Question 1

The characteristic fever in Dengue Virus is characterized as?

Accepted Answer

Answer reason: Dengue fever classically shows a saddleback pattern with two febrile peaks separated by brief defervescence, i.e., a biphasic fever.

Question 2

Human Papillomaviruses infect?

Accepted Answer

Answer reason: HPV targets the basal layer of stratified squamous epithelium, entering through microabrasions; it does not infect myocardium or bone marrow.

Question 3

During which phase of growth of Penicillium chrysogenum maximum antibiotic production takes place?

Accepted Answer

Answer reason: Penicillin is a secondary metabolite produced mainly during the idiophase (stationary phase) that follows active growth, i.e., the second phase.

Question 4

Fermentation medium for oxytetracyclin (terramycin) consist of?

Accepted Answer

Answer reason: Standard industrial medium for oxytetracycline (Streptomyces rimosus) uses corn steep liquor, starch as carbon source, ammonium sulfate, sodium chloride, and CaCO3 for buffering—matching option A.

Question 5

Media composition for the production of streptomycin is?

Accepted Answer

Answer reason: Standard streptomycin fermentation by Streptomyces uses soybean meal, glucose, peptone, malt extract with calcium carbonate as a buffering agent; thus the medium with calcium carbonate is correct.

Question 6

Antibiotics are typically produced in fed batch reactors because?

Accepted Answer

Answer reason: Antibiotics are secondary metabolites produced best in late growth/early stationary phase; fed-batch permits growth limitation and timed precursor feeding while reducing toxicity from precursors. Therefore all statements are true.

Question 7

Which of the following event occurs during third phase of growth of P chrysogenum?

Accepted Answer

Answer reason: During the late/third phase of Penicillium chrysogenum fermentation, penicillin accumulation continues, mycelial autolysis begins, and deamination reactions release ammonia causing a slight rise in pH. Thus all listed events occur.

Question 8

Which of the following changes occur during first phase of growth of Penicillium chrysogenum?

Accepted Answer

Answer reason: During the initial (trophophase) of penicillin fermentation, Penicillium chrysogenum rapidly forms mycelia, utilizes lactic acid from corn steep liquor at a high rate, and releases ammonia into the medium from nitrogen metabolism; therefore all listed changes occur.

Question 9

The nurse knows that the highest concentration of HIV virus in infected patients is in?

Accepted Answer

Answer reason: HIV is present in varying concentrations across body fluids. Blood carries the highest viral load and represents the greatest transmission risk. Semen and CSF contain virus but at lower concentrations. Saliva contains minimal virus and is not considered a transmission source.

Question 10

What is the cell wall of fungi made up of?

Accepted Answer

Answer reason: Fungal cell walls are primarily composed of chitin and beta-glucans; not cellulose (plants) or murein/peptidoglycan (bacteria).

Question 11

Which of the following bacteria are classified as Gram-positive rods?

Accepted Answer

Answer reason: Clostridium species are Gram-positive anaerobic bacilli. Pseudomonas is a Gram-negative rod, and Neisseria and Moraxella are Gram-negative diplococci.

Question 12

What is the bacterial cell wall made of?

Accepted Answer

Answer reason: Bacterial cell walls are composed of peptidoglycan (also called murein), a polymer of sugar units cross‑linked by short peptide chains; thus all statements describe the same material.

Question 13

Which disease is characterized by a specific appearance?

Accepted Answer

Answer reason: Diphtheria classically shows a gray pseudomembrane in the throat and a "bull-neck" appearance, a distinctive clinical look. Tetanus and polio lack such a characteristic visible appearance.

Question 14

Candidiasis is caused by which type of organism?

Accepted Answer

Answer reason: Candidiasis is an infection by Candida species, which are yeasts (fungi).

Question 15

Which of the following diseases is caused by a virus?

Accepted Answer

Answer reason: Measles is caused by the measles virus (a paramyxovirus). Cholera (Vibrio cholerae), tetanus (Clostridium tetani), and anthrax (Bacillus anthracis) are bacterial diseases.

Question 16

Malaria is caused by which type of organism?

Accepted Answer

Answer reason: Malaria is caused by Plasmodium species, which are protozoan parasites transmitted by Anopheles mosquitoes.

Question 17

Which hepatitis virus is mainly transmitted through contaminated water?

Accepted Answer

Answer reason: Hepatitis A is spread primarily via the fecal–oral route, often through contaminated food or water, whereas hepatitis B, C, and D are spread mainly through blood and body fluids.

Question 18

Which infection is correctly identified as HPV among the options: (A) HPV, (B) Rhabdo, (C) HIV, (D) Herpes Zoster?

Accepted Answer

Answer reason: HPV stands for human papillomavirus; among the choices, only option A explicitly names HPV. HIV and Herpes zoster are different viruses, and 'Rhabdo' is not HPV.

Question 19

Which disease is produced when a Clostridium organism enters a wound and produces a toxin causing crepitus?

Accepted Answer

Answer reason: Gas gangrene, typically caused by Clostridium perfringens, produces exotoxins and gas in tissues leading to crepitus. Botulism and tetanus are neurotoxin-mediated illnesses without tissue crepitus; anthrax is due to Bacillus anthracis.

Question 20

Which of the following is not a communicable disease?

Accepted Answer

Answer reason: Polio, diphtheria, and hepatitis are infectious diseases transmitted person-to-person, whereas peptic ulcer is generally considered a non-communicable condition.

Question 21

What disease is caused by the female Anopheles mosquito?

Accepted Answer

Answer reason: Female Anopheles mosquitoes transmit Plasmodium parasites that cause malaria; typhoid is fecal-oral Salmonella infection, headache is a symptom, and appendix is an organ.

Question 22

Which of the following infections are sexually transmitted?

Accepted Answer

Answer reason: All listed conditions—HIV, herpes (HSV), syphilis, and chlamydia—are sexually transmitted infections.

Question 23

A client is admitted with suspected Legionnaires' disease. Which factor increases the risk of developing Legionnaires' disease?

Accepted Answer

Answer reason: Corticosteroid therapy causes immunosuppression, increasing susceptibility to Legionella pneumonia. The other options are not established risk factors.

Question 24

After several hospitalizations for respiratory ailments, a 6-month-old has been diagnosed as having HIV. The infant's respiratory ailments were most likely due to?

Accepted Answer

Answer reason: Pneumocystis (jirovecii/carinii) is the most common cause of severe respiratory illness in HIV-infected infants, leading to pneumonia early in life.

Question 25

Tuberculosis is a ______ disease?

Accepted Answer

Answer reason: Tuberculosis is caused by Mycobacterium tuberculosis and spreads person-to-person via airborne droplets, making it a communicable infectious disease.

Question 26

Which of the following organisms is the most common cause of early onset neonatal conjunctivitis?

Accepted Answer

Answer reason: Chlamydia trachomatis is the most common cause of neonatal conjunctivitis; it typically presents in the first 1–2 weeks of life. Other listed organisms are not common causes.

Question 27

What is the causative organism for peptic ulcer?

Accepted Answer

Answer reason: Helicobacter pylori colonizes the gastric mucosa and is the primary infectious cause of peptic ulcer disease; the other listed bacteria are not typical causes.

Question 28

German measles is also known as?

Accepted Answer

Answer reason: German measles is the common name for rubella; the other options are different infections (HSV, mumps, and pertussis).

Question 29

What is the incubation period of mumps?

Accepted Answer

Answer reason: Mumps typically has an incubation period of about 16–18 days (range 12–25 days); 18 days is the best single answer.

Question 30

Which one of the following diseases cannot be cured by taking antibiotics?

Accepted Answer

Answer reason: Plague, leprosy, and whooping cough are bacterial infections treatable with antibiotics, whereas amoebiasis is a protozoal infection requiring anti-amoebic agents (e.g., metronidazole), not standard antibiotics.

Question 31

What is the term used to refer to a rod-shaped bacterium?

Accepted Answer

Answer reason: Rod-shaped bacteria are called bacilli; cocci are spherical, spirilla are spiral, and vibrio are comma-shaped.

Question 32

Which bacteria causes pneumonia?

Accepted Answer

Answer reason: The classic bacterial cause of community‑acquired pneumonia is Streptococcus pneumoniae, a Gram-positive diplococcus; hence 'diplococci' identifies the typical causative organism. Pneumoconiosis is not an infection, and the other options are nonspecific.

Question 33

Which of the following is classified as a bacterial sexually transmitted infection (STI)?

Accepted Answer

Answer reason: Chlamydia trachomatis is a bacterium; herpes (HSV) and genital warts (HPV) are viral infections.

Question 34

Who discovered Plasmodium in the red blood cells of human beings?

Accepted Answer

Answer reason: Alphonse Laveran first observed the malaria parasite (Plasmodium) inside human red blood cells in 1880; Ross later demonstrated mosquito transmission.

Question 35

The Dick test is used to diagnose which disease?

Accepted Answer

Answer reason: The Dick test checks susceptibility to the erythrogenic toxin of Streptococcus pyogenes, identifying scarlet fever risk; it is not used for yellow fever or RMSF.

Question 36

What is the most important cause of diarrhea in infants and children?

Accepted Answer

Answer reason: Rotavirus is the leading cause of acute gastroenteritis and severe diarrhea in infants and young children worldwide, surpassing bacterial causes such as E. coli, Salmonella, or Vibrio cholera.

Question 37

Boiling water helps in killing all organisms except which one?

Accepted Answer

Answer reason: Boiling kills vegetative forms of microbes (bacteria, fungi, protozoa) but not heat-resistant bacterial spores; sterilization methods like autoclaving are needed for spores.

Question 38

A client with a diagnosis of HPV is at risk for which of the following?

Accepted Answer

Answer reason: High-risk human papillomavirus (especially types 16 and 18) is causally linked to cervical intraepithelial neoplasia and cervical cancer, not to Hodgkin's lymphoma, multiple myeloma, or ovarian cancer.

Question 39

A client visiting a family planning clinic is suspected of having an STI. The best diagnostic test for treponema pallidum is?

Accepted Answer

Answer reason: FTA is a specific treponemal test that confirms Treponema pallidum infection. VDRL and RPR are nonspecific screening tests, and Thayer-Martin culture is for Neisseria gonorrhoeae.

Question 40

What can cause meningitis?

Accepted Answer

Answer reason: Bacteria are a well-established cause of meningitis and represent the classic, clinically significant etiology.

Question 41

What enters the human body to transmit Plasmodium?

Accepted Answer

Answer reason: The infective stage injected into humans by the female Anopheles mosquito is the sporozoite; trophozoite and haemozoin are blood-stage forms/pigment and not the transmitted form.

Question 42

Typhoid fever is caused by which type of organism?

Accepted Answer

Answer reason: Typhoid fever is caused by Salmonella enterica serovar Typhi, a bacterium.

Question 43

Break bone fever is which disease?

Accepted Answer

Answer reason: Breakbone fever is the common nickname for dengue infection due to severe myalgias and arthralgia.

Question 44

What substance is found in the cell wall of fungi?

Accepted Answer

Answer reason: Fungal cell walls are composed mainly of chitin and glucans; cellulose, pectin, and lignin are plant cell wall components.

Question 45

How is an inoculating loop sterilized?

Accepted Answer

Answer reason: Inoculating loops are sterilized by passing them through a flame until red-hot. Ovens and autoclaves are for instruments; radiation is not used for quick loop sterilization.

Question 46

Which virus is responsible for causing AIDS?

Accepted Answer

Answer reason: AIDS is caused by infection with human immunodeficiency virus (HIV); the other listed viruses cause different diseases (influenza, HPV-related conditions, and hepatitis B).

Question 47

What causes malaria?

Accepted Answer

Answer reason: Malaria is caused by Plasmodium protozoan parasites transmitted by Anopheles mosquitoes.

Question 48

What is the most common cause of meningoencephalitis in children?

Accepted Answer

Answer reason: Enteroviruses (e.g., coxsackie and echoviruses) are the most common cause of aseptic meningitis and meningoencephalitis in children; HSV is a common cause of sporadic encephalitis but not the most common in children.

Question 49

Which of the following communicable diseases is also termed 'Rubeola'?

Accepted Answer

Answer reason: Rubeola is the medical term for measles; rubella refers to German measles.

Question 50

Which illness caused by a virus usually affects the parotid glands on each side of the face?

Accepted Answer

Answer reason: Mumps virus classically causes painful swelling of the parotid glands (parotitis), often bilaterally.

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