestive tracts. Which answer best describes the main immunological function of mucus?
to physically trap pathogens
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
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
7) 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
Within a differentiated B cell, the activity of which molecule results in the rearrangement of DNA sequences between variable regions and joining regions?
recombinase
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
An organism that lacks their thymus would __
be unable to differentiate and mature T cells
Which statement best describes the concept of clonal selection?
an antigen can provoke production of high amounts of specific antibodies
) Which of the following components make up a light chain of an immunoglobulin (Ig) molecule, of any class, with regions symbolized as C or V, H or L?
one C region and one V region
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
Use the following information to answer the following question.
An otherwise healthy student in your class was infected with Epstein Barr virus (EBV) (the virus that causes infectious mononucleosis) when she was a child, at which time she had merely experienced a mild sore throat and swollen lymph nodes in her neck. When she is exposed to EBV again later in life, she does not get sick or develop any symptoms of mononucleosis.
Which of the following statements explains why your classmate does not exhibit symptoms of EBV infection?
Memory T cells recognized the virus upon the second exposure and activated cells that destroyed the virally infected cells.
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 the T cell receptor
Vaccination offers protection against future exposure to pathogens because it ________
triggers clonal expansion of lymphocytes
Which of these is a characteristic of adaptive immunity but not innate immunity?
memory
Lymphocytes mature in the ____
thymus and bone marrow
Which of the following statements describe a component of the clonal selection theory of how the adaptive immune system functions?
Each lymphocyte has a unique membrane receptor that recognizes one
antigen.
When the lymphocyte binds an antigen, it is activated
and begins dividing to form many btestbanks.com identical copies of itself.
Cloned cells descend from an activated lymphocyte and persist even after the pathogen is eliminated
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 of the following are similarities between B cells and T cells
Both undergo clonal selection after encountering an
antigen.
Both maintain an immunological memory of previously
encountered antigens
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 btestbanks.com accurately describes this cell
memory cell
Which of the following statements about epitopes is incorrect?
There is a one-to-one correspondence between antigen and epitope.
If a T cell antigen receptor was composed of only a single alpha chain, the receptor would ________.
not be able to bind to antigens effectively
Breast feeding confers which type of immunity to an infant?
passive immunity
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 statement correctly describes both CD4 and CD8 proteins?
molecules present on the surface of T cells that interact with major histocompatibility (MHC) molecules
T cells of the immune system include ______
cytotoxic and helper cells
B cells are stimulated to differentiate under which of the following conditions?
helper T cells release cytokines
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 enhances phagocytosis of microbes by macrophages?
the binding of antibodies to the surface of microbes
antibody-mediated opsonization of microbes
Which of the following can result in naturally acquired passive immunity?
placental transfer of antibodies
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 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
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 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 of the following components of the immune system destroys cancer cells by forming holes in plasma membranes and triggering apoptosis?
cytotoxic t cells
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
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 mutation in flu viruses alters the surface proteins in infected host cells
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 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 (oral or genital) whose reproduction is triggered by physiological or emotional stress in the host
Which treatment is most appropriate for an individual complaining of watery, itchy eyes and sneezing after being given a flower bouquet?
antihistamines
Which of the following would help a virus avoid triggering an effective adaptive immune response?
having frequent mutations in genes for surface proteins
building the viral shell from host proteins
infecting and killing helper T cells
Which of the following is the best definition of autoimmune disease
a condition in which self molecules are treated as nonself (loss of self-tolerance)
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
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 these is not part of insect immunity?
activation of natural killer cells
An epitope associates with which part of an antigen receptor or antibody?
variable regions of a heavy chain and light chain combined
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 a pathogen; cytotoxic T cells kill pathogen-infected host cells
Which of the following statements is not true? 43.2
A lymphocyte has receptors for multiple different antigens.
Which of the following should be the same in identical twins?
the set of MHC molecules produced
Vaccination increases the number of ____
lymphocytes with receptors that can bind to the pathogen
Which of the following would not help a virus avoid triggering an adaptive immune response?
producing proteins very similar to those of other viruses