LSU BIOL 2051 Exam #1 –
Bhattacharyya Final Test Questions
with Guaranteed Pass Solutions 2026.
what are Koch's 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 in a healthy host
4. the same microorganism must be isolated again from the diseased host
why was the discovery of phagocytic cells in the blood important? - Answer foundational
discovery for CELL-MEDIATED IMMUNITY
why does the field of microbiology include macroscopic organisms like algae and fungi? -
Answer their study requires techniques like isolation, sterilization, and culturing
what is scanning electron microscope (SEM) used for? - Answer observing a specimen's
three dimensional topography
what limitation does heat fixing a bacterial smear have? - Answer distorts internal stuctures
what is the primary stain used in gram staining procedures? - Answer crystal violet
what is the purpose of applying a counterstain in a differential staining procedure? - Answer
adds a visible color to the decolorized cells
what is the purpose of using mordant in flagella staining? - Answer increases the diameter of
the flagella to make them visible
what is the term for bending light as it passes from one medium to another? - Answer
refraction
what was the feature of Pasteur's swan neck flasks that prevented contamination of the sterile
broth? - Answer long curved neck trapped airborne microbes and dust
what microscope has a resolution powerful enough to observe individual atoms? - Answer
scanning tunneling electron microscope
,which microscope is suited for observing intracellular structures by enhancing contrast in living
cells that have slight differences in refractive index? - Answer phase-contrast microscope
which staining technique is used to visualize bacterial capsules? - Answer negative staining
which type of microscope produces a bright image of an object against a dark background and is
ideal for observing living unstained specimens? - Answer dark field microscope
which type of microscope uses a beam of electrons passing through a thin section of specimen
to create an image of its internal structures? - Answer transmission electron microscope
(TEM)
who demonstrated that dust is a carrier of microbes and also provided evidence for heat
resistant bacteria? - Answer john tyndall
who developed antiseptic surgical techniques to prevent wound infection and indirect evidence
for germ theory of disease? - Answer joseph lister
who was the first person to observe and describe microorganisms using his own microscope? -
Answer antony van leeuwenhoek
what type of light does a fluorescence microscope require the specimen be exposed to excite its
fluorophores? - Answer ultraviolet, violet, or blue light
what genus of bacteria is identified using acid fast staining as a differential procedure? - Answer
mycobacterium
what vaccination did Edward Jenner pioneer that uses material from cowpox lesions? - Answer
smallpox
what is the function of iodine in gram staining? - Answer serves as a mordant, forming an
insoluble complex with the primary stain
what vaccines did Pasteur develop? - Answer anthrax, rabies, and chicken cholera
what is microscope resolution? - Answer the ability of the microscope lens to distinguish
between two small objects that are close together
,what is the atomic force microscope used for? - Answer viewing surfaces that do not
conduct electricity well
what is the outcome of the gram stain procedure? - Answer the alcohol decolorizer dissolves
the gram negative outer membrane and washes the dye complex out through the thin
peptidoglycan later
what is a similarity between prokaryotic nucleoid and the eukaryotic nucleus? - Answer the
use of DNA as the repository of genetic info
which component is primarily responsible for the pyrogenic activity associated with gram
negative sepsis and constitutes a major part of the outer membrane? - Answer
lipopolysaccharide (LPS)
what could happen if a virus mutates and prevents the synthesis of its own polysaccharide
capsule? - Answer the bacteria will be highly susceptible to phagocytosis by host immune
cells
which surface appendage is essential for bacterial conjugated and has the ability to bind to
certain bacteriophages? - Answer sex pilus
what do bacterial plasma membranes usually lack? - Answer sterols like cholesterols
what two things make bacterial endospores highly heat resistant? - Answer dehydrated state
and high concentration of calcium dipicolinate
what is unique about the capsule of Bacillus anthracis? - Answer it is composed of a y-
glutamyl polypeptide
why is the periplasmic space of gram negative bacteria a functionally distinct compartment? -
Answer it contains hydrolytic enzymes, binding proteins, and chemoreceptors
what energizes the rotational motor of a bacterial flagellum? - Answer transmembrane flow
of protons (proton motive force)
at what stage of sporulation does the asymmetric cell division that segregates the chromosome
and creates a forespore occur? - Answer stage 2
what primary structural difference in the peptidoglycan of E. coli and Staphylococcus aureus? -
Answer the E coli peptidoglycan is thinner and less extensively cross linked
, what will happen if a gram positive bacteria is treated with lysozome while suspended in a
hypotonic solution? - Answer the cell will undergo osmotic lysis
where does the respiratory chain, ATP synthesis, and biosynthesis of membrane lipids and cell
wall polymers take place in bacterial cells? - Answer plasma membrane
which organism would be susceptible to an antibiotic that inhibits transpeptidase enzymes and
is responsible for foriming peptide bridges in peptidoglycan? - Answer Stapholococcus
aureus
what makes lipoteichoic acids (LTAs) structurally and functionally different from wall teichoic
acids (WTAs)? - Answer they are anchored in the cytoplasmic membrane by a lipid moeity
what organism domain does a prokaryote with a cell wall that contains talosaminuronic acid
and lack D-amino acids? - Answer archaea domain
what is the role of porin proteins found in the outer membrane of E. coli? - Answer to form
non-specific channels for the diffusion of small hydrophilic molcules
if the adhesion of certain strains of E. coli to host cells can be blocked by monosaccharide
mannose which is mediated by lectin like proteins, then structure is this mediated on? - Answer
common pili (fimbriae)
what is a medium called when all chemical components are precisely known and quantified? -
Answer synthetic medium
what type of media would be used to determine if a microbe has the ability to ferment a
specific sugar? - Answer carbohydrate fermentation media
what is a culture that consists of a single microbial species without any contaminants? - Answer
pure culture
a reducing medium that limits free oxgen is specifically designed for cultivating what type of
microorganisms? - Answer anaerobes
which isolation method involves embedding a diluted sample within liquefied agar that is then
solidified in a plate? - Answer pour plate
Bhattacharyya Final Test Questions
with Guaranteed Pass Solutions 2026.
what are Koch's 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 in a healthy host
4. the same microorganism must be isolated again from the diseased host
why was the discovery of phagocytic cells in the blood important? - Answer foundational
discovery for CELL-MEDIATED IMMUNITY
why does the field of microbiology include macroscopic organisms like algae and fungi? -
Answer their study requires techniques like isolation, sterilization, and culturing
what is scanning electron microscope (SEM) used for? - Answer observing a specimen's
three dimensional topography
what limitation does heat fixing a bacterial smear have? - Answer distorts internal stuctures
what is the primary stain used in gram staining procedures? - Answer crystal violet
what is the purpose of applying a counterstain in a differential staining procedure? - Answer
adds a visible color to the decolorized cells
what is the purpose of using mordant in flagella staining? - Answer increases the diameter of
the flagella to make them visible
what is the term for bending light as it passes from one medium to another? - Answer
refraction
what was the feature of Pasteur's swan neck flasks that prevented contamination of the sterile
broth? - Answer long curved neck trapped airborne microbes and dust
what microscope has a resolution powerful enough to observe individual atoms? - Answer
scanning tunneling electron microscope
,which microscope is suited for observing intracellular structures by enhancing contrast in living
cells that have slight differences in refractive index? - Answer phase-contrast microscope
which staining technique is used to visualize bacterial capsules? - Answer negative staining
which type of microscope produces a bright image of an object against a dark background and is
ideal for observing living unstained specimens? - Answer dark field microscope
which type of microscope uses a beam of electrons passing through a thin section of specimen
to create an image of its internal structures? - Answer transmission electron microscope
(TEM)
who demonstrated that dust is a carrier of microbes and also provided evidence for heat
resistant bacteria? - Answer john tyndall
who developed antiseptic surgical techniques to prevent wound infection and indirect evidence
for germ theory of disease? - Answer joseph lister
who was the first person to observe and describe microorganisms using his own microscope? -
Answer antony van leeuwenhoek
what type of light does a fluorescence microscope require the specimen be exposed to excite its
fluorophores? - Answer ultraviolet, violet, or blue light
what genus of bacteria is identified using acid fast staining as a differential procedure? - Answer
mycobacterium
what vaccination did Edward Jenner pioneer that uses material from cowpox lesions? - Answer
smallpox
what is the function of iodine in gram staining? - Answer serves as a mordant, forming an
insoluble complex with the primary stain
what vaccines did Pasteur develop? - Answer anthrax, rabies, and chicken cholera
what is microscope resolution? - Answer the ability of the microscope lens to distinguish
between two small objects that are close together
,what is the atomic force microscope used for? - Answer viewing surfaces that do not
conduct electricity well
what is the outcome of the gram stain procedure? - Answer the alcohol decolorizer dissolves
the gram negative outer membrane and washes the dye complex out through the thin
peptidoglycan later
what is a similarity between prokaryotic nucleoid and the eukaryotic nucleus? - Answer the
use of DNA as the repository of genetic info
which component is primarily responsible for the pyrogenic activity associated with gram
negative sepsis and constitutes a major part of the outer membrane? - Answer
lipopolysaccharide (LPS)
what could happen if a virus mutates and prevents the synthesis of its own polysaccharide
capsule? - Answer the bacteria will be highly susceptible to phagocytosis by host immune
cells
which surface appendage is essential for bacterial conjugated and has the ability to bind to
certain bacteriophages? - Answer sex pilus
what do bacterial plasma membranes usually lack? - Answer sterols like cholesterols
what two things make bacterial endospores highly heat resistant? - Answer dehydrated state
and high concentration of calcium dipicolinate
what is unique about the capsule of Bacillus anthracis? - Answer it is composed of a y-
glutamyl polypeptide
why is the periplasmic space of gram negative bacteria a functionally distinct compartment? -
Answer it contains hydrolytic enzymes, binding proteins, and chemoreceptors
what energizes the rotational motor of a bacterial flagellum? - Answer transmembrane flow
of protons (proton motive force)
at what stage of sporulation does the asymmetric cell division that segregates the chromosome
and creates a forespore occur? - Answer stage 2
what primary structural difference in the peptidoglycan of E. coli and Staphylococcus aureus? -
Answer the E coli peptidoglycan is thinner and less extensively cross linked
, what will happen if a gram positive bacteria is treated with lysozome while suspended in a
hypotonic solution? - Answer the cell will undergo osmotic lysis
where does the respiratory chain, ATP synthesis, and biosynthesis of membrane lipids and cell
wall polymers take place in bacterial cells? - Answer plasma membrane
which organism would be susceptible to an antibiotic that inhibits transpeptidase enzymes and
is responsible for foriming peptide bridges in peptidoglycan? - Answer Stapholococcus
aureus
what makes lipoteichoic acids (LTAs) structurally and functionally different from wall teichoic
acids (WTAs)? - Answer they are anchored in the cytoplasmic membrane by a lipid moeity
what organism domain does a prokaryote with a cell wall that contains talosaminuronic acid
and lack D-amino acids? - Answer archaea domain
what is the role of porin proteins found in the outer membrane of E. coli? - Answer to form
non-specific channels for the diffusion of small hydrophilic molcules
if the adhesion of certain strains of E. coli to host cells can be blocked by monosaccharide
mannose which is mediated by lectin like proteins, then structure is this mediated on? - Answer
common pili (fimbriae)
what is a medium called when all chemical components are precisely known and quantified? -
Answer synthetic medium
what type of media would be used to determine if a microbe has the ability to ferment a
specific sugar? - Answer carbohydrate fermentation media
what is a culture that consists of a single microbial species without any contaminants? - Answer
pure culture
a reducing medium that limits free oxgen is specifically designed for cultivating what type of
microorganisms? - Answer anaerobes
which isolation method involves embedding a diluted sample within liquefied agar that is then
solidified in a plate? - Answer pour plate
