Clinical Bacteriology 3rd Semester Bs(Hons) MLT

MCQS: Choose the best answer

1. Salmonella Typhi which lives in the human colon infects_________________ system of

the human.
a. Central nervous system
b. GIT
c. Reticuloendothelial System
d. Respiratory
e. Cardiovascular system
2. The infectious dose of Shigella is _____________
a. Increased
b. Low
c. Moderate
d. High
e. Very High
3. Helicobacter Pylori synthesize urease which produces _____________ that damages
gastric mucosa.
a. NH3
b. H2S
c. CO2
d. Hcl
4. ____________ of Klebsiella Pneumonie causes fever and shock associated with sepsis.
a. Endotoxin
b. Exotoxin
c. Capsule
d. Spores
e. Granules
5. A patient is suffering from Upper respiratory tract, Microscopic examination of smear
shows small gram-negative (coccobacillary) rods, Latex agglutination can also be seen.
Which one is the most accurate organism?
a. Escherichia Coli
 b. Haemophilus Influenza.
c. Vibrio cholerae
d. Pseudomonas Aeruginosa
e. Mycobacterium tuberculosis
6. Haemophilus Influenza can cause many diseases such as sinusitis, otitis, Pneumonia but
in most cases it cause__________________
a. Endocarditis
b. Meningititis
c. Epiglotitis
d. Pancreatitis
7. Niesseria are gram-negative cocci which contains ___________ in their outer membrane
a. Endotoxin
b. Lipopolysaccharide
c. Exotoxin
d. None of the above
8. Gonococci like meningococci cause disease only in
a. Male
b. Female
c. Children
d. Animals
e. Human
9. Which of the following is true about endotoxin
a. They cause throat infection
b. They cause acidity
c. They cause fever shock and other pathological changes.
d. They cause osteoarthritis
10. Which of the following is not true about Neisseria Meningitis?
a. The organisms are transmitted via respiratory droplet.
b. Genital tract infection are the most common infection caused N.Meningitis.
c. They colonize in the membranes of the nasophyrnx
d. The carriage rate can be high as 35% in people
11. All are the medically important genera of Gram-positive rods except
a. Bacilllus
b. Clostridium
c. Corynebacterium Diphtheriae
d. Syphilis
e. Escherichia coli
12. Which one is true about bacillus Anthracis
 a. They Can cause anthrax disease
b. They are Non motile
c. They are Motile
d. Large gram-positve rod with square
e. Its antiphagocytic capsule is composed of D-Glutamate
13. Tetanus is cause by _______________ bacteria.
a. Colistridium Tetani
b. Colistridium Botilinum
c. Colistridium Difficile
d. Colistridium Perfirngens
e. Listeria
14. Gas Gangrene and food poisning are caused by __________ bacteria
a. Colistridium Perfringens
b. Colistridium tetani
c. Colistriduim Botilinum
d. Colistriduim Difficile
e. Colistridium Solmonella
15. What is true about Mycobacterium tuberculosis which cause Tuberculosis
a. Aerobic
b. Acid fast rod
c. High lipid content
d. All of the above
16. Which media is used for Mycobacteria
a. Blood agar
b. Chocolate agar
c. Lowenstein-Gensen media
d. Macconkey
17. Mycobacterium is transmitted from person to person by which route.
a. Direct contact
b. Respiratory Aerosols
c. Sexually
d. Food
18. Chlamydiae and Rickettsiae are
a. Obligate Anaerobic Bacteria
b. Obligate Aerobic Bacteria
c. Obligate intracellular parasites
d. Facultative anaerobe
19. Regarding Claymdiae which of the following is most accurate
 a. Life long immunity usually follows an episode of disease caused by hese
organism
b. The reservoir host for the 3 specis pof Claymedia that cause human infection
c. Their life cycle consist of bodies outside of cells and reticulate bodies within cell
d. They can only replicate within cells because they lack the ribosome to
synthesis their protiens
20. Which of the following bacterial species infect primarily epithelial cell of mucous
membrane of the lung
a. M.Leprae
b. M.tuberclosis
c. Chlamydiae
d. Borrelia
21. Which one of the following disease is not caused by Staph. Aureus?
a. Abscesses
b. Scalded skin syndrome
c. Kawasaki syndrome
d. Urinary tract Infection
e. Meningitis
22. S. epidermidis cause ___________
a. Food poisoning
b. Urinary Tract infection
c. Stomach infection
d. Pulmonary infection
23. Yellow or Golden colonies on blood agar indicate the growth of
a. Staph. Aureus
b. Staph. Epidermidis
c. Streptococcus pyogenes
d. Streptococcus pneumoniae
24. Gram-negative, “kidney bean” diplococci which cause meningitis is ferments
a. Lactose
b. Glucose
c. Glactose
d. Maltose
25. Which of the following disease is not caused by Staph. Epidermidis
a. Endocarditis
b. Neonatal sepsis
c. Cerebrospinal fluid shunt infection
d. Diphtheria
26. E. coli ferment
a. Lactose
b. Glucose
c. Glactose
d. Maltose
27. Bacterial surface structures that show antigenic diversity include each of the following
Except
a. Pili
b. Capsule
c. Flagella
d. Peptidoglycan
28. Nosocomial Infection also called Hospital acquired infection are commonly caused by
a. Pneumococcus
b. Escherichia coli
c. Neisseria meningitidis
d. Staphlococcus Aureus

29. Mycoplasmas are the smallest free living microorganisms which have lack of cell wall the
diameter of this organism is about
a. 0.2 micrometer
b. 0.4micrometer
c. 0.3micrometer
d. 0.5micrometer
30. In the laboratory diagnosis of mycoplasma Pneumoniae is not made usually by culturing
sputum samples it takes_______ days for colonies to appear on special media
a. 5 days
b. 7 days
c. 9 days
d. 11 days
e. 2 days
31. Each of the following statements concerning pneumonia caused by Mycoplasma
pneumonia is correct except
a. Pneumoniacaused by M>pneumonia is associated with rise in the titer of cold
aglglutinins
b. Pneumonia caused by M. Pneumonia occurs primarly I immunocompetant
individuals.
c. Pneumonia caused by M.pneumonia is an atypical pneumonia
d. M.Pneumonia cannot be cultured in Vitro it has no cell wall
 32. T. pallidum is transmitted from spirochete containing lesions of skins or mucous
membrane through
a. Gentilia, mouth, rectum
b. lungs, intestines
c. Lungs, Stomach
d. Intestine, stomach
33. Borrelia species are irregular loosely coiled and they are transmitted through
a. Soils
b. Water
c. Respiratory drops
d. Animals
e. Arthropods
34. Regarding syphilis which one of the following is the most accurate
a. The characteristics lesion of primarly syphilis is a painful vesicle on the genitals
b. In secondary syphilis the number of organism is low so the chance of
transmitting the disease to other is low
c. In secondary syphilis both the rapid plasma regin (RPR) and the florescent
treponomal antibody absorbed(FTA-ABS) tests are usually positive
d. The antibody titer in the (FTA-ABS) test typically declines when patient has been
treated adequately.

Q No 35 : : Flash pasteurization can be done by exposing the Milk to heat at

(A) 62 °C for 30 min
(B) 72 °C for 15 mins

(C) 72 °C for 15 sec

(D) 70 °C for 15 mins

Q No 36 : Sterilization is the killing of all form of Microorganism including bacterial spores,can

be done by Autoclaving which consists of

(A) Exposure to steam at 121 °C

(B) Under a pressure of 15 lb/in*2

(C) For the time of 15 mins

(D) All of the above

Q No 37: Killing of Microorganism can be done by Chemical agents which mechanism is

(A) Disruption of cell membrane

(B) Modification of protein

(C) Modification of Nucleic acid

(D) All of the above

Q No 38: _______ is used as disinfectant to purify the water supply and treatment of
swimming pools
(A) Iodine
(B) Benzene

(C) Chlorine

(D) Mercury and Silver

Q No 39: World Health Organization (WHO) has classified Micro-organisms into four Risk
Groups Which one is high risk group?

(A) RISK GROUP I

(B) RISK GROUP II

(C) RISK GROUP III

(D) RISK GROUP IV

Q No 40: Ultraviolet light and X-radiation is often used to sterilize heat-sensitive items, that
kills by

(A) Damaging of DNA

(B) Damaging of RNA

(C) Filtration

(D) Damaging of Cell membrane.

Q No 41. Bacteria, fungi (yeasts and molds), viruses, and protozoa are important causes of
human disease. Which one of the following microbes contains either DNA or RNA but not
both?
(A) Bacteria
(B) Molds
(C) Protozoa
(D) Viruses
(E) Yeasts

Q No 42: Which one of the following contains DNA that is not surrounded by a nuclear
membrane?
(A) Bacteria
(B) Molds
(C) Protozoa
(D) Yeasts

Q No 43: The degree of pathogenicity in a microorganism is called

(A) Lethal dose
(B) Infectious dose
(C) Pathogenicity
(D) Virulence
Q No 44: Any deviation from a condition of good health and well-being is called
(A) Disease
(B) Infectious Disease
(C) Pathogenicity
(D) Virulence

Q No 45: Mycobacterium tuberculosis stains well with the acid-fast stain, but not with the
Gram stain. Which one of the following is the most likely reason for this
observation?
(A) It has a large number of pili that absorb the purple dye.
(B) It has a large amount of lipid that prevents entry of the purple dye.
(C) It has a very thin cell wall that does not retain the purple dye.
(D) It is too thin to be seen in the Gram stain.
Q No 46: Some bacteria are obligate anaerobes. Which of the following statements best
explains this phenomenon?
(A) They can produce energy both by fermentation (i.e., glycolysis) and by
respiration using the Krebs cycle and cytochromes.
(B) They cannot produce their own ATP.
(C) They do not form spores.
(D) They lack superoxide dismutase and catalase.

Q No 47: The colon is the site of the largest number of normal flora bacteria. Which one of
the following bacteria is found in the greatest number in the colon?

(A) Bacteroides fragilis

(B) Clostridium perfringens
(C) Enterococcus faecalis
(D) Escherichia coli

Q No 48: The cells involved with pyogenic inflammation are mainly neutrophils, whereas
the cells involved with granulomatous inflammation are mainly macrophages and
helper T cells. Infection by which one of the following bacteria is most likely to
elicit granulomatous inflammation?
(A) Escherichia coli
(B) Mycobacterium tuberculosis
(C) Neisseria gonorrhoeae
(D) Staphylococcus aureus

Q No 49: Which one of the following chemicals is used to sterilize heat-sensitive materials,
such as surgical instruments, in the hospital?
(A) Benzalkonium chloride
(B) Cresol (Lysol)
(C) Ethylene oxide
(D) Tincture of iodine

Q No 50: Which of the following is not correct

(A) Eukaryotic cells contain organelles, such as mitochondria and lysosomes
(B) prokaryotes contain organelles and larger (80S) ribosomes.
(C) Bacteria reproduce by binary fission, whereas eukaryotic cells reproduce by mitosis.
(D) Normal flora are the permanent residents of the body.

Q No 51: In the process of studying how bacteria cause disease, it was found that a rare
mutant of a pathogenic strain failed to form a capsule. Which one of the following
statements is the most accurate in regard to this unencapsulated mutant strain?
(A) It was nonpathogenic primarily because it was easily phagocytized.
(B) It was nonpathogenic primarily because it could not invade tissue.
(C) It was nonpathogenic primarily because it could only grow anaerobically.
(D) It was highly pathogenic because it could secrete larger amounts of exotoxin.

Q No 52. A disease condition caused by the presence or growth of infectious microorganisms

or parasites
A) Disease
(B) Infectious Disease

(C) Pathogenicity

(D) Virulence

Q No 53. The ability of a microbe to cause disease is called

(A) illness
(B) Recovery
(C) Pathogenicity
(D) Virulence
Q No 54: In the Gram stain procedure, bacteria are exposed to 95% alcohol or to an
acetone/alcohol mixture. The purpose of this step is:
(A) To adhere the cells to the slide
(B) To retain the purple dye within all the bacteria
(C) To disrupt the outer cell membrane so the purple dye can leave the bacteria
(D) To facilitate the entry of the purple dye into the gram-negative cells

Q No 55. An infection characterized by sudden onset, rapid progression, and often with
severe symptoms

(A) Sub clinical Infection

(B) Opportunistic Infection

(C) Acute Infection

(D) Chronic Infection

Q No 56: An infection characterized by delayed onset and slow progression
(A) Sub clinical Infection
(B) Opportunistic Infection

(C) Acute Infection

(D) Chronic Infection

Q No 57: An infection with few or no obvious symptoms

(A) Sub clinical Infection
(B) Opportunistic Infection

(C) Acute Infection

(D) Chronic Infection

Q No 58. An infection that develops in an individual who is already infected with a different
pathogen
(A) Primary Infection
(B) Secondary infection

(C) Opportunistic Infection

(D) Localized Infection

Q No 59. An infection caused by microorganisms that are commonly found in the host’s
environment(Normal Flora) and affect immunocompromised individual
(A) Chronic Infection
(B) Localized Infection

(C) Opportunistic Infection

(D) Systematic Infection

Q No 60. What is true about “Systemic Infection”

(A) An infection that develop only in an individual who is immunocompromised.
(B) An infection that develops in an individual who is already infected with a different pathogen

(C) An infection that is restricted to a specific location or region within the body of the host

(D) An infection that has spread to several regions or areas in the body of the host

Q No 61. Presence of an infectious agent in the bloodstream is called

(A) Anemia
(B) Septicemia

(C) Bacteremia
(D) Inflammation

Q No 62. Which of the following is true regarding inflammation?

(A) Inflammation of the pharynx is called Pharyngitis

(B) Inflammation of the heart chambers is called Endocarditis

(C) Inflammation of the gastointestinal tract is called Gastroenteritis

(D) All of the above

Q No 63. The study of the transmission of disease

(A) Epidemiology
(B) Biostatistics

(C) Analytic report

(D) Entamology

Q No 64. A disease that can be transmitted from animal source is called

(A) Vector disease
(B) Communicable Disease
(C) Noncommunicable Disease
(D) Zoonotic disease

Q No 65: Which of the following is true about Communicable Disease

(A) A disease that is not transmitted from one individual to another
(B) A disease that can be transmitted from animal source

(C) A disease that can be transmitted from one individual to another

(D) A disease that can be transmitted via vector

Q No 66 : A disease condition that is normally occur at a persistent, usually low level in

certain geographical area.
(A) Endemic Disease
(B) Epidemic Disease

(C) Pandemic Disease

(D) Inapparent Disease

Q No 67: A disease condition that occur at a much higher rate then usual is called
(A) Endemic Disease

(B) Epidemic Disease

(C) Pandemic Disease

(D) Unapparent Disease

Q No 68: A disease that spread rapidly over large area of the globe

(A) Endemic Disease

(B) Epidemic Disease

(C) Pandemic Disease

(D) Inapparent Disease

Q No 69: Endotoxins are

(A) lipopolysaccharide (LPS) located in outer membrane only of gram-negative bacteria

(B) lipopolysaccharide (LPS) located in outer membrane only of gram-positive bacteria

(C) lipopolysaccharide secreted by both gram positive and gram negative bacteria

(D) polypeptides secreted by both gram positive and gram negative bacteria

Q No 70: Exotoxins are

(A) polypeptides (LPS) located in outer membrane only of gram-negative bacteria

(B) polypeptides (LPS) located in outer membrane only of gram-positive bacteria
(C) lipopolysaccharide secreted by both gram positive and gram negative bacteria

(D) polypeptides secreted by both gram positive and gram negative bacteria

Q No 71: Members of the normal flora have

(A) less-virulent
(B) cause disease in immunocompromised patient

(C) They constitute a protective host defense mechanism

(D) All of the above

Q No 72: Virulence is a quantitative measure of pathogenicity and is measured by the number

of organisms required to cause disease, The 50% infectious dose (ID50) is:

(A) the number of organism needed to kill half the host

(B) the number of organism needed to cause infection in half the host

(C) Vaccine that protect 50 % of polpulation

(D) Vaccine that kill 50% of infectious agent

Q No 73: which of the following is true about endotoxin

(A) High toxicity
(B) Greater antigenicity

(C) Poorly antigenicity

(D) Toxoids used as vaccines

Q No 74 : Human disease for which animals are the reservoir are called

(A) Animal disease

(B) Disease via Direct contact

(C) Indirect via Vector

(D) Zoonoses

Q No 75 : U.T.I, Neonatal Meningitis and Traveler’s Diarrhea are the disease commonly caused
be

(A) Pneumococcus

(B) Escherichia coli

(C)Neisseria meningitidis

(D)Staphlococcus Aureus

Answer key clinical Bacteriology

1 C 11 E 21 E 31 D 41 D 51 A 61 B 71 D
2 B 12 C 22 B 32 A 42 A 52 B 62 D 72 B
3 A 13 A 23 A 33 E 43 D 53 C 63 A 73 C
4 A 14 A 24 D 34 C 44 A 54 C 64 D 74 D
5 B 15 D 25 D 35 C 45 B 55 C 65 C 75 B
6 B 16 C 26 A 36 D 46 D 56 D 66 A
7 A 17 B 27 D 37 D 47 A 57 A 67 B
8 E 18 C 28 D 38 C 48 B 58 B 68 C
9 C 19 D 29 C 39 B 49 C 59 C 69 A
10 B 20 C 30 B 40 A 50 B 60 D 70 D