micro cumulative final review
All cellular organisms are classified as
A. Bacteria
B. Archaea
C. Eukarya
All three are cellular organism classifications.
Protists contain all of the following forms of life except
A.protozoa
B.fungi
C.slime molds
D.algae
E. amoeba
fungi
True or False: Viruses are not generally studied by microbiologists because they are not classified as living organisms
False
True or False: Prokaryotes have a relatively complex morphology and a true,membrane-delimited nucleus.
False
Which of the following distinguish the field of microbiology from other fields of biology?
A.The size of the organism studied.
B.The techniques used to study organisms regardless of their size.
C.Both the size of the organism studied and the techniques employed in the study of organisms.
D.Neither the size of the organism studied nor the techniques employed in the study of organisms regardless of their size.
Both the size of the organism studied and the techniques employed in the study of organisms.
The concept that living organisms arise from nonliving material is called
Spontaneous generation
__was the first to observe and accurately describe microorganisms.
van Leeuwenhoek
Redi’s experiment included both a dish of meat covered with cheesecloth and an uncovered dish of meat to show
A. maggots did not appear under any circumstances
B. spontaneous generation would occur if the air could get to the meat
C. that maggots would only appear if flies had access to the meat
D. that bacteria would not grow on the meat
E. air was necessary to produce maggots
that maggots would only appear if flies had access to the meat
The first step in using Koch’s method for determining the organism causing disease is to:
A. Observe the organism in sick animals, but not healthy ones
B. Isolate the different organisms in sick animals, and inject them into healthy subjects
C. Identify the species of the organisms infecting sick animals
D. Grow each organism in pure culture
E. Observe the same disease in animals injected with the purified organism
Observe the organism in sick animals, but not healthy ones
True or False: Although developed over 100 years ago, Koch's postulates continue to be used successfully in all known human infectious diseases.
False
True or False: All microorganisms can be grown on nutrient agar plates
False
If you are working in a laboratory and wish to create a pure culture of a virus, which of the following would best allow you to do this?
A. A nutrient agar plate with LB media.
B. A tube of nutrient media broth.
C. A flask of living cells and nutrient media.
D. All of the above would allow you to do this.
E. None of the above as viruses cannot be cultured in the lab.
A flask of living cells and nutrient media.
The branch of microbiology that deals with the mechanisms by which the human body protects itself from disease-causing organisms is called _____
Immunology
__ microbiology involves the use of microorganisms to make products such as antibiotics, vaccines, steroids, alcohols, vitamins, amino acids, and enzymes.
Industrial microbiology
True or False: . When looking through a compound microscope at an image, the visual image seen is actually upside down
True
18. What is the purpose of a lens in a microscope?
A. To focus light rays at a specific place called the focal point.
B. To bend and refract light waves away from a specimen on a slide.
C. To provide a light source under a specimen.
D. To improve resolution of the image through adjustments of the stage.
E. To measure the ability to gather light and resolve fine specimen detail at a fixed object distance
A. To focus light rays at a specific place called the focal point.
The _____________ is a measure of how greatly a substance slows the velocity of light.
A. reflective index
B. condensing power
C. refractive index
D. resolving powe
rE. condenser
refractive index
Which of the following would provide the greatest amount of resolution in a microscope?
A. A low power magnification
B. A larger numerical aperture
C. A shorter focal length
D. B and C together would give the best resolution
E. All of the abovetogetherwould give the best resolution possible
Both a larger numerical aperture and a shorter focal length
In______________ the visual image is formed by light reflected or refracted by the specimen and is used to view a bright image of the object against a dark background
dark-field microscopy
In ______________ the visual image is formed by converting differences in refractive index/cell density into detected variations in light intensity.
Phase-contrast microscopy
_____________ produces a magnification of 100 million times and can view atoms on a solid surface.
Scanning probe microscopy
True or False: An advantage of phase contrast microscopy is that living cells do not have to be killed with stains in order to be visualized.
True
Which of the following is NOT true about SEM (scanning electron microscopy)
A. Uses electrons excited from the surface of a specimen to create detailed image
B. Can create 3-D images
C. Creates images using the back scatter of electrons or by capturing secondary electrons from the surface of the object to be visualized.
D. Images produced by SEM gain colors based on the fluorescent indexes of electrons
E. All of the above are true about SEM.
Images produced by SEM gain colors based on the fluorescent indexes of electrons
True or False: "Microbiologists study a variety of organisms, but all are considered either Bacteria or Archaea"
False
A mis-folded protein
A prion
Cells with a relatively complex morphology that have a true membrane-delimited nucleus are called
eukaryotes
The concept that human and animal diseases are caused by microorganisms is called the
Germ Theory
Who of the following developed a set of criteria that could be used to establish a causative link between a particular microorganism and a particular disease?
Fracastoro
Koch
Pasteur
Lister
Koch
Who of the following was the first to observe and accurately describe microorganisms?
van Leeuwenhoek
Koch
Semmelweiss
Lister
van Leeuwenhoek
Who of the following provided the evidence needed to discredit the concept of spontaneous generation?
Pasteur Koch Semmelweiss Lister
Pasteur
True or False: The relationship between specific bacteria and specific diseases was first demonstrated by Koch.
True
Whose work on spontaneous generation first demonstrated the existence of a very heat-resistant form of bacteria that are called endospores?
Schwann Redi Tyndall Pasteur
Tyndall
Antiseptic surgery was pioneered by
Pasteur Jenner Lister Kitasato
Lister
True or False: "Although developed over 100 years ago, Koch's postulates continue to be used successfully in all known human infectious diseases. "
False
True or False: Agar is used as a solidifying agent for microbiological media because it is not readily digested by most microorganisms.
True
True or False: All microorganisms can be grown on nutrient agar plates.
False
"If you are working in a laboratory and wish to create a pure culture of a virus, which of the following would best allow you to do this?"
A nutrient agar plate with LB media.
A tube of nutrient media broth.
A flask of living cells and nutrient media.
All of the above would allow you to do this.
A flask of living cells and nutrient media.
The branch of microbiology that deals with diseases of humans and animals is called __________ microbiology.
Medical microbiology
The branch of microbiology that deals with the mechanisms by which the human body protects itself from disease-causing organisms is called __________.
Immunology
__________ microbiologists monitor community food establishments and water supplies in order to control the spread of communicable diseases.
Public Health
The branch of microbiology that studies the relationship between microorganisms and their habitats is called __________.
Microbial ecology
"__________ microbiology involves the use of microorganisms to make products such as antibiotics, vaccines, steroids, alcohols, vitamins, amino acids, and enzymes. "
Industrial
"In an outbreak of the bacteria E. coli, who would be the most likely type of microbiologist to respond to the outbreak?"
An immunologist
An industrial microbiologist
A public health microbiologist
A molecular geneticis
A public health microbiologist
. Which of the following external structures are found in archaea but not bacteria?
A. pili
B. flagella
C. hami
D. peptidoglycan
E. All of the above are found in both bacteria and archaea
hami
Which of the following statements about archaeal plasma membranes is TRUE?
A. The plasma membrane is always a lipid bilayer that lacks integral membrane proteins.
B. The plasma membrane must be a lipid bilayer with embedded proteins.
C. The plasma membrane contains peptidoglycan.
D. The plasma membrane can be a lipid monolayer.
E. None of the above statements are true.
The plasma membrane can be a lipid monolayer.
Diglycerol tetraether lipids __________.
A. are a characteristic feature of thermophilicbacteria
B. tend to make the membrane less rigid
C. are found in bothbacteria and archaeaD. form typical bilayer membranes in thermophilic eukaryotes
E. are found in thermophilicarchaea
are found in thermophilicarchaea
The plasma membrane of eukaryotes contains all of the following except
A. sterols
B. phosphoglycerides
C. sphingolipids
D. peptidoglycan
E. cholesterol
peptidoglycan
How do eukaryotic cells move large particles out of a cell?
A. endocytosis
B. exocytosis
C. phagocytosis
D. pinocytosis
E. group translocation
exocytosis
__________ is used for the breakdown and recycling of cytoplasmic componentsin eukaryotic cells.
A. Receptor mediated endocytosis
B. Formation of clathrin coated pits
C. Macroautophagy
D. Caveolin-dependent endocytosis
E. Macropinocytosis
Macroautophagy
Which of the following is FALSE?
A. Histones are found in chromatin.
B. Histones are used to help coil DNA.
C. Histones are proteins.
D. Groups of histones and chromatin form nucleosomes.
E. Histones are found in prokaryotic and eukaryotic microorganisms.
E. Histones are found in prokaryotic and eukaryotic microorganisms.
Bacteria have a nucleolus.
A. True
B. False
False
Which of the following provides evidence in support of the endosymbiotic hypothesis?
A. Double membrane surrounding mitochondria.
B.Double membrane surrounding chloroplasts.
C. Observation of division by binary fission in mitochondria.
D. A and B only
E. A, B, and C
Double membrane surrounding mitochondria, Double membrane surrounding chloroplasts, Observation of division by binary fission in mitochondria.
Mitochondria have their own extra nuclear DNA.
A. True
B. False
True
Which of the following statements is FALSE?
A. A virion is complete virus particle.
B. All virions have an envelope.
C. All virions have a nucleocapsid.
D. All virions have a nucleocapsid, but not all have an envelope.
E. Virion capsids are comprised of protomers.
All virions have an envelope.
Which of the following is NOT a form of viral genetic material?
A. ds DNA
B. ss DNA
C. ds RNA
D. ss RNA
E. All of the above are forms of viral genetic material.
All of the above are forms of viral genetic material.
what capsid shape is represented in the Ebola virus?
Helical
A virus that infects bacteria specifically is referred to as a
A. bacteriophage
B. bacterial virion
C. virube
D. V4
E. protease
bacteriophage
Unlike bacteria, viruses do not have enzymes.
A. True
B. False
False
Why does influenza typically infect lung cells but not brain cells?
A. Due to the preference for macrophages over neuronal cells.
B. Due to host specificity.
C. Due to tissue tropism.
D. Due to host tropism.
E. Due to tissue deselectivity.
Due to tissue tropism.
___ viruses typically lyse host cells upon release.
A. Enveloped
B. Non-enveloped
Non-enveloped
In the __________, phage DNA inserts into bacterial host genome where it is copied as a cell divides.
A. lytic cycle
B. acute cycle
C. virulent cycle
D. lysogenic cycle
E. archaeal cycle
lysogenic cycle
Genes whose expression (or abnormal expression) causes cancer are called ___________.
A. carcinogens
B. progenies
C. cancerous genes
D. prototype genes
E. oncogenes
oncogenes
A plaque in virology refers to
A. a complete virus particle
B. anincomplete virus particle
C. a complete and infectious virus particle
D. an incomplete and infectious particle
E. a complete but non-infectious particle
a complete and infectious virus particle
The smallest amount of virus needed to cause infection in 50% of exposed host cells or organisms is called the__________.
A. lethal dose
B. infectious dose
C. innocuousdose
D. preferred dose
E. virulence dose
infectious dose
____are infectious nucleic acids that encode their own capsid proteins when helped by a helper virus.
A. Satellites
B. Prions
C. Viroids
D. Virions
E. Caspases
Satellites
You diagnose a patient with Creutzfeldt-Jakob Disease. Will prescribing antibiotics help this patient with their condition?
A. Yes because it is a bacterialdisease.
B. No because it is a satellite disease.
C. No because it is a viral disease.
D. Yes because it is a viroid disease.
E. No because it is a prion disease
No because it is a prion disease
A circular shape in a microorganism is called
coccus
Diplo
Pair
Strepto
chain
Staphylo
cluster
A rod-shaped microorganism
Bacillus
A curved rod
Vibrio
A coil-shaped microogranism
Spirilla
Spiral-shaped Microorganism
Spirochete
Helical shaped microorganism
Helicobacter
These cells lack a true membrane-delimited nucleus
Prokaryotic cells
These cells have a membrane-enclosed nucleus, are more complex morphologically, and are usually larger than prokaryotic cells
Eukaryotic cells
Usually single-celled, Majority have cell wall with peptidoglycan
Most lack a membrane-bound nucleus
Ubiquitous and some live in extreme environments
Bacteria
Distinguished from Bacteria by unique rRNA gene sequences
No peptidoglycan in cell walls
Have unique membrane lipids
Some have unusual metabolic characteristics
Many live in extreme environments
Archaea
algae, protozoa, slime molds, and water molds are examples of
Protists
Yeast and mold are examples of
Fungi
smallest of all microbes
requires host cell to replicate
cause range of diseases, some cancers
Viruses
infectious agents composed of RNA
Viroids
Infectious proteins
Prions
first person to observe and describe microorganisms accurately
Antony van Leeuwenhoek (1632-1723)
Belief that life comes from nonliving matter
Spontaneous Generation
The idea that living things only come from living things
Biogenesis
discredited spontaneous generation when he showed that maggots on decaying meat came from fly eggs and did not arise from the meat its self
Francesco Redi(1626-1697)
his experiment: First boiling, then sealing mutton broth in flasks, which resulted in a cloudy broth with microogranisms
John Needham (1713-1781)
This scientist first sealed, then boiled mutton broth in flasks, which resulted in no growth of microorganisms
Lazzaro Spallanzani(1729-1799)
These two set out to show there were living things in the air
Franz Shultzeand Theodor Schwann (1836)
Swan-neck flask’ experiments answered issues of critics about air and heat
Louis Pasteur (1822-1895)
The earliest established connection between microorganisms and disease were found in human diseases such as cholera and tuberculosis.
T/F?
False
demonstrated microorganisms carried out fermentations and developed the method of pastuerization, helping French wine industry
Louis Pasteur (1822-1895)
developed a system of surgery designed to prevent microorganisms from entering wounds as well as methods for treating instruments and surgical dressings
Joseph Lister
Established the relationship between Bacillus anthracis and anthrax
Robert Koch (1843-1910)
1.The suspected disease agent must be observed in every animal that has the disease, but not in healthy animals
2. The suspected disease agent must be extracted from a diseased animal and grown in a "pure" culture away from other types of cells, i.e., isolated from other possible disease agents
3. The suspected disease agent, which has been grown in the pure culture, must now be injected into healthy animals
4. The healthy animals must become diseased and the suspected disease agent must be observed in their bodies.
Koch's Postulates
Are there any limitations to Koch’s postulates?
Some organisms cannot be grown in pure culture
Using humans in completing the postulates is unethical
Q. How can limitations to Koch's postulates be overcome?
Molecular and genetic evidence may replace and overcome these limits
revolutionized all medicine by discovering the world's first antibiotic, or bacteria killer
Alexander Fleming (1881 -1955)
___ is concerned with the impact of microorganisms on agriculture
Agricultural microbiology
____ studies metabolic pathways of microorganisms
Microbial physiology
____ study the nature of genetic information and how it regulates the development and function of cells and organisms
Molecular biology
a measure of how greatly a substance slows the velocity of light
Refractive index
Distance between center of lens and focal point
Focal Length
Light rays are focused at a specific place called
focal point
the ability to distinguish closely spaced points as separate
Resolution
Distance between the front surface of lens and surface of cover glass or specimen when it is in sharp focus
Working distance
As you increase in magnification power, what happens to the working distance?
Working distance decreases as you increase in magnification power
Shorter wavelength = ?
greater resolution
a measure of its ability to gather light and resolve fine specimen detail at a fixed object distance
Numeric aperture
Why is the highest power objective lens referred to as the “oil immersion” lens?
Oil must be used to improve the refractive index of light to allow for appropriate resolution of images under the microscope.
4 cocci in a square
tetrads
sarcinae
cubic configuration of 8 cocci
network of long, multinucleate filaments
Mycelium
Which of the following is not a macromolecule?
1. Carbohydrates
2. Proteins
3. Lipids
4. Nucleic acids
5. Carbon Dioxide
Carbon Dioxide
These macromolecules are comprised of carbon, hydrogen, and oxygen in the ratio CH2O
Carbohydrates
These are complex macromolecules made from linking together amino acids by peptide bonds
Proteins
hydrophobic molecules that include fats, steroids, and phospholipids, and play a critical role in cell membranes
Lipids
the storage facilities for all the genetic material in life
Nucleic Acids
a sugar + a phosphate + a nitrogenous base = ?
A nucelotide
required in trace amounts
Micronutrients
Mn, Zn, Co, Mo, Ni, and Cu are examples of
Micronutrients
required in relatively large amounts
Macroelements
C, H, N, O, P, S, K, Ca, Mg, and Fe are examples of
Macroelements
transport mechanism used by Bacteria and Archaea
Group Translocation
the movement of molecules from area of high concentration to low concentration
Diffusion
diffusion of small, hydrophobic molecules across the membrane
Passive transport
the transport of hydrophilic and charged molecules across the membrane
Facilitated diffusion
the movement of water across a membrane
Osmosis
When a solution is ______ the concentration of a solute is equal on both sides of the cell membrane
isotonic
When a solution is _____ the concentration of a solute is greater on the inside of the cell membrane
hypotonic
When a solution is ___________ the concentration of a solute is greater outside of the cell membrane
hypertonic
_____ requires that a cell expend energy to move molecules across a membrane.
Active Transport
a membrane-bound vesicle fuses with the membrane and expels the large molecule
Exocytosis
a vesicle forms around a large molecule and brings it into the cell
Endocytosis
Rigid structure that lies just outside the cell plasma membrane
Two types based on standard Gram staining
Peptidoglycan
stain purple; thick peptidoglycan
Gram-positive
stain pink or red; thin peptidoglycan and outer membrane
Gram-negative
Outermost layer in the cell envelope
Glycocalyx
short, thin, hairlike, proteinaceous appendages (up to 1,000/cell) that can mediate attachment to surfaces, motility, DNA uptake
Fimbriae
longer, thicker, and less numerous (1-10/cell)–and are required for conjugation
Sex pili
one flagellum
Monotrichous
flagella at each end of the cell
Polar flagellum
one flagellum at each end of cell
amphitrichous
cluster of flagella at one or both ends
Lophotrichous
flagella spread over entire surface of cell
Peritrichous
Movement toward chemical attractant or away from chemical repellent
Chemotaxis
In flagella, counterclockwise (CCW) rotation causes forward motion and is called
Run
In flagella, clockwise rotation (CW) disrupts run causing cell to stop is called
Tumble
Complex, dormant structure formed by some bacteria and is resistant to numerous environmental conditions
Endospore
Why are bacteria haploid?
They do not undergo sexual reproduction
Binary fission and budding are examples of what type of reproduction?
Asexual
True or False: There is no mitotic phase for bacteria.
True
True or False: All bacterial chromosomes are circular
False. Most bacterial chromosomes are circular
The site at which replication begins on a bacterial chromosome
origin of replication
The site at which replication is terminated, located opposite of the origin on a bacterial chromosome
Terminus
A group of proteins needed for DNA synthesis
Replisome
formation of cross walls between daughter cells
Septation
These microbes grow optimally in the presence of NaCl or other salts at a concentration above about 0.2M
Halophiles
These microbes require salt concentrations of 2M and 6.2M
Extreme Halophiles
What is the difference between a halotolerant microbe and a halophile?
“–phile” implies “a love of”. Halotolerant microbes will tolerateNaCl, but not like it
A chemical compound that releases H+to a solution is a(n)___
Acid
A compound that accepts H+and removes them from solution is a(n)__
Base
These microbes grow optimally between pH 0 and pH 5.5
Acidophiles
These microbes grow optimally between pH 5.5 and pH 7
Neutrophiles
These microbes grow optimally between pH 8.5 and pH 11.5
Alkalophiles
These microbes grow between 0 degrees C to 20 degrees C
Psychrophiles
These microbes grow between 0 degrees C to 35 degrees C
psychrotrophs
These microbes grow between 20degrees C to 45 degrees C
Mesophiles
These microbes grow between 55 degrees C to 85 degrees C
Thermophiles
These microbes grow between 85 degrees C to 113 degrees C
Hyoperthermophiles
These microbes grow in presence of atmospheric oxygen (O2) which is 20% O2
Aerobes
These microbes require O2
Obligate aerobe
These microbes grow in the absence of O2
Anaerobe
These microbes usually killed in presence of O2
Obligate anaerobe
These microbes do not require O2 but grow better in its presence
Facultative anaerobes
These microbes require 2–10% O2
Microaerophiles
____ grow with or without O2
Aerotolerant anaerobes
important antioxidant defense in nearly all living cells exposed to oxygen; out-competes damaging reactions of superoxide
Superoxide Dismutase (SOD)
Ubiquitous in nature in water, these are complex, slime enclosed communities of microbes
Biofilm
This media favors the growth of some microorganisms and inhibit growth of others
Selective media
This type of media can distinguish between different groups of microorganisms based on their biological characteristics
Differential media
True or False: Media can be selective or differential, but not both.
False. Media can be both selective and differential.
Which is not a phase in the growth curve?
Lag phase
Communal phase
Exponential(log) phase
Stationary phase
Death phase
Communal phase
At 8:00 a.m., a closed flask of sterile broth is inoculated with 1,000 cells. The lag phase lasts 2.5 hours. At 2:00 p.m. the log phase culture has a population of 6 million cells. The mean generation time is approximately_______?
3.5 hours/12.56 generations = 0.29 hours = ~20 minutes
What is used to accomplish microbial metabolism?
ATP
Chemical work, Transport work, and Mechanical work all make up
Microbial metabolism
In metabolism, the synthesis of complex molecules is __
Chemical work
In metabolism, take up of nutrients, elimination of wastes, and maintenance of ion balances is ___
Transport work
In metabolism, cell motility and movement of structures within cells is ____
Mechanical work
the breakdown of organic molecules
Catabolism
The synthesis of organic molecules
Anabolism
One is electron donating(oxidizing reaction)
One is electron accepting reaction (reducing reaction)
Oxidation-Reduction (redox) reaction
NAD, NADP, FAD, FMN, and CoQ are
electron carriers
____ speed up the rate at which a reaction proceeds toward its final equilibrium
Enzymes
protein component of an enzyme
Apoenzyme
non-protein component of an enzyme
Cofactor
firmly attached non-protein component of an enzyme
prosthetic group
loosely attached non-protein component of an enzyme
coenzyme
apoenzyme+ cofactor =
holoenzyme
Why would an enzyme denature at high temperatures?
It is a protein. Proteins denature at adversely high temperatures.
directly competes with binding of substrate to active site
competitive inhibitor
binds enzyme at site other than active site and changes enzyme’s shape so that it becomes less active
Noncompetitive inhibitor
_____ pathways are enzyme catalyzed reactions whereby the product of one reaction serves as the substrate for the next
catabolic
____ pathways function both as catabolic and anabolic pathways
amphibolic
What are these three pathways used for?
Embden-Meyerhof pathway
pentose phosphate pathway
Entner-Duodoroffpathway
Breakdown of glucose to pyruvate
Also known as glycolysis, this is the most common pathway for glucose degradation to pyruvate in stage two of aerobic respiration and can function with or without O2
The Embden-Meyerhof Pathway
True or False: The Embden-Meyerhof Pathway has three phases.
False; it has only two phases- six-carbon and three-carbon phases
Used by soil bacteria and a few gram-negative bacteria, this pathway replaces the first phase of the Embden-Meyerhof pathway and yields 1 ATP, 1 NADPH, and 1 NADH per glucose molecule
Entner-Duodoroff pathway
Also called the hexose monophosphate pathway, this pathway can operate at same time as glycolytic pathway or Entner-Duodoroff pathway
The Pentose Phosphate Pathway
Also called citric acid cycle and Kreb’scycle
•Common in aerobic bacteria, free-living protozoa, most algae, and fungi
•Major role is as a source of carbon skeletons for use in biosynthesis
•Summary: for each acetyl-CoA molecule oxidized, generate 2 molecules of CO2, 3 molecules of NADH, one FADH2, and one GTP
Tricarboxylic Acid Cycle
True or False: All electron transport chains are found in the mitochondrial inner membrane.
False. Bacteria and Archaea do not have mitochondria
The most widely accepted hypothesis to explain oxidative phosphorylation
Chemiosmotic Hypothesis of Oxidative Phosphorylation
The theoretical maximum total yield of ATP during aerobic respiration is
38
Net gain of 146 ATP under aerobic conditions
Fat catabolism
____ hydrolyzes protein to amino acids
Protease
___ is the removal of amino group from amino acid
Deamination
_____ bacteria oxidize ammonia to nitrate
Nitrifying
A process of photosynthesis where light energy is trapped and converted to chemical energy
Light reaction
A process of photosynthesis where energy produced in the light reactions is used to reduce CO2 and synthesize cell constituents
Dark reaction
_________ is the total of all chemical reactions occurring in the cell.
Metabolism
Cells carry out three major types of work; which of the following involves nutrient uptake and waste elimination?
Chemical work. Transport work. Mechanical work. None of these.
Transport work
Cells carry out three major types of work; which of the following involves energy for cell motility and the movement of structures within cells?
Chemical work. Transport work. Mechanical work. None of these.
Mechanical work
The change in __________ is the amount of energy in a system that is available to do work.
free energy
The __________ is the electron acceptor in a redox reaction.
oxidant
The standard reduction potential of a redox reaction is a measure of the tendency of the __________ to __________ electrons.Ê
reductant; lose
True or False: The equilibrium constant for a redox reaction is called the standard reduction potential.
True
Which of the following is used as an electron carrier by living organisms?
NAD+
NADP+
ubiquinone
all of the choices
NAD+, NADP+, and ubiquinnone
True or False: The electron transport chain is based on the principle that redox couples with more positive reduction potentials will donate electrons to couples with more negative potentials.Ê
False
Which of the following is not true about enzymes?
Enzymes are catalysts that speed up reactions.
Enzymes are proteins that can be denatured by changes in pH or temperature.
Enzymes are highly specific for the substrates they react with and catalyze only one or a limited set of possible reactions with those substrates.
All of the choices are true about enzymes
All of the choices are true about enzymes
The most specific term usually used to describe a substance in a biological system that increases the rate of a reaction without being permanently changed by the reaction is a(n)
enzyme
Enzymes catalyze a reaction byÊ
decreasing the activation energy of the reaction.
"The synthesis of ATP from ADP and Pi, when coupled with an exergonic chemical reaction is called __________ phosphorylation. Ê"
substrate-level
The net gain of ATP per molecule of glucose metabolized anaerobically via the Embden-Meyerhoff pathway in prokaryotes is Ê
2
The net gain of ATP per molecule of glucose metabolized to pyruvate using Entner-Doudoroff pathway is Ê
1
The pentose phosphate pathway produces Ê
CO2.
NADPH.
glyceraldehyde
3-phosphate.
all of the choices.
The pentose phosphate produces all three
The most common pathway for conversion of glucose to pyruvate is Ê
Embden-Meyerhoff.
The pyruvate dehydrogenase complex oxidizes and cleaves pyruvate to form one CO2 and Ê
acetyl-CoA
The TCA cycle generates all of the following from each acetyl-CoA molecule oxidized except Ê
three NADH molecules.
two CO2 molecules.
one FADH2 molecule.
two ATP or GTPÊmolecules.
two ATP or GTPÊmolecules.
The major function(s) of the TCA cycle is(are) Ê
energy production and provision of carbon skeletons for biosynthesis of cell components.
The most commonly accepted hypothesis for the production of ATP that results from electron transport system is called the __________ hypothesis. Ê
chemiosmotic
The electron transport systems in eukaryotes and prokaryotes use the same electron carriers. Ê
false; they use different electron carriers`]
"In higher eukaryotes, most aerobically generated ATP is produced by Ê"
a membrane bound proton translocating ATP synthase during oxidative phosphorylation.
"In aerobic conditions, it takes __________ sugar to produce the same amount of ATP when compared to anaerobic conditions.Ê"
less
The number of ATP molecules generated per atom of oxygen that is reduced when electrons are passed from NADH or reduced FAD (FADH) to O2 is called the Ê
P/O ratio.
Fermentation does not involve the use of pyruvate and/or other organic molecules as electron acceptors.Ê
False: fermentation does involve the use of pyruvate and/or other organic molecules as electron acceptors
Which of the following can be used as electron acceptors during anaerobic respiration?Ê
nitrate sulfate carbon dioxide
nitrate, sulfate, and carbon dioxide can all be used as electron acceptors
Fatty acids are metabolized by the __________ pathway. Ê
beta-oxidation
"During breakdown of fatty acids, carbons are removed __________ at a time with each turn of the cycle, and two carbon units are released Êas __________. Ê"
two; acetyl-CoA
Amino acids are processed first by the removal of the amino group through Ê
deamination or transamination
Which of the following may be used as sources of energy by chemolithotrophs?Ê
Hydrogen gas. Reduced nitrogen compounds. Reduced sulfur compounds.
all three can be used as sources of energy by chemolithotrophs
Photosynthetic electron transport in cyanobacteria takes place Ê
on the thylakoid membranes.
Most bacterial and archaeal cells divide by
binary fission
"The cell elongates, replicates its chromosome, and separates the chromosome into the two parts of the cell, and a septum forms at midcell."
the correct order for binary fission
The actin-like protein that seems to be involved in determining cell shape is
MreB
"During cytokinesis, a critical step in septation is the assembly of the "
Z ring
Quorum sensing
is a phenomenon in which bacteria monitor their own population density.
depends on the sensing of signal protein molecules.
plays an important role in formation of biofilms by Pseudomonas aeruginosa.
All three describe quorum sensing
Which of the following can be used to isolate pure cultures of bacteria from mixtures?
spread plates streak plates pour plates
all three are methods to isolate pure cultures or bacteria
Media containing some ingredients of unknown chemical composition are called __________ media.
complex
"Mannitol salt agar (MSA) only allows the growth of halophiles (salt-loving microbes); nonhalophiles will not grow. Among the halophiles, mannitol fermenters will produce acid that turns the pH indicator yellow; mannitol nonfermenters leave the medium red. Onto MSA you inoculate a halophilic mannitol fermenter and a halophilic mannitol nonfermenter. In this case, the medium is acting as (a) __________ medium/"
differential
"Mannitol salt agar (MSA) only allows the growth of halophiles (salt-loving microbes). Among the halophiles, mannitol fermenters release acid that turns the pH indicator yellow; mannitol nonfermenters leave the medium red. Onto MSA you inoculate a halophilic mannitol nonfermenter and a nonhalophilic mannitol nonfermenter. Here the medium acts as a __________ medium. "
selective
Media in which all components and their concentration are known are called __________ media.
defined
The total number of viable microorganisms remains constant in stationary phase because
either there is a balance between cell division and cell death or there is a cessation of cell division even though the cells may remain metabolically active.
Cells may enter stationary phase because of
the depletion of an essential nutrient.
a lack of available oxygen.
the accumulation of toxic waste products.
all three may cause a cell to enter stationary phase
Which of these methods can be used to determine the number of viable microorganisms in a sample?
Light scattering in a spectrophotometer.
Measuring total cell mass.
Measuring colony forming units per ml.
Counting a known volume of cells in a hemocytometer.
Measuring colony forming units per ml.
Microorganisms are most nearly uniform in terms of chemical and physiological properties during __________ phase.
exponential
Which of the following is a reason for the occurrence of a lag phase in a bacterial growth curve?
"The cells may be old and depleted of ATP, essential cofactors, and ribosomes that must be synthesized before growth can begin."
The medium may be different from the previous growth medium so that the cells must synthesize new enzymes to use different nutrients.
The organisms may have been injured and require time to recover.
All of these are potential reasons.
All of these are potential reasons.
"If all cell components are synthesized at constant rates relative to one another, the culture is said to be in __________ growth; however, if the rates of synthesis of some components change relative to the rates of synthesis of other components, the culture is said to be in __________ growth. "
balanced; unbalanced
"Given a log phase bacterial culture with 1 x 10^6 cells per ml and a generation time of 30 minutes, how long does it take the culture to reach a density of 6.4x 10^7 cells per ml? "
3 hours
"At 4:00 p.m. a closed flask of sterile broth is inoculated with 10,000 cells. The lag phase lasts 1 hour. At 9:00 p.m. the log phase culture has population of 65 million cells. The approximate number of generations that has occurred is"
13
"At 4:00 p.m. a closed flask of sterile broth is inoculated with 10,000 cells. The lag phase lasts 1 hour. At 9:00 p.m. the log phase culture has a population of 65 million cells. The mean generation time is approximately"
20 minutes
The Archaea generally lack which of the following that are normally found in gram-negative bacteria?
Outer membrane.
A complex peptidoglycan network.
Lipopolysaccharide.
archaea lack all three features
A feature unique to some archaeal plasma membranes is that they may
consist of a lipid monolayer.
Because archaeons lack peptidoglycan in their cell walls
some have an outer layer of complex polysaccharide and some have an outer layer of protein
Archaeal membranes contain which of the following lipids?
phospholipids sulfolipids glycolipids
archaea contain all three lipids
Diglycerol tetraether lipids
are a characteristic feature of thermophilic Archaea.
"Which of the following organelles is involved in the modification, packaging, and secretion of materials? "
golgi apparatus
Receptor mediated endocytosis
"depends on formation of clathrin coated pits that pinch off and is used to internalize molecules such as hormones, growth factors, iron, and cholesterol."
The nucleolus plays a major role in synthesis of
RNA
Which is not true of viruses?
They can exist in an intracellular or extracellular phase.
They infect animal and plant cells only.
They replicate only inside host cells. They are acellular.
They infect animal and plant cells only.
A complete virus particle is called a
virion
The nucleic acids carried by viruses usually consist of
either DNA or RNA.
Which of the following is not true of viruses?
Viruses are acellular.
Viruses consist of one or more molecules of DNA or RNA enclosed in a coat of protein and sometimes in other more complex layers.
Viruses can exist in two phases: intracellular and extracellular.
Viruses replicate by binary fission.
Viruses replicate by binary fission.
"In an enveloped virus, the part of the virus including the nucleic acid genome and the surrounding protein coat but not the envelope is called the "
nucleocapsid.
Viral capsid protein subunits are called
protomers
Glycoprotein spikes protruding from the outer surface of viral envelopes function as
factors that bind to host cells.
The function of the viral protein coat is to
protect the viral genetic material and aid in the transfer of the viral genetic material between host cells.
Most enveloped viruses use the host __________ membrane as their envelope source.
plasma
Nonenveloped viruses most often gain access to eukaryotic host cells by
endocytosis
Animal viruses have been cultivated in
suitable host animals.
embryonated eggs.
tissue cultures (monolayers of animal cells).
animal viruses have been cultivated in all three
A ________ assay is most useful for determining the viability of a viral preparation?
plaque
Viroids are of economic significance because they cause disease in
plants
Which of the following diseases is (are) caused by prions?
Scrapie. Mad cow disease. Kuru and Creutzfeldt-Jakob Disease.
all three are prion caused diseases
Which of the following individuals or groups of individuals demonstrated that the transforming principle was DNA?
" Avery, MacLeod, and McCarty"
Griffith
Hershey and Chase
Watson and Crick
" Avery, MacLeod, and McCarty"
The principle of transformation was first demonstrated by which of the following individuals or groups of individuals?
" Avery, MacLeod, and McCarty"
Griffith
Hershey and Chase
Watson and Crick
Griffith
"Hershey and Chase demonstrated that when the bacteriophage T2 infected its host cell, the __________ is injected into the host but the __________ remained outside. "
DNA; protein
The genetic information in DNA is divided into units called
genes
Which of the following is true about the structure of DNA?
Purine and pyrimidine bases are attached to the 1'-carbon of the deoxyribose sugars.
Purine and pyrimidine bases are joined by phosphodiester bonds. "
Adjacent bases are stacked on top of each other, one base pair every 0.34 nm."
all of the above are true.
all of the above are true about DNA structure
Which of the following is not a pyrimidine?
adenine cytosine thymine uracil
adenine
"The two strands of a DNA molecule are __________; that is, they are oriented in opposite directions. "
antiparallel
"When a DNA molecule is replicated, the daughter molecules contain one strand of parental DNA and one strand of newly synthesized DNA; this is called __________ replication. "
semi-conservative
The chromosomes of most bacteria are comprised of
double-stranded circular molecules
During replication the 2 strands of the DNA molecule are unwound from one another by enzymes called
helicases
"The coding sequence in the DNA of __________ is normally continuous; that is, it is not interrupted by noncoding sequences. "
prokaryotes
The process by which the base sequence of all or a portion of a DNA molecule is used to direct the synthesis of an RNA molecule is called
transcription
The region at which the RNA polymerase binds is the __________ region.
promoter
"The transcribed, but not translated, sequence that is immediately upstream of the region that encodes the functional product is called the __________ region. "
leader
The unexpressed regions of split genes are called
introns
The strand of DNA for a particular gene that is copied by the RNA polymerase to form mRNA is called the __________ stran
template
Messenger RNA molecules that direct the synthesis of more than one polypeptide are said to be __________.
polycistronic
A consensus sequence in the untranslated leader sequence of a prokaryotic mRNA which serves as a ribosome binding site is called the __________ sequence.
Shine-Delgarno
The process by which the base sequence of an RNA molecule is used to direct the synthesis of a protein is called
translation.
________ molecules deliver amino acids to ribosomes during translation.
Transfer RNA (tRNA)
Which of the following is not a termination codon?
AUG UAA UAG UGA
The portion of the tRNA molecule that binds to the codon on the mRNA is called the
anticodon
What is the minimum number of aminoacyl-tRNA synthetase enzymes needed to attach amino acids to all the various tRNA molecules?
20
In __________ ribosomes can attach to the mRNA and begin translation even though transcription has not been complete
prokaryotes
The energy needed for protein synthesis is provided by the hydrolysis of
ATP and GTP
___________ in proteins includes alpha-helixes and beta-pleated sheets.
secondary structures
What are used to regulate protein folding to minimize the risk of protein mis-folding?
chaperones
A gram negative bacterium wishes to secrete a previously-folded virulence factor. Which of the following secretion systems would be used to accomplish this?
Type II SS