Q.1 Who is considered the father of microbiology?
Louis Pasteur
Robert Koch
Anton van Leeuwenhoek
Joseph Lister
Explanation - Anton van Leeuwenhoek was the first to observe and describe microorganisms using his simple microscopes, earning him the title of father of microbiology.
Correct answer is: Anton van Leeuwenhoek
Q.2 Which scientist developed pure culture techniques?
Louis Pasteur
Robert Koch
Joseph Lister
Edward Jenner
Explanation - Robert Koch introduced pure culture methods, which allowed the isolation of microorganisms in a laboratory setting.
Correct answer is: Robert Koch
Q.3 Which of the following is NOT a prokaryote?
Bacteria
Archaea
Fungi
Cyanobacteria
Explanation - Fungi are eukaryotic organisms with membrane-bound nuclei, unlike bacteria and archaea which are prokaryotic.
Correct answer is: Fungi
Q.4 What is the main structural difference between Gram-positive and Gram-negative bacteria?
Shape
Presence of capsule
Cell wall composition
Ribosome type
Explanation - Gram-positive bacteria have thick peptidoglycan layers, whereas Gram-negative bacteria have thin peptidoglycan layers and an outer membrane.
Correct answer is: Cell wall composition
Q.5 Which scientist is known for disproving spontaneous generation?
Francesco Redi
Louis Pasteur
John Needham
Robert Hooke
Explanation - Louis Pasteur demonstrated through swan-neck flask experiments that microorganisms arise from existing microbes, not spontaneous generation.
Correct answer is: Louis Pasteur
Q.6 Which type of microscope is commonly used in microbiology labs for routine observation?
Electron microscope
Compound light microscope
Phase contrast microscope
Confocal microscope
Explanation - Compound light microscopes are widely used for routine observation of microbial morphology.
Correct answer is: Compound light microscope
Q.7 What is the typical size range of bacteria?
0.2–2 µm
10–100 µm
100–500 µm
1–2 mm
Explanation - Most bacteria fall within the size range of 0.2 to 2 micrometers.
Correct answer is: 0.2–2 µm
Q.8 Which structure is responsible for bacterial motility?
Pili
Fimbriae
Flagella
Capsule
Explanation - Flagella are whip-like structures that allow bacteria to move.
Correct answer is: Flagella
Q.9 What does the term 'pathogen' mean?
Any microorganism
A harmless microbe
A disease-causing organism
A beneficial organism
Explanation - Pathogens are microorganisms that cause disease in their host.
Correct answer is: A disease-causing organism
Q.10 Which domain of life do bacteria belong to?
Eukarya
Bacteria
Archaea
Protista
Explanation - Bacteria are prokaryotic organisms classified under the domain Bacteria.
Correct answer is: Bacteria
Q.11 What is the role of Koch’s postulates?
To classify bacteria
To prove a microbe causes a disease
To identify antibiotics
To study immunity
Explanation - Koch’s postulates provide a framework for establishing that a microorganism causes a particular disease.
Correct answer is: To prove a microbe causes a disease
Q.12 Which stain is used in Gram staining as the primary stain?
Safranin
Crystal violet
Methylene blue
Carbol fuchsin
Explanation - Crystal violet is the primary stain that initially colors both Gram-positive and Gram-negative bacteria.
Correct answer is: Crystal violet
Q.13 Who discovered penicillin?
Alexander Fleming
Joseph Lister
Paul Ehrlich
Louis Pasteur
Explanation - Alexander Fleming discovered penicillin in 1928, revolutionizing antimicrobial therapy.
Correct answer is: Alexander Fleming
Q.14 Which component of bacteria is targeted by penicillin?
Ribosome
Cell membrane
Peptidoglycan cell wall
DNA
Explanation - Penicillin interferes with bacterial cell wall synthesis by inhibiting peptidoglycan cross-linking.
Correct answer is: Peptidoglycan cell wall
Q.15 Which of the following is NOT a bacterial shape?
Coccus
Bacillus
Spirillum
Chloroplast
Explanation - Coccus, bacillus, and spirillum are bacterial shapes, while chloroplast is a eukaryotic organelle.
Correct answer is: Chloroplast
Q.16 Which part of bacteria helps in attachment to surfaces?
Flagella
Fimbriae
Capsule
Endospore
Explanation - Fimbriae are hair-like structures that help bacteria adhere to surfaces and host tissues.
Correct answer is: Fimbriae
Q.17 What is microbiome?
A lab culture of bacteria
The collection of microbes in an environment
The genetic material of a single bacterium
A type of microscope
Explanation - Microbiome refers to the community of microorganisms living in a particular environment, such as the human gut.
Correct answer is: The collection of microbes in an environment
Q.18 Which scientist introduced antiseptic techniques in surgery?
Joseph Lister
Robert Koch
Louis Pasteur
Edward Jenner
Explanation - Joseph Lister used carbolic acid as an antiseptic, greatly reducing surgical infections.
Correct answer is: Joseph Lister
Q.19 Which term refers to bacteria that thrive at high salt concentrations?
Halophiles
Thermophiles
Acidophiles
Psychrophiles
Explanation - Halophiles are salt-loving microorganisms that thrive in high salt environments.
Correct answer is: Halophiles
Q.20 Which staining method is used to detect Mycobacterium tuberculosis?
Gram stain
Acid-fast stain
Endospore stain
Negative stain
Explanation - Acid-fast staining is used for Mycobacterium due to its waxy mycolic acid-rich cell wall.
Correct answer is: Acid-fast stain
Q.21 Viruses are classified as:
Prokaryotes
Eukaryotes
Non-cellular entities
Fungi
Explanation - Viruses are acellular, consisting of nucleic acid and protein coats, and require host cells for replication.
Correct answer is: Non-cellular entities
Q.22 Which organelle do prokaryotes lack?
Ribosomes
Nucleus
Plasma membrane
Cytoplasm
Explanation - Prokaryotes lack a membrane-bound nucleus, but they do contain ribosomes, plasma membrane, and cytoplasm.
Correct answer is: Nucleus
Q.23 Which scientist developed the first vaccine for smallpox?
Edward Jenner
Louis Pasteur
Alexander Fleming
Robert Koch
Explanation - Edward Jenner pioneered vaccination by using cowpox to provide immunity against smallpox.
Correct answer is: Edward Jenner
Q.24 Endospores are formed by bacteria mainly for:
Reproduction
Nutrient storage
Survival in harsh conditions
Motility
Explanation - Endospores are resistant structures formed by some bacteria to withstand extreme environmental stress.
Correct answer is: Survival in harsh conditions
Q.25 What is the main difference between eukaryotic and prokaryotic ribosomes?
Protein content
Size
Presence in cytoplasm
Ability to make DNA
Explanation - Prokaryotic ribosomes are 70S, while eukaryotic ribosomes are 80S in size.
Correct answer is: Size