MICROBIOLOGY LATEST UPDATED 2025-2026 MIDTERM EXAM
WITH COMPLETE DETAILED QUESTIONS AND CORRECT
VERIFIED ANSWERS ALREADY A+ GRADED
What is the concept of spontaneous generation?
ANSWER-living organisms could develop from nonliving or decomposing matter
Who challenged the concept of spontaneous generation by showing that maggots on decaying
meat came from flies, not from the meat itself?
ANSWER-Francesco Redi
Who showed that mutton broth boiled in flasks and then sealed could still develop
microorganisms, which supported the theory of spontaneous generation?
ANSWER-John Needham
Who showed that flasks sealed and then boiled had no growth of microorganisms?
ANSWER-Lazzaro Spallanzani
Who proposed that air carried germs?
ANSWER-Spallanzani
Who disproved the theory of spontaneous generation?
ANSWER-Louis Pasteur
Who demonstrated that dust carried microbes and proved evidence for the existence of heat-
resistant forms of bacteria?
ANSWER-John Tyndall
Who showed that a silkworm disease was caused by a fungus?
ANSWER-Agostino Bassi
Who demonstrated that the Great Potato Blight was caused by a water mold?
ANSWER-M. J. Berkely
Who showed that the pebrine disease of silkworms was caused by a protozoan parasite?
,ANSWER-Louis Pasteur
Who developed a system of surgery designed to prevent microorganisms from entering
wounds?
ANSWER-John Lister
Who transformed the practice of surgery?
ANSWER-John Lister
Who established the relationship between Bacillus anthracis and anthrax?
ANSWER-Robert Koch
What are the Koch Postulates?
ANSWER-1.The microorganisms must be present in every case of the disease but absent from
healthy individuals
2.The suspected microorganisms must be isolated and grown in pure culture
3. The same disease must result when the isolated microorganism is inoculated into a healthy
host
4. The same microorganism must be isolated again from the diseased host
Limitations of Koch's Postulates
-Some organisms cannot be grown in pure culture
-Using humans in completing the postulates is unethical
-Molecular and genetic evidence may replace
What vaccination did Edward Jenner make?
ANSWER-smallpox vaccination
What vaccinations did Pasteur produce?
chicken cholera, rabies and anthrax
Who induced formation of dipped toxin-antitoxins rabbits
Emil von Behring and Shibasaburo Kitasato
Who showed that the silkworm disease was caused by fungus?
ANSWER-Bassi
Who demonstrated that the Great Potato Blight of Ireland was caused by a water mold?
,ANSWER-M.J. Berkeley
Who showed that the perbrine disease of silkworms was caused by a protozoan parasite?
ANSWER-Louis Pasteur
A simple morphology and lack a true membrane-delimited nucleus
ANSWER-prokaryotes
What is a morphologically complex and has a membrane-enclosed nucleus?
ANSWER-Eucaryotes
What let to the discovery of viruses as disease causing agents?
ANSWER-bacterial filter that removed bacteria and larger microbes (Charles Chamberland)
The five kingdom classification scheme is
ANSWER-the Monera or Procaryotae, Protista, Fungi, Animalia, and Plantae
What are ribozymes?
RNA molecules that form peptide bonds and perform cellular work and replication
The three domain scheme is
Bacteria, Archaea, and Eucarya
The three domain scheme is based on?
a comparaison of ribosomal RNA
The earliest cells may have been
RNA surrounded by liposomes
What are the three bacterial morphology?
-bacillus (little rod)
-coccus (grain or berry)
-spirillum (coiled or helical)
What are the types of light microscopes?
-bright-field microscope
-dark-field microscope
, -phase-contrast microscope
-fluorescence microscopes
What is a measure of how greatly a substance slows the velocity of light?
Refractive index
The direction and magnitude of bending light in a microscope is determined by the _____
refractive indexes of the two media forming the interface
Which microscope produces a dark image against a brighter background?
the bright-field microscope
What is the product of the magnifications of the ocular lens and the objective lens?
the total magnification
What is the total magnification of the bright field, dark field, and phase-contrast microscopes?
2000x
What is the total resolution of the bright field, dark field, and phase contrast microscopes?
0.2um
What is the purpose of the bright field microscope?
for live and preserved stained specimens
What is the purpose of the dark field microscope?
to observe living, unstained preparations
Which microscopes are good for observing living cells?
-The Differential Interference Contrast Microscope
-Phase-contrast microscope
Which microscope enhances the contrast between intracellular structures having slight
differences in the refractive index?
phase-contrast microscope
Which microscope shows a bright image of the object resulting from the fluorescent light
emitted by the specimen?
the fluorescence microscope
WITH COMPLETE DETAILED QUESTIONS AND CORRECT
VERIFIED ANSWERS ALREADY A+ GRADED
What is the concept of spontaneous generation?
ANSWER-living organisms could develop from nonliving or decomposing matter
Who challenged the concept of spontaneous generation by showing that maggots on decaying
meat came from flies, not from the meat itself?
ANSWER-Francesco Redi
Who showed that mutton broth boiled in flasks and then sealed could still develop
microorganisms, which supported the theory of spontaneous generation?
ANSWER-John Needham
Who showed that flasks sealed and then boiled had no growth of microorganisms?
ANSWER-Lazzaro Spallanzani
Who proposed that air carried germs?
ANSWER-Spallanzani
Who disproved the theory of spontaneous generation?
ANSWER-Louis Pasteur
Who demonstrated that dust carried microbes and proved evidence for the existence of heat-
resistant forms of bacteria?
ANSWER-John Tyndall
Who showed that a silkworm disease was caused by a fungus?
ANSWER-Agostino Bassi
Who demonstrated that the Great Potato Blight was caused by a water mold?
ANSWER-M. J. Berkely
Who showed that the pebrine disease of silkworms was caused by a protozoan parasite?
,ANSWER-Louis Pasteur
Who developed a system of surgery designed to prevent microorganisms from entering
wounds?
ANSWER-John Lister
Who transformed the practice of surgery?
ANSWER-John Lister
Who established the relationship between Bacillus anthracis and anthrax?
ANSWER-Robert Koch
What are the Koch Postulates?
ANSWER-1.The microorganisms must be present in every case of the disease but absent from
healthy individuals
2.The suspected microorganisms must be isolated and grown in pure culture
3. The same disease must result when the isolated microorganism is inoculated into a healthy
host
4. The same microorganism must be isolated again from the diseased host
Limitations of Koch's Postulates
-Some organisms cannot be grown in pure culture
-Using humans in completing the postulates is unethical
-Molecular and genetic evidence may replace
What vaccination did Edward Jenner make?
ANSWER-smallpox vaccination
What vaccinations did Pasteur produce?
chicken cholera, rabies and anthrax
Who induced formation of dipped toxin-antitoxins rabbits
Emil von Behring and Shibasaburo Kitasato
Who showed that the silkworm disease was caused by fungus?
ANSWER-Bassi
Who demonstrated that the Great Potato Blight of Ireland was caused by a water mold?
,ANSWER-M.J. Berkeley
Who showed that the perbrine disease of silkworms was caused by a protozoan parasite?
ANSWER-Louis Pasteur
A simple morphology and lack a true membrane-delimited nucleus
ANSWER-prokaryotes
What is a morphologically complex and has a membrane-enclosed nucleus?
ANSWER-Eucaryotes
What let to the discovery of viruses as disease causing agents?
ANSWER-bacterial filter that removed bacteria and larger microbes (Charles Chamberland)
The five kingdom classification scheme is
ANSWER-the Monera or Procaryotae, Protista, Fungi, Animalia, and Plantae
What are ribozymes?
RNA molecules that form peptide bonds and perform cellular work and replication
The three domain scheme is
Bacteria, Archaea, and Eucarya
The three domain scheme is based on?
a comparaison of ribosomal RNA
The earliest cells may have been
RNA surrounded by liposomes
What are the three bacterial morphology?
-bacillus (little rod)
-coccus (grain or berry)
-spirillum (coiled or helical)
What are the types of light microscopes?
-bright-field microscope
-dark-field microscope
, -phase-contrast microscope
-fluorescence microscopes
What is a measure of how greatly a substance slows the velocity of light?
Refractive index
The direction and magnitude of bending light in a microscope is determined by the _____
refractive indexes of the two media forming the interface
Which microscope produces a dark image against a brighter background?
the bright-field microscope
What is the product of the magnifications of the ocular lens and the objective lens?
the total magnification
What is the total magnification of the bright field, dark field, and phase-contrast microscopes?
2000x
What is the total resolution of the bright field, dark field, and phase contrast microscopes?
0.2um
What is the purpose of the bright field microscope?
for live and preserved stained specimens
What is the purpose of the dark field microscope?
to observe living, unstained preparations
Which microscopes are good for observing living cells?
-The Differential Interference Contrast Microscope
-Phase-contrast microscope
Which microscope enhances the contrast between intracellular structures having slight
differences in the refractive index?
phase-contrast microscope
Which microscope shows a bright image of the object resulting from the fluorescent light
emitted by the specimen?
the fluorescence microscope
