BIOL 2321 Exam 4 Practice Test Questions

BONUS Which of the following bacteria would you expect to cause the most severe blood disease in a susceptible host? A) a rapidly growing encapsulated bacteria B) a flagellated acidophile C) a biofilm-producing strain D) a piliated slow -growing Gram negative E) a halophilic psychrophile

?

Which of the following organisms can cause gastrointestinal symptoms without infecting the affected individual? A) Salmonella enterica B) Staphylococcus aureus C) Giardia lamblia D) Shigella

?

Which represents acquisition of antibodies by a baby? A) Adaptive immunity that is naturally acquired and is active B) Adaptive immunity that is naturally acquired and is passive C) Adaptive immunity that is artificially acquired and is active D) Adaptive immunity that is artificially acquired and is passive E) None of the above

A) Adaptive immunity that is naturally acquired and is active

Endotoxins are A) Associated with lipid A of the LPS layer. B) Secreted from the cell. C) Associated with gram-positive bacteria. D) Capsules. E) None of the above.

A) Associated with lipid A of the LPS layer.

Which pair is correctly matched? A) Epitope: the part of the antigen that an antibody binds to B) Immunogenic strength: lipids> carbohydrate > protein C) Antigen-presenting cells: typically the way in which B cells see antigen D) Person with type B blood: have anti-B antibodies in serum E) None of the above are correctly matched

A) Epitope: the part of the antigen that an antibody binds to

The most abundant class of antibodies in blood serum and a type that can act as an opsonin, activate complement, and neutralize pathogens is: A) IgG B) IgM C) IgA D) IgD E) IgE

A) IgG

Which of the following among A-D is not a characteristic of T cells? A) Like macrophages, cytotoxic T cells can also phagocytize cells B) Cytotoxic T cells respond to antigen bound to MHC class I molecules C) Certain T helper cells bind to and activate macrophages and dendritic cells D) Certain T helper cells activate B cells for antibody production E) All of the above are characteristics of T cells

A) Like macrophages, cytotoxic T cells can also phagocytize cells

Herd immunity will not protect un-immunized individuals from diseases such as botulism or tetanus. A) True B) False

A) True

Chlamydia trachomatis is a bacterial STD that lives intracellularly within human host cells; what adaptive immune response would most likely prevail in this infection? A) cytotoxic T cells B) macrophages C) memory B cells D) plasma B cells E) defensins

A) cytotoxic T cells

Which of the following is a mostly non-proteinaceous, yet toxic, compound found in all gram-negative bacteria? A) endotxin B) exotoxin C) capsule D) type III secretion system E) two of the above are correct

A) endotoxin

Natural killer cells target: A) infected cells that have lost MHC surface proteins B) bacterial cells that are coated with complement C) infected cells bound with antibody D) extracellular viruses E) All the above

A) infected cells that have lost MHC surface proteins

Staphylococcus aureus is a normal skin inhabitant that is harmless unless a break in the skin occurs; under these conditions, this bacterium can cause an infection. For this reason, S. aureus is referred to as a/an: A) opportunistic pathogen B) commensal C) parasite D) primary pathogen E) mutualist

A) opportunistic pathogen

Opsonization is a process whereby the innate and adaptive immune mechanisms work together: A) to phagocytize an invader B) to activate complement proteins C) for antibody secretion D) to destroy cancer cells E) during apoptosis

A) to phagocytize an invader

Most diarrheal diseases are of what origin? A) viral B) bacterial C) fungal D) archaeal E) any of the above

A) viral

All of the following occur during inflammation. Of these choices, which would occur first? A) Neutrophil exit from blood vessel B) Cytokine release C) Neutrophils "stick" to blood vessel wall D) Repair E) Vasodilation D) Swelling

B) Cytokine release

These antibodies can form a pentamer comprised of 5 monomers; this antibody type is: A) IgG B) IgM C) IgA D) IgD D) IgE

B) IgM

Which statement is false concerning the plague? A) Yersinia pestis is the bacterium responsible for this disease. B) Plague epidemics occur when infected mosquitos transfer the disease from human to human. C) The septicemic form of the plague is not the most infectious form of the disease. D) Plague is an example of a systemic infection. E) Part of the disease process by the plague bacteria is the formation of buboes, due to the enlargement of lymph nodes

B) Plague epidemics occur when infected mosquitos transfer the disease from human to human.

Which of the following is not as sociated with innate immunity? A) Lysozyme in saliva B) Proliferation of plasma B cells C) Macrophage engulfment of bacteria D) Cilia in trachea E) Production of defensins

B) Proliferation of plasma B cells

Which of the following is not associated with innate immunity? A) Lysozyme in saliva B) Proliferation of plasma B cells C) Macrophage engulfment of bacteria D) Cilia in trachea E) Production of defensins

B) Proliferation of plasma B cells

Which of the following pairs is mismatched? A) Interferons: secreted by eukaryotic cells in response to intracellular infection, specifically viral infections. B) Toll-like receptors: they directly kill pathogens C) Defensins: form channels in bacterial cytoplasmic membranes, ultimately killing the cell D) Endogenous pyrogen: leads to an increase in the hypothalamic temperature set point E) PAMPS: bacterial cell wall, flagellum, pili, or the LPS of a Gram-negative bacterium are examples of this

B) Toll-like receptors: they directly kill pathogens

Which state is not accurate regarding bacterial exotoxins? A) Exotoxins are protein toxins made and secreted by both gram-positive and gram-negative bacteria B) Toxins with ADP ribosyltransferase activity all produce the same effect in affected individuals C) Cholera toxin results in the loss of tremendous amounts of water from an affected individual D) Exotoxins can cause disruption of cell membranes or inhibit eukaryotic ribosomes E) Structurally, AB exotoxins possess a binding subunit and a subunit possessing the toxin activity

B) Toxins with ADP ribosyltransferase activity all produce the same effect in affected individuals

All the following would be of benefit to extracellular pathogens, except A) the presence of a capsule B) ability to prevent the fusion of a phagosome and lysosome C) ability to prevent of opsonization D) ability to alter cell surface proteins via phase variation E) There are no exceptions; all are of benefit to extracellular

B) ability to prevent the fusion of a phagosome and lysosome

The ability to lyse a phagosome or to prevent the fusion of a phagosome and lysosome would be of particular benefit to A) any pathogen. B) an intracellular pathogen. C) a macrophage. D) an extracellular pathogen. E) none of the above

B) an intracellular pathogen.

Immunoprecipitation occurs when A) antigen is present in excess over antibody B) antigen and antibody ratios are approximately equal C) antibody is present in excess over antibody D) none of the above

B) antigen and antibody ratios are approximately equal

Which white blood cell type is not correctly matched with its proper function or feature? A) neutrophils: called polymorphonuclear leukocytes; can exit blood vessels and enter infected tissue B) basophils: primary phagocytic cell type that fights infection C) macrophages: important phagocytic cell type; can reside in certain tissues or wander around thebody D) dendritic cells: works with adaptive immune system as an antigen presenting cell E) monocyte: outside the blood, differentiate into macrophages and dendritic cell \s

B) basophils: primary phagocytic cell type that fights infection

An organism found on human skin that derives benefit from the host but does not harm it is described as a/an: A) parasite B) commensalistic organism C) opportunistic pathogen D) pathogen E) mutualist

B) commensalistic organism

Which of the following would be considered an aspect of the adaptive immune response? A) interferons B) lymphocytes C) defensins D) natural killer cells E) all of the above

B) lymphocytes

A certain pathogen is easily acquired by individuals, and has less than a 1% mortality rate among those unfortunate enough to acquire it. This pathogen is A) highly infectious and highly virulent. B) highly infectious and minimally virulent. C) minimally infectious and minimally virulent. D) minimally infectious and highly virulent. E) None of the above

B. highly infectious and minimally virulent.

The best definition of an antigen is A) A pathogen. B) A chemical that combines with antibodies. C) A chemical that elicits an antibody response and can combine with these antibodies. D) Something foreign in the body. E) A protein that combines with antibodies.

C) A chemical that elicits an antibody response and can combine with these antibodies.

Which represents vaccination A) Adaptive immunity that is naturally acquired and is active B) Adaptive immunity that is naturally acquired and is passive C) Adaptive immunity that is artificially acquired and is active D) Adaptive immunity that is artificially acquired and is passive E) None of the above

C) Adaptive immunity that is artificially acquired and is active

The antibodies found on mucosal surfaces and in mucosal secretions and functions to interfere with pathogen adherence is: A) IgG B) IgM C) IgA D) IgD E) IgE D) 2 are true

C) IgA

Which pair is not correctly matched? A) Hapten: not immunogenic by itself; requires a carrier protein B) Threshold dose: elicits a strong immune response C) Immunogenic strength: small protein > large protein D) Antigen-presenting cells: typically the way in which T cells see antigen E) Person with type B blood: has anti-A antibodies in serum

C) Immunogenic strength: small protein > large protein

The reservoir of infection: A) Is a toxic produced by the pathogen B) Is also known as fomite C) Is the source of the pathogen D) None of the above

C) Is the source of the pathogen

Which of the following is not correct about malaria? A) Plasmodium species are the causative agents of malaria; they are protozoans. B) Plasmodium parasites avoid the immune system by constantly changing cell surface proteins. C) Malaria is an infection of the gastrointestinal system. D) The Anopheles mosquito is the vector for transmission of malaria. E) Plasmodium differentiates into different forms during the infection.

C) Malaria is an infection of the gastrointestinal system.

BONUS Why is antibiotic treatment not typically prescribed for staphylococcal food poisoning? A) The bacterium is a multidrug-resistant pathogen. B) No antibiotic is useful because its a mixed infection. C) No cells infect the body to cause the disease symptoms. D) The causative agent is a MRSA. E) None of the above.

C) No cells infect the body to cause the disease symptoms.

Which is a non-communicable disease A) Influenza B) COVID-19 C) Tetanus D) Meningitis E) Plague F) all are communicable diseases

C) Tetanus

Which of the following is not a characteristic of T cells? A) They originate in bone marrow and mature in the thymus. B) Unlike B cells, certain T cells can directly kill infected host cells. C) When one is immunized with a vaccine, T cells are the primary responders in the body. D) They can secrete cytokines when activated. E) They recognize antigens associated with MHC proteins

C) When one is immunized with a vaccine, T cells are the primary responders in the body.

Extracellular pathogens can attempt to avoid immune detection by A) inhibiting phagosome-lysosome fusion. B) growing within a phagolysosome. C) altering their cell-surface proteins. D) all of the above E) none of the above

C) altering their cell-surface proteins.

Which of the following nonspecific defense mechanisms does not need to be synthesized, and is already present in blood and available to respond immediately to infection? A) interferon B) defensin C) complement D) lysozyme E) prostaglandins

C) complement

Antigens coated with antibody can lead to all of the follow except A) complement activation B) phagocytosis C) movement of neutrophils out of capillary blood vessels during inflammation D) agglutination E) neutralization of toxin or block adherence of bacteria to tissues

C) movement of neutrophils out of capillary blood vessels during inflammation

Antigens coated with antibody can lead to all the following, except A) complement activation B) phagocytosis C) movement of neutrophils out of capillary blood vessels during inflammation D) agglutination E) neutralization of toxin or block adherence of bacteria to tissues

C) movement of neutrophils out of capillary blood vessels during inflammation

In immunology, the term clonal selection best refers to: A) the multiple types of cells needed to generate an antigenic-specific response B) the ability of one B cell to produce antibodies to multiple antigens C) the ability of a specific B cell subset to proliferate upon exposure to a specific epitope D) the ability of memory B cells to induce a quick secondary antibody response E) the process of opsonizing antigen for rapid phagocytic degradation

C) the ability of a specific B cell subset to proliferate upon exposure to a specific epitope

Extravasation by neutrophils, vasodilation of local blood vessels, and phagocytosis are all a part of A) antibody formation B) activation of complement C) the inflammatory response D) opsonization E) septicemia

C) the inflammatory response

Which of the following is/are NOT a first line of defense? A) Skin B) Tears C) Saliva D) Fever E) Lysozyme F) A-E are all first line defenses

D) Fever

Regarding the neurotoxigenic disease caused by Clostridium botulinum, which of the following is not correct? A) It is typically due to improper sterilization of canned foods B) It blocks neurotransmitter release to muscles C) The causative agent is an anaerobe that produces endospores D) It causes spasmic paralysis, i.e, continual muscle contractions that cannot stop

D) It causes spasmic paralysis, i.e, continual muscle contractions that cannot stop

A bacteria such as Clostridium botulinum (produces botulism exotoxin) would beconsidered a/an: A) Opportunistic pathogen B) Commensal C) parasite D) Primary pathogen E) Mutualist

D) Primary pathogen

The toxin genes for both cholera toxin in Vibrio cholera and shiga toxin in Shigella, respectively, are unique in that the genes of each are acquired from a A) plasmid B) protozoan C) bacterial chromosome D) bacteriophage (i.e., bacterial virus) chromosome E) none of the above

D) bacteriophage (i.e., bacterial virus) chromosome

Which of the following should be free from microbes in a healthy individual? A) nose B) mouth C) skin D) cerebrospinal fluid E) gastrointestinal tract

D) cerebrospinal fluid

Which of the following is not an integral part of the inflammatory process? A) dilation of blood vessels B) release of histamines, bradykinin, and prostaglandins C) extravasation D) decrease in the permeability of blood vessels in the area E) release of cytokines to attract cells of the immune system

D) decrease in the permeability of blood vessels in the area

BONUS Commensals do not need virulence factors to survive on their host because: A) they are well adapted for their specific niche B) they do not breach the host barriers and immune system C) they do not normally cause disease D) two of A, B, and C are correct E) A, B, and C are all correct

E) A, B, and C are all correct

Which of the following statements among A-D is not accurate regarding complement? A) the effect of complement typically depends on activation of complement factor C3 B) complement is present in blood C) activated complement factors can combine to form pores in the plasma membrane of infecting cells and kill them D) complement is part of your innate immune system, but also works with the adaptive immune system E) A-D are all accurate statements regarding complement.

E) A-D are all accurate statements regarding complement.

Which of the following is not a characteristic of B cells? A) Memory B cells are responsible for the enhanced secondary antibody response B) They have antibodies on their surfaces C) Plasma B cells form and secrete antibodies D) B cells are incapable of directly killing pathogenic microbes E) A-D are all characteristics of B cells

E) A-D are all characteristics of B cells

Which of the following is not applicable to pathogenic strains of Staphylococcus aureus? A) It is a primary cause of skin infections B) Many strains are resistant to conventional penicillin-like antibiotics C) It can cause gastroenteritis due to food poisoning D) Toxic shock syndrome is attributable to this bacterium E) All are applicable to Staphylococcus aureus

E) All are applicable to Staphylococcus aureus

Which of the following pairs is matched correctly? A) Interferons: secreted by eukaryotic cells in response to intracellular infection, specifically viral infections. B) Toll-like receptors: bind with bacterial surface molecules and release chemicals that trigger host defenses C) Defensins: form channels in bacterial cytoplasmic membranes, ultimately killing the cell D) Complement: more effective against Gram-negative cells E) All are matched correctly.

E) All are matched correctly.

Which of the following does not contribute to the virulence of a pathogen? A) Toxins B) Capsule C) Fimbriae/pili D) Numbers of microorganisms that gain access to a host E) All contribute to the virulence of a pathogen

E) All contribute to the virulence of a pathogen

BONUS Which of the following bacterial types does not become an intracellular pathogen (either facultative or obligate) during the course of an infection? A) Chlamydia B) Salmonella C) Shigella D) Mycobacterium tuberculosis E) All the above can become an intracellular pathogen.

E) All the above can become an intracellular pathogen.

Which of the following among A-D is false regarding Streptococcus? A) There are no pathogenic types in the gamma-hemolytic group. B) They are Gram-positive round cells arranged in chains. C) The alpha-hemolytic types include agents that cause pneumonia and tooth decay. D) The beta-hemolytic types exhibit complete lysis of red blood cells on blood agar. E) None are false; A-D are all true statements

E) None are false; A-D are all true statements

Which is false among A-D regarding sexually transmitted diseases (STDs)? A) Since STD pathogens are susceptible to drying out, they require direct contact with mucous membranes for trans mission. B) Causative agent of syphilis is a spirochete, Treponema pallidum C) Diagnosis of gonorrhea: Gram-negative diplococci in males urethral discharge D) Tertiary syphilis: advanced stage of untreated disease; characterized by dementia and/or heart problems E) None are false; all are true statements.

E) None are false; all are true statements.

The phenomenon of membrane ruffling carried out by Shigella and other bacteria, is depicted in the above photograph. Which is true regarding this process? A) It is a type of phagocytosis, leading to death of the bacterium. B) It allows the bacteria to remain outside the host cell. C) It is induced by the binding of antibodies to the bacterium. D) It is caused by the release of exotoxin by the bacterium. E) None are true statements.

E) None are true statements.

Natural killer cells target: A) cells that have MHC I surface proteins B) bacterial cells that are coated with complement C) infected cells bound with antibody D) extracellular viruses E) None of the above

E) None of the above

Which is true of opsonization? A) It requires the presence of T cells B) It involves interferon C) It is a process specific for destroying virus-infected cells D) It only works on encapsulated bacteria E) None of the above are true

E) None of the above are true

Which pathogen:description pair is not correct? A) Giardia: protozoal pathogen that is transmitted in feces (to water) as a cyst form. B) Neisseria meningitidis: capsulated, central nervous system pathogen capable of crossing theblood-brain barrier C) Mycobacterium tuberculosis: slow-growing, acid fast bacterium that causes a chronic respiratory disease D) Streptococcus pyogenes: primary cause of sore throats and also causes flesh-eating disease(i.e., necrotizing fasciitis) E) Streptococcus mutans: primary cause of pneumonia among humans

E) Streptococcus mutans: primary cause of pneumonia among humans

Which of the following is a fomite? A) water B) droplets from a sneeze C) pus D) insects E) a hypodermic needle

E) a hypodermic needle

A woman falls and suffers a cut on her leg. The cut went through her skin and she is bleeding. Which of the following defense mechanisms will participate in eliminating contaminating microbes? A) mucociliary escalator (i.e., ciliated cells in trachea, lungs) B) normal skin flora C) acidic skin secretions D) lysozyme E) phagocytosis and the inflammatory response

E) phagocytosis and the inflammatory response

Antibody(s) that only bind antigen when bound to another cell type A) IgG B) IgA C) IgD D) IgE E) A and B F) C and D

F) C and D

Which is false? A) Parental route: via surgery, injection, or bite B) Invasins: virulence factor of intracellular pathogens C) Probably the easiest and most frequently traveled portal of entry: Respiratory tract D) Endotoxin: associated with gram negative pathogens E) Streptokinase: breaks down fibrin (blood clots) F) Fomite: vector transmission

F) Fomite: vector transmission