Biology · Science General

Disease Causative Agents

2,258 Questions

Disease causative agents questions test your understanding of viral, bacterial, and fungal infections, along with their transmission methods. These are common topics in general science sections of SSC and railways exams. Practice these questions to accurately identify disease pathogens and symptoms.

Viral diseasesFoodborne illnessesDisease transmission methodsExtrinsic disease factorsCommon pathogens

Disease Causative Agents Questions

Multiple choice

Which of the following is the odd one out?

  1. Malaria

  2. Typhoid

  3. Dengue fever

  4. Tuberculosis

  5. Cholera
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Tuberculosis is an air borne disease, while all the othes are insect borne diseases. Cholera is also an insect borne disease.

Multiple choice

Which of the following is not a part of Koch’s postulate?

  1. Bacteria may or may not cause disease in experimental animals.

  2. Bacteria should be isolated from the diseased animals.

  3. Bacteria should be cultivable outside the animal.

  4. Bacteria should be able to cause the same disease or condition when inoculated in another animal.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Koch’s postulates were first indicated by Henle but enumerated by Koch and they determine whether a microorganism is pathogenic or not.

Multiple choice

____________ are the most common pathogens responsible for nosocomial pneumonias in the ICU.

  1. Gram-positive organisms

  2. Gram-negative organisms

  3. Mycoplasma

  4. Virus infections
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Nosocomial infections are hospital-acquired infections, which develop in hospitalized patients. Streptococcus pyogenes was the most important causative organism in the ICU,  but due to antibiotic sensitivity, it is now hardly encountered.

Multiple choice

All of the following organisms are known to survive intracellularly except ______________.

  1. the Neisseria meningitides

  2. the Salmonella typhi

  3. the Streptococcus pyogenes

  4. the Legionella pneumophila
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Neisseria, salmonella typhi and legionella can survive intracellularly but not S.pyogenes.

  1. Neisseria meningitidis is found in spinal even inside leucocytes (intracellularly).
  2. Legionella can enter alveolar macrophages.
  3. Salmonella typhi can multiply within polymorphs, and hence can resist intracellular killing.
Multiple choice

Mycotic abscesses are due to ____________.

  1. bacterial infection

  2. fungal infection

  3. viral infection

  4. mixed infection
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Mycoses are fungal infections, e.g., superficial mycoses, systemic mycoses. Mycotic abscess-soft cystic mass with slight inflammation caused by hyaline and decataceous fungi and nocardia species.

Multiple choice

Which of the following option is correct regarding Virus?

  1. It is unicellular.

  2. It is acellular.

  3. It is prokaryotic.

  4. It is eukaryotic.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Viruses do not have a cellular organization. They are acellular. They have only one type of nucleic acid either DNA or RNA. They also do not have enzymes for protein and nucleic acid synthesis. So, they have characteristics of both living organisms and nonliving objects.

Multiple choice

Viruses that are present with oral manifestation are ______________.

  1. anthrax

  2. herpangina

  3. candiasis

  4. cryptococcosis
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Herpangia a.  It is caused by coxsackie virus. b.  It is related to intraoral lesions. c.  C/F – sore throat, cough, low grade fever, vesicles,  which rupture to form ulcers on anterior faucial pillars, hard and soft palate and posterior pharyngeal walls.

Multiple choice

Actinomycosis is caused by ______.

  1. virus

  2. bacteria

  3. fungus

  4. unknown factor
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
  1.  It is a chronic granulomatous infection caused by actinomyces israelli mainly.
    1. Actinomyces are true bacteria; however, they superficially resemble resemble fungi, and hence called ray fungus. Actinomyces are positive bacteria.
    2.  Actinomycosis is also called lumpy jaw.
Multiple choice

Which of the following is a pair of diseases caused by Gram-positive bacteria?

  1. Gonococcal urethritis and Hansen’s coccus spirilly

  2. Cholera and Botulism

  3. Hansen’s coccus spirilly and Listeriosis

  4. Gonococcal urethritis and Cholera

  5. Gonococcal urethritis and Listeriosis
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

This option is correct because Hansen’s coccus spirilly is a disease caused by a Gram-positive bacterium Mycobacterium tuberculosis and Listeriosis is a bacterial infection most commonly caused by Listeria monocytogenes (Gram-positive bacterium).

Multiple choice

Which of the following diseases are caused by Gram-positive spore-forming bacteria?

P. Typhoid Q. Lockjaw R. Cryptococcosis S. Anthrax

  1. P and Q

  2. P and R

  3. Q and R

  4. Q and S

  5. R and S
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

This option is correct because anthrax is an infectious disease caused by a Gram-positive, spore-forming rod-shaped bacterium Bacillus anthracis and lockjaw is an infectious disease caused by the anaerobic Gram-positive, spore-forming bacterium Clostridium tetani.