IMMUNOLOGY

1. A foreign substance when introduced into our body, it can stimulate immune response?

a-Antibody. b-Antigen. c-Hapten. d-Complement. e-Adjuvant.

2- B-lymphocyte:

a-Originated from thymus gland.

b-Constitutes about 70% of the total lymphocytes

c-Powerful antigen presenting cell.

d-One of innate immunity cells.

e-Has CD3 as a surface marker.

3- Anaphylaxis is:

a-Ig E mediated hypersensitivity reaction.

b-IgA mediated hypersensitivity reaction.

c-Cell mediated hypersensitivity reaction

d-Type III hypersensitivity reaction.

e-An autoimmune reaction.

4- The meeting step (component) in all complement pathways is:

a-C2. b-C5. c-C1. d-C4. e-C3.

5- The antibody which increased in primary immune response:

a-Ig M. b-Ig G c-Ig D. d-Ig E. e-Ig A.

6- The immune cell which plays an important role against cancer:

a-Basophil. b-Mast cell. c-T-helper cell. d-Natural killer cell. e-Dendritic cell.

7- HIV affects and decreases the count of

a-B-lymphocyte. b-Macrophage. c-Dendritic cell. d-Natural killer cell. e-T-helper cell.

8- MHC-II present in.

a-RBCs. b-Epithelial cells. c-Platelets. d-Immune competent cells. e-All nucleated cells.
9- A mechanism by which the tumor can escape immune surveillance?

a-Stimulation of phagocytosis

b-Stimulation of Th1

c-Decreased expression of MHC I on tumor cell

d-Suppression of NK cell

e-Suppression of mast cell

10- The starting point of activation of the classical pathway of complement?

a-Endotoxins b-Antigen with a specific antibody c-Mucopolysaccharides d-HIV e-Lectins

11- Interleukin 2 (IL-2) secreted by?

a-TH1 cell b-B-cell c-NK-cell d-TH 2 cell e-Mast cell

12- A graft between genetically different members of the same species is termed an:

a-Autograft b-Isograft c-Xenograft d-Allograft e-Syngeneic graft

13- Non-specific suppression of graft rejection can be achieved with:

a-Ricin A chain b-Anti-IL-5 c-Anti-NF kappa B d-Anti-CD34 e-Anti-CD3

14- Graft vs host disease often accompanies transplantation of:

a- Cartilage. b- Kidney. c- Bone marrow. c- Heart. e- Pancreas.

15- The very rapid response to a second allogeneic graft is:

a- Specific for antigens of the major histocompatibility complex (MHC)

b- Dependent on minor histocompatibility antigens.

c- Transferred by macrophages to a naive recipient.

d- Transferred by platelets.

e- Transferred by IgA.

16- Hyperacute graft rejection is caused by:

a- Preformed antibody. b- CD4 lymphocytes c- CD8 lymphocytes. d- Platelets.

e-Circulating immune complexes.
17- Cyclosporine is an immunosuppressive drug given to avoid transplant rejection which acts
by:

a- inhibition of T cells

b- inhibition of B cells

c- inhibition of immune system

d- inhibition of complement system

e- inhibition of NK cells

18- Minor histocompatibility antigens are:

a- The major rejection problem in MHC - mismatched renal transplantation

b- Of no consequence in allograft rejection

c- Critical targets during hyperacute rejection of organ allografts

d- Recognized as polymorphic donor peptides associated with self – MHC antigens

e- Encoded by genes located within the MHC

19- Components of innate immunity that are active against viral cells includes?

a. NK Cells b. Cytotoxic T cells c. B cells d. Memory B cells

20- The following immunoglobulin is not known to fix complement?

a. Ig E b. Ig M c. Ig A d. Ig G

21- Secondary immune response is mediated by?

a. Ig G b. Ig A c. Ig M d. Ig E

22- Killer and Helper cells are part of?

a. B cells b. T cells c. Monocytes d. Macrophage

23- Complement binding immunoglobin via the classical pathway is?

a. Ig G & Ig M b. IgG & Ig A c. IgG & Ig D d. Ig D & Ig E

24- The main antibody in saliva is

a. Ig G b. Ig A c. Ig M d. Ig E
25. One principal function of complement is to:

A. cross-link allergens

B. inactivate perforins

C. bind antibodies attached to cell surfaces and to lyse these cells

D. phagocytize antigens

26. Which of the following is a messenger that mediates the connection between the innate
and adaptive immune systems?

A- Complement components B- Vaccines C- T and B lymphocytes D- Cytokines

27. Which of the following is the one true statement about acute rejection.

A. Acute rejection is mediated by T lymphocytes.

B. Acute rejection is mediated by T and B lymphocytes.

C. Acute rejection is mediated by preformed cytotoxic antibodies.

D. Acute rejection most frequently occurs over months.

28. Name the part of a processed antigen that binds to the MHC molecule and is recognized by
T-cells.

A. Immunoglobulin. B. Agrotope. C. Epitope. D. Chaperone.

29. Naturally acquired active immunity would be most likely acquired through which of the
following processes?

A. vaccination B. drinking colostrum C. natural birth

D. Infection with disease-causing organism followed by recovery.

30. The specificity of an antibody is due to

A. its valence B. The heavy chains C. The Fc portion of the molecule D. The variable portion

31. The ability of the immune system to recognize self-antigens versus non-self-antigens is an
example of:

A. Specific immunity B. Tolerance C. Cell-mediated immunity D. Antigenic immunity

32. Name the cytokines which are released in response to virus infection?

A. Interferons C. Lymphokyne B. Monokynes D. Interleukins

33. Which of the following does not protect body surfaces:

a. Skin. b. Mucus c. Gastric acid. d. Gut microflora.

34. Upon encountering an appropriate MHC I on a virally infected host cell,

A. B cells rearrange cell-surface receptors.

B. CD8 + T cells undergo apoptosis.

C. cytotoxic T cells release granzymes.

E. Th0 cells differentiate into Th2 cells.

D. Th1 cells express IL-2 receptors.

35. A cytokine that promotes humoral immunity and is produced by T h 2 cells is a:

(A) INF-γ (B) IL-4 (C) IL-6 (D) IL-10 (E) IL-17

36. A cytokine that promotes cell-mediated immunity and is produced by Th 1 cells is a:

(A) INF-γ (B) IL-4 (C) IL-6 (D) IL-10 (E) IL-17
Bacteriology

1- Of the following bacterial components, which one exhibits the most antigenic variation?

(A) Capsule (B) Lipid A of endotoxin (C) Peptidoglycan (D) Ribosome (E) Spore

2- β-Lactamases are an important cause of antibiotic resistance. Which one of the following is
the most common site where β- lactamases are located?

(A) Attached to DNA in the nucleoid

(B) Attached to pili on the bacterial surface

(C) Free in the cytoplasm

(D) Within the capsule

(E) Within the periplasmic space

3- Mycoplasmas are bacterial cells that:

A. Fail to reproduce on artificial media

B. Have a rigid cell wall

C. Are resistant to penicillin

D. Stain well with Gram’s stain

4- The identification of bacteria by serologic tests is based on the presence of specific antigens.
Which of the following bacterial components is least likely to contain useful antigens?

a- Capsule b- Cell wall c- Flagella d- Ribosomes e- Pili

5- The cell wall of gram-positive bacteria may contribute to the development of septic shock.
Identify the component which is most associated with the induction of septic shock?

a- Capsular protein b- Endotoxin c- Peptidoglycan d- Phospholipid e- Teichoic acid

6- Bacterial cytoplasmic membrane is responsible for:

a- Respiration and energy production

b- Passive permeability

c- selective toxicity

d- shape of the cell

7- Each of the following statements concerning the mechanisms of resistance to antimicrobial
drugs is correct EXCEPT:

a- R factors are plasmids that carry the genes for enzymes that modify one or more drugs.

b- Resistance to some drugs is due to a chromosomal mutation that alters the receptor for the
drug.

c- Resistance to some drugs is due to transposon genes that code for enzymes which inactivate
the drugs.

d- Resistance genes are rarely transferred by conjugation

8- Which one of the following sets of properties of exotoxins and endotoxins is correctly
matched?

a- Exotoxins: polypeptides/endotoxins: lipopolysaccharide

b- Exotoxins: weakly antigenic/ endotoxins: highly antigenic

c- Exotoxins: produced only by gram-negative bacteria/endotoxins: produced only by gram-

positive bacteria

d- Exotoxins: weakly toxic per microgram/endotoxins: highly toxic per microgram

e- Exotoxins: toxoid vaccines are ineffective/ endotoxins: toxoid vaccines are effective

10- Which one of the following drugs inhibits bacterial nucleic acid synthesis by blocking the
production of tetrahydro folic acid?

(A) Ceftriaxone (B) Erythromycin (C) Metronidazole (D) Rifampin (E) Trimethoprim

11- The action of which of the following agents or processes on bacteria can be reversed?

A) A bactericidal agent B) A bacteriostatic agent C) A disinfectant

D) Autoclaving at 121°C for 15 minutes E) Dry heat at 160–170°C for 1 hour

12- Oral thrush is considered an example of:

a-allergy b-superinfection c-drug toxicity d-drug resistance

13- Septicemia is:

a. Bacteria in blood b. Toxin in blood c. Pus in blood

d. Multiplication of bacteria and toxins in blood

14- The initial step in the process of many bacterial infections is adherence of the organism to
mucous membranes. The bacterial component that mediates adherence is the:

(A) Lipid A (B) Nucleoid (C) Peptidoglycan (D) Pilus (E) Plasmid

15- Bacteria that cause nosocomial (hospital-acquired) infections often produce extracellular
substances that allow them to stick firmly to medical devices, such as intravenous catheters.
Which one of the following is the name of this extracellular substance?

(A) Axial filament (B) Endotoxin (C) Flagella (D) Glycocalyx (E) Porin

16- The emergence of antibiotic-resistant bacteria, especially in enteric gram-negative rods, is a

medically important phenomenon. This most commonly occurs by a process that involves a sex
pilus and the subsequent transfer of plasmids carrying one or more transposons. Which one of
the following is the name that best describes this process?

a- Conjugation b- Transduction c- Transformation d- Translocation e- Transposition

17- The most accurate statement regarding transposons is:

(A)They encode enzymes that degrade the ends of the bacterial chromosome.

(B) They are short sequences of DNA that often encode enzymes that mediate antibiotic
resistance.

(C) They are short sequences of RNA that silence specific regulatory genes.

(D) They are a family of transfer RNA's that enhance mutations at hot spots in the bacterial
genome.

18- Viruses enter cells by adsorbing to specific sites on the outer membrane of cells. Each of the
following statements regarding this event is correct EXCEPT:

(A) The interaction determines the specific target organs for infection.

(B) The interaction determines whether the purified genome of a virus is infectious.

(C) The interaction can be prevented by neutralizing antibody.

(D) If the sites are occupied, interference with virus infection occurs.

19- Many viruses mature by budding through the outer membrane of the host cell. Each of the
following statements regarding these viruses is correct EXCEPT:

(A) Some of these viruses cause multinucleated giant cell formation.

(B) Some new viral antigens appear on the surface of the host cell.
(C) Some of these viruses contain host cell lipids.

(D) Some of these viruses do not have an envelope.

20- Which one of the following statements concerning interferons is LEAST accurate?

(A) Interferons are proteins that influence host defenses in many ways, one of which is the
induction of an antiviral state.

(B) Interferons are synthesized only by virus-infected cells.

(C) Interferons inhibit a broad range of viruses, not just the virus that induced the interferon.

(D) Interferons induce the synthesis of a ribonuclease that degrades viral mRNA.

21- Which one of the following best describes the action of oseltamivir?

(A) Inhibits reverse transcriptase

(B) Inhibits the RNA-dependent RNA polymerase in the virion

(C) Inhibits the DNA-dependent RNA polymerase in the infected cell

(D) Inhibits viral protein synthesis by binding to the 60S ribosomal subunit

(E) Inhibits the neuraminidase required for release of virus from the infected cell

22- The term “eclipse period” refers to:

A) the time between entry of the parental virus into the cell and the appearance of the first
progeny virion.

B) the period between epidemic outbreaks of diseases that occur in a cyclic pattern.

C) the time between exposure of an individual to a virus and the first appearance of disease.

D) the time between infection of cell by a virus and the appearance of cytopathic effects.

E) the period between recurrences of disease in individuals with latent virus infections.

23- Interferons are an important part of the host defense against viral infections. What is
interferon’s principal mode of action?

A) It coats viral particles and blocks their attachment to cells.

B) It induces synthesis of cellular proteins that inhibit translation.

C) It inhibits viral reverse transcriptase enzyme.

D) It is present in the serum of healthy individuals, providing a viral surveillance role.

E) It protects the virus-infected cell that produced it from cell death.

24- An outbreak of postsurgical wound infections caused by Staphylococcus aureus has

occurred in the hospital. The infection control team was asked to determine whether the
organism could be carried by one of the operating room personnel. Using your knowledge of
normal flora, which one of the following body sites is the most likely location for this organism?

(A) Colon (B) Gingival crevice (C) Mouth (D) Nose (E) Throat

26- Your patient has subacute bacterial endocarditis caused by a member of the viridans group
of streptococci. Which one of the following sites is MOST likely to be the source of the
organism?

(A) Skin (B) Colon (C) Oropharynx (D) Urethra

27- A micron (micrometer, µm) is the unit of measurement used in bacteriology. 1 micron (µm)
equals ……… millimeter (mm).

a- 1/1000 b- 1/10000 c- 1/100000 d- 1/1000000

28- In bacterial growth curve, which phase corresponds to the period of clinical signs and
symptoms of the disease

a- Lag phase b- Logarithmic phase c- stationary phase d- decline phase

29- Components of the chain of infection include all of the following EXCEPT:

a. Portal of entry. b. Portal of exit. c. Nutrients of the organism. d. Source

VIROLOGY

1- General properties of viruses do not include:

a- They are obligate intracellular parasites.

b- They contain a single type of nucleic acid

c- The virus particle consists of a nucleic acid genome packaged into a protein coat, which itself
is sometimes enclosed by an envelope.

d- They replicate by the assembly of the individual components and do not replicate by division,
such as binary fission.

e- They are susceptible to the action of antibiotics

2- Which of the following phase determines the specificity of the virus?

a) Uncoating b) Release c) Attachment d) Penetration

3- Which of the following is the most common capsid shape of the virus?

a) Cone b) Icosahedron c) Cube d) Rod

4- Which of the following is not the criteria for the classification of virus host interactions?

a) Signs and symptoms b) Duration of infection

c) Production of infectious progeny d) Size of the virus

5- Which of the following viruses are best known for latent infections?

a) Herpesvirus b) Poliovirus c) HIV d) Rhinovirus

6- Which of the following genus mumps virus belongs to?

a) Rubula virus b) Ebola virus c) Aali virus d) Dinorna virus

7- Which of the following method is used for the detection of antigen?

a) EIA b) PCR c) Dot blot hybridization d) Boiling lysis

8- Which of the following antiviral drug is used to treat influenza A1

a) Dextran sulfate b) Amantadine c) Ganciclovir d) Cidofovir

9- Which of the following is not used in the HIV treatment?

a) Delavirdine b) Zidovudine c) Rimantadine d) Stavudine

10- Which of the following is used to treat poxvirus?

a) Zalcitabine b) Cidofovir c) Penciclovir d) Zanamivir

11- Which of the following cannot be treated by antiviral drugs?

a) Tuberculosis b) Smallpox c) Hepatitis d) Warts

12- Influenza virus belongs to the family _____________:

a) Papoviridae b) Orthomyxoviridae c) Parvoviridae d) Retroviridae

13- The variation of which of the following causes influenza despite vaccines available?

a) Hemagglutinin b) Hyaluronidase c) Pepsin d) Elastase

14- Which of the following influenza virus contain seven RNA segments?

a) Influenza A b) Influenza B c) Influenza C d) Influenza D

15- Viruses contain ___________ as their genome:

a) dsDNA b) ssDNA c) dsRNA d) ssRNA e. all of the former

16- The filoviruses are classified as __________________ pathogens.

a) Biosafety level 4 b) Biosafety level c)1 Biosafety level 3 d) Biosafety level 2

17- Which of the following is the disease of the skin caused by papillomaviruses?

a) Flat wart b) Epithelial hyperplasia c) Oral papilloma d) Genital malignancies

18- Which of the following causes Kaposi’s sarcoma?

a) EBV b) HCV c) HHV d) HPV

19- Adult T-cell Leukemia (ATL) is a tumor of ___________

a) CD8 b) CD4 c) CD10 d) CD16

20- Which of the following is used to treat rubella?

a) ZMR b) MMR c) RMR d) RAR

21- Lamivudine is used in treatment of?

a) CMV b) EBV c) HAV d) HBV

22- Which of the following therapy is used to halt HIV replication?

a) Gene therapy b) Chemotherapy c) HAART therapy d) Physiotherapy

23- HIV is a member of __________ family.

a) retroviridae b) arenaviridae c) filoviridae d) flaviviridae

24- HIV is a:

a) Diploid b) haploid c) ssDNA d) dsDNA

25- Which of the following infection results in the continuous production of viruses?

a) Persistent b) Abortive c) Null d) Transforming

26- Which of the following infection causes a change in the properties of the cell?

a) Latent b) Abortive c) Transforming d) Null

27- Which infection causes a reduction in the total yield of virus particles?

a) Null b) Transforming c) Abortive d) Cytopathogenic

28- Which of the following causes the paralysis of respiratory and pharyngeal muscles?

a) Bulbar poliomyelitis b) Asthma c) Polyradiculitis d) COPD

29- Which of the following is called Guillain-Barre syndrome?

a) Asthma b) Polyradiculitis c) Heart failure d) Paralysis

30- Which of the following virus may spread due to lack of good hygienic practice and
consumption of contaminated water?

a) Hepatitis B and D b) Human papillomavirus c) Hepatitis A and E d) Zika virus

31- …………….. are the only viruses that produce genome DNA by reverse transcription with
mRNA as the template.

a. Hepadnaviruses b. Retroviruses c. Influenza viruses d. SARS viruses

32-………… virus is a defective virus?

a. Influenza b. SARS c. Marburg d. Hepatitis D

33- Transmission of hepatitis G virus is d. SARS viruses

A. Parenterally B. Sexually C. Both (a) and (b) D. None of these

34- Oral hairy leukoplakia is a condition triggered by?

a. HIV b. HBV c. Epstein-Barr virus d. HAV