Final Exam Flashcards
The three basic catabolic pathways are:
Check All That Apply
A) aerobic respiration.
B) deamination.
C) polymerization.
D) anaerobic respiration.
E) fermentation.
A) aerobic respiration.
D) anaerobic respiration.
E) fermentation.
Explanation: The three basic catabolic pathways are aerobic respiration, anaerobic respiration, and fermentation. All three begin with glycolysis, and then proceed through different reactions based on the organism and the conditions.
Epinephrine:
Multiple Choice
A) inhibits the activity of lymphocytes.
B) reverses constriction of airways.
C) is an antihistamine.
D) causes desensitization.
B) reverses constriction of airways.
What type of bond is found between carbon and hydrogen in most biological molecules?
Multiple Choice
A) Hydrogen bond
B) Ionic bond
C) Covalent bond
D) Van der Waals force
C) Covalent bond
Explanation: Carbon and hydrogen form bonds by sharing electrons. Bonds that involve the sharing of electrons are covalent bonds.
All atoms in an element have the same number of protons.
A) True
B) False
A) True
Explanation: All atoms of an element have the same number of protons and will exhibit the same chemical properties. The number of neutrons may vary if there are different isotopes of the element. The number of electrons can vary as well, creating ions of that same element.
Select the number of phosphates present in a molecule of ATP.
Multiple Choice
A) 1
B) 2
C) 3
D) 4
C) 3
Explanation: ATP, or adenosine triphosphate, contains adenine, ribose sugar, and three phosphates.
When an inhibitor mimics the substrate and occupies the active site of the enzyme, this is referred to as _________blank inhibition.
Multiple Choice
A) allosteric
B) reference
C) competitive
D) noncompetitive
C) competitive
Explanation: Enzyme activity can be modified in several ways. Competitive inhibition occurs when an inhibitor occupies the active site of the enzyme and prevents the actual substrate from accessing the active site. Noncompetitive inhibition occurs when an inhibitor binds to a regulatory site on the enzyme that is separate and distinct from the active site.
During DNA replication, the _________blank strand is synthesized continuously while the _________blank strand is synthesized in a series of short fragments called Okazaki fragments.
Multiple Choice
A) 5’; 3’
B) leading; lagging
C) parallel; antiparallel
D) forward; backward
B) leading; lagging
Explanation: The leading strand is synthesized continuously in the 5’ to 3’ direction. Since DNA polymerase can only build DNA in the 5’ to 3’ direction, the lagging strand is synthesized in short fragments called Okazaki fragments which are later joined by DNA ligase.
The protein in a conjugated enzyme is referred to as the _________blank whereas the combination of the protein and the nonprotein cofactor is known as the _________blank.
Multiple Choice
A) holoenzyme; apoenzyme
B) apoenzyme; holoenzyme
C) apoenzyme; competitive enzyme
D) holoenzyme; exoenzyme
B) apoenzyme; holoenzyme
Explanation: The protein part of a conjugated enzyme is referred to as the apoenzyme. The combination of the protein enzyme (apoenzyme) plus the nonprotein cofactor(s) is called the holoenzyme.
Viruses are inactive macromolecules inside of a host cell.
A) True
B) False
B) False
Explanation: Viruses are merely inactive macromolecules outside of a host cell. However, inside of a host cell, they can take over the cellular machinery for replication.
Choose the statement that describes the first stage of phagocytosis.
Multiple Choice
A) Phagocytes form pseudopodia at the site of inflammation in order to grab the invading microbe.
B) Phagocytes move with deliberation along a gradient of stimulatory products at the site of injury.
C) Phagocytes make their way to an inflammatory site by random chance.
D) Phagocytes release substances to attack the extracellular microbe.
B) Phagocytes move with deliberation along a gradient of stimulatory products at the site of injury.
Explanation: During phagocytosis, the first step is chemotaxis of the phagocyte along a gradient of stimulatory products towards the site of inflammation or injury. Once at the scene, the phagocytic cell recognizes PAMPs on its target microbe, and after contact, pseudopodia are formed to internalize the microbe in a phagosome.
Please select those nutrients that are essential for growth, reproduction, and maintenance of a bacterial cell.
Check All That Apply
A) DNA
B) Carbon
C) Silver
D) Hydrogen
E) Oxygen
F) Phospholipids
G) Nitrogen
H) Phosphorus
I) Sulfur
B) Carbon
D) Hydrogen
E) Oxygen
G) Nitrogen
H) Phosphorus
I) Sulfur
Explanation: The essential nutrients of a bacterial cell include carbon, hydrogen, oxygen, nitrogen, phosphorus, and sulfur (CHONPS). There are others, not included among the choices, such as potassium, sodium, calcium, magnesium, chloride, and iron. While DNA and phospholipids are essential macromolecules within the bacterial cell, they aren’t considered nutrients because bacteria don’t require a supply of these premade; they synthesize them as needed.
The second and third lines of host defenses determine whether cells are self or nonself by examining cell surfaces for identifying molecular markers.
A) True
B) False
A) True
Explanation: The ability to recognize cells as self or nonself by the immune response is important in the protection of host cells while initiating an attack to clear invaders. Certain cellular components of the second and third lines of defense are able to do this by scanning for cellular markers.
A specific segment of DNA that contains the necessary code to make a protein or RNA molecule is a:
Multiple Choice
A) chromosome.
B) Z band.
C) gene.
D) VNTR.
C) gene.
Explanation: A gene is a specific segment of DNA that contains the necessary code to make a protein or RNA molecule. A gene can also be defined as the fundamental unit of heredity responsible for a given trait of an organism.
The property of some metabolic pathways that enables them to serve multiple functions in the breakdown, synthesis, and conversion of metabolites is known as:
Multiple Choice
A) anabolism.
B) catabolism.
C) parabolism.
D) amphibolism.
D) amphibolism.
Explanation: Catabolic and anabolic processes can be integrated at various points to improve efficiency. For example, the intermediate of a catabolic pathway may be used in an anabolic pathway. This ability of pathways to serve multiple functions in both catabolic and anabolic processes is known as amphibolism.
Which of the following pairs is mismatched?
Multiple Choice
A) Hay fever - type IV hypersensitivity
B) Transfusion reaction - type II hypersensitivity
C) Serum sickness - type III hypersensitivity
D) Poison ivy dermatitis - type IV hypersensitivity
E) Food allergy - type I hypersensitivity
A) Hay fever - type IV hypersensitivity
The term used to describe a gently curved bacterium is
Multiple Choice
A) spirochete.
B) vibrio.
C) coccobacillus.
D) streptobacillus.
B) vibrio.
Explanation: Vibrio is the term used to describe bacteria that are shaped like a comma, or a gently curved bacterium.
Select the major cellular targets of physical and chemical control agents.
Check All That Apply
A) Cell wall
B) Flagella
C) Cell membrane
D) Proteins
E) Microcompartments
A) Cell wall
C) Cell membrane
D) Proteins
Explanation: There are four main targets of physical and chemical control agents. These include the cell wall, the cell membrane, cellular synthetic processes, and proteins.
A permanent change in the DNA base sequence is a:
Multiple Choice
A) primer.
B) catalyst.
C) mutation.
D) methylation.
C) mutation.
Explanation: A permanent change in the base sequence of DNA is a mutation. This may be an addition or deletion or substitution of the bases.
You are preparing a solution by mixing 10 grams of glucose into distilled water. In this solution, distilled water is the:
Multiple Choice
A) solvent.
B) ion.
C) precipitate.
D) solute.
A) solvent.
Explanation: In this solution, water is the dissolving medium or solvent. Glucose is the solute. Water is the most common solvent in biological systems.
_________blank are substances that provoke a specific immune response which is so discriminating that only a single molecular fragment, called a/an _________blank, interacts with the lymphocyte’s receptor.
Multiple Choice
A) Epitopes; immunogen
B) Allergens; allograft
C) Antigens; epitope
D) Immunogens; fragment
C) Antigens; epitope
Explanation: An antigen is a substance that provokes an immune response in specific lymphocytes. The term immunogen is another term for a substance that can elicit an immune response. A lymphocyte’s capacity to discriminate differences in molecular shape is so fine that it recognizes and responds to only a portion or molecular fragment that is specifically called the epitope.
The electron transport system in bacteria is located on the _________blank and in eukaryotic cells on the _________blank.
Multiple Choice
A) plasmid; chloroplast
B) mitochondrion; cytoplasmic membrane
C) cytoplasmic membrane; mitochondrion
D) cell wall; mitochondrion
C) cytoplasmic membrane; mitochondrion
Consider the following disease scenarios, and determine the correct mode of transmission for each.
1) Vehicle
2) Biological vector
3) Parenteral
4) Direct contact
5) Droplet
6) Healthcare-associated
Match each of the options above to the items below.
A) Syphilis from unprotected sex
B) Lyme disease
C) Salmonellosis from egg salad at a picnic
D) Chickenpox from one child coughing on another
E) Hepatitis B from needle sharing
F) MRSA
1) Vehicle
C) Salmonellosis from egg salad at a picnic
2) Biological vector
B) Lyme disease
3) Parenteral
E) Hepatitis B from needle sharing
4) Direct contact
A) Syphilis from unprotected sex
5) Droplet
D) Chickenpox from one child coughing on another
6) Healthcare-associated
F) MRSA
Fever is initiated when a substance in circulation, called a _________blank, acts on the hypothalamus causing it to reset body temperature to a higher setting.
Multiple Choice
A) bacteriocin
B) transferrin
C) pyrogen
D) leukocidin
C) pyrogen
Explanation: Fever is initiated by pyrogens that act on the hypothalamus causing it to reset at a higher temperature. Exogenous pyrogens are products of infectious agents, and endogenous pyrogens are substances released by phagocytic cells.
Match the terms related to recent advances in microbiology with their proper descriptions.
A) Microbiome
B) Polymerase Chain Reaction (PCR)
C) CRISPR
D) Small RNAs
Match each of the options above to the items below.
1) These molecules were first identified in the 2000s, and appear to play critical roles in regulating what happens in the cell.
2) This term is used to refer to all of the viruses, bacteria, fungi, and protozoa that call the human body home.
3) A newer technology that allows scientists to edit genes and provides potential to treat genetic diseases.
4) Invented by Kary Mullis in the 1980s, a method used to detect and amplify tiny amounts of DNA in a sample.
A) Microbiome
2) This term is used to refer to all of the viruses, bacteria, fungi, and protozoa that call the human body home.
B) Polymerase Chain Reaction (PCR)
4) Invented by Kary Mullis in the 1980s, a method used to detect and amplify tiny amounts of DNA in a sample.
C) CRISPR
3) A newer technology that allows scientists to edit genes and provides potential to treat genetic diseases.
D) Small RNAs
1) These molecules were first identified in the 2000s, and appear to play critical roles in regulating what happens in the cell.
Explanation: In the 1980s, Kary Mullis developed the PCR technique to amplify DNA fragments. Small RNAs were discovered in the 2000s, and play a role in gene regulation in cells. In 2008, the Human Microbiome project began, with findings released in 2012. The microbiome refers to all of the microorganisms that call our bodies home. CRISPR is a gene editing tool that was developed in the mid-2010s and has enormous potential for disease treatment.
Select all of the differences between DNA and RNA to test your understanding of these nucleic acids.
Check All That Apply
A) DNA is double-stranded, whereas RNA is single-stranded.
B) DNA nucleotides contain deoxyribose, whereas RNA nucleotides contain ribose.
C) DNA contains the following nitrogenous bases: adenine (A), cytosine (C), guanine (G), and uracil (U); whereas RNA contains adenine, cytosine, guanine, and thymine.
D) There are multiple types of DNA with different functions, whereas there is only one type of RNA.
A) DNA is double-stranded, whereas RNA is single-stranded.
B) DNA nucleotides contain deoxyribose, whereas RNA nucleotides contain ribose.
Explanation: While DNA and RNA are both nucleic acids, there are some key differences between them. DNA is double-stranded whereas RNA is single-stranded. DNA nucleotides contain deoxyribose, and RNA nucleotides contain ribose. DNA contains adenine, guanine, cytosine and thymine nitrogenous bases, and RNA contains adenine, guanine, cytosine, and uracil. There is one functional type of DNA, but multiple functional types of RNA including mRNA, rRNA, tRNA, miRNA, siRNA, and ribozymes.
Select the characteristics exhibited by effective vaccines.
Check All That Apply
A) Little or no adverse side effects
B) Protect against exposure to wild-type, natural pathogens
C) Requires numerous doses or boosters
D) Stimulate either a B-cell or a T-cell response
E) Relatively long shelf life
A) Little or no adverse side effects
B) Protect against exposure to wild-type, natural pathogens
E) Relatively long shelf life
Explanation: Effective vaccines induce both cell-mediated and humoral immunity while producing little to no side effects. The fewer the doses needed, the less expensive the vaccine is for patients. Ease of administration and extended shelf life also contribute to an effective vaccine.
Diffusion is a general term referring to the net movement of atoms and molecules along a concentration gradient, from an area of low concentration to an area of high concentration.
A) True
B) False
B) False
Explanation: Diffusion refers to the movement of atoms or molecules down a concentration gradient from an area of high concentration to an area of low concentration. Because the atoms or molecules are moving down their gradient, energy is not required, and therefore diffusion is a passive process.
Which of the following represent epigenetic changes caused by a pathogen that can affect its ability to cause infection in the host?
Check All That Apply
A) Activation or inactivation of host cell DNA
B) Binding to RNAs that silence genes
C) Affect host cell DNA that is responsible for cytoskeleton organization
D) Exchange of capsule genes between pathogen and host cell
E) Secretion of endotoxin from the cell wall of a pathogen
A) Activation or inactivation of host cell DNA
B) Binding to RNAs that silence genes
C) Affect host cell DNA that is responsible for cytoskeleton organization
Explanation: Microbes have been known to turn on or shut down host DNA. They do this by binding to host cell chromatin, histones, or silencing RNAs. They also have affected the cytoskeleton, causing disorganization of the cell.
Select the statements that most accurately reflect immune dysfunction.
Check All That Apply
A) Cancer can be both a cause and an effect of immune dysfunction.
B) Hyposensitivity diseases include autoimmune disorders.
C) AIDS is a hypersensitivity disease.
D) Hypersensitivity diseases can be due to normal immune reactions targeting healthy bystander tissue.
E) Allergies are due to overreactivity of the immune system.
A) Cancer can be both a cause and an effect of immune dysfunction.
D) Hypersensitivity diseases can be due to normal immune reactions targeting healthy bystander tissue.
E) Allergies are due to overreactivity of the immune system.
Explanation: Immunopathology is the study of disease states (immune dysfunctions) associated with overreactivity or underreactivity of the immune response. Overreactivity includes forms of allergy, hypersensitivity and autoimmunity. In immunodeficiency or underreactivity diseases, immune function is incompletely developed, suppressed, or destroyed.
Reactions that use energy and synthesize building blocks into macromolecules are part of _________blank, whereas _________blank refers to cellular reactions that break larger molecules into smaller molecules and release energy.
Multiple Choice
A) anabolism; catabolism
B) anabolism; amphibolism
C) catabolism; anabolism
D) amphibolism; catabolism
A) anabolism; catabolism
Explanation: Metabolism includes anabolism, the synthesizing, energy-requiring reactions, and catabolism, the degradative reactions that release energy.
Choose the phrase that best describes the role of viral surface proteins or spikes.
Multiple Choice
A) Inject viral nucleic acid into host cell
B) Allow viruses to bind to each other
C) Enable replication of the viral nucleic acid
D) Provide means of attachment to host cell surface
E) Provide means for viruses to exchange nucleic acid
D) Provide means of attachment to host cell surface
Explanation: Many viruses have surface proteins that project outward from the capsid or envelope. These proteins provide a means for the virus to attach to a host cell, the first step in establishing an infection.
All organisms studied in microbiology must be viewed with a microscope.
A) True
B) False
B) False
Explanation: Bacteria and viruses are microscopic but some protozoans and algae are visible to the naked eye. Also, helminths, easily viewed by the naked eye in their adult forms, are studied in microbiology because they have microscopic forms in their life cycles.
Select the characteristics of biofilms that differentiate them from planktonic bacteria.
Check All That Apply
A) Microorganisms live singly and independently.
B) Microorganisms participate in quorum sensing.
C) Microorganisms secrete extracellular material, usually polysaccharide, that forms a matrix.
D) Microorganisms are readily eradicated using antibiotics.
E) Microorganisms exist as part of a diverse interdependent community.
B) Microorganisms participate in quorum sensing.
C) Microorganisms secrete extracellular material, usually polysaccharide, that forms a matrix.
E) Microorganisms exist as part of a diverse interdependent community.
Explanation: Biofilms are diverse microbial communities in which the different members exist in an interdependent relationship. Extracellular polysaccharides or proteins form a matrix that becomes the ground substance of the biofilm. Microorganisms within the biofilm participate in a type of communication referred to as quorum sensing. Microorganisms within a biofilm community are less likely to respond to antibiotics than their planktonic (independent-living) counterparts.
The time required for one complete cycle of binary fission is known as the _________blank, or generation time.
Multiple Choice
A) mating
B) mitotic
C) meiotic
D) doubling
D) doubling
Explanation: This division is referred to as doubling time, because each generation involves one bacterial cell dividing into two daughter cells.
Match the type of epidemic curve associated with each example.
1) Potato salad sits out too long at the picnic, and everyone that ate the dish suffered from vomiting later in the evening.
2) Every winter, flu spreads rapidly through the United States.
3) Typhoid Mary was an asymptomatic carrier of Salmonella, and she unknowingly transmitted the bacteria to many members of the families that she served as a cook.
Match each of the options above to the items below.
A) Point-source epidemic
B) Common-source epidemic
C) Propagated epidemic
1) Potato salad sits out too long at the picnic, and everyone that ate the dish suffered from vomiting later in the evening.
A) Point-source epidemic
2) Every winter, flu spreads rapidly through the United States.
C) Propagated epidemic
3) Typhoid Mary was an asymptomatic carrier of Salmonella, and she unknowingly transmitted the bacteria to many members of the families that she served as a cook.
B) Common-source epidemic
The theory of evolution was once a __________ that was tested repeatedly and always supported by the data collected by various scientists around the world.
Multiple Choice
A) variable
B) theorem
C) hypothesis
D) fact
C) hypothesis
Explanation: The theory of evolution was once a hypothesis. It has since been tested time and time again through the scientific method without being disproven and therefore, it was elevated to the level of a theory.
Select the type of T cell that plays a role in diminishing an immune response.
Multiple Choice
A) TREG
B) T1H
C) TC
D) T17H
A) TREG
Explanation: TREG cells play a role in dampening down immune responses. They work to prevent autoimmunity, disruption of the normal biota, and unnecessary inflammation.
Nonpolar molecules like benzene cannot be dissolved in:
Multiple Choice
A) polar fluids, like water.
B) nonpolar fluids, like alcohol.
C) the lab.
D) anything.
A) polar fluids, like water.
Enterovirus is a properly written genus designation for a group of viruses including poliovirus and coxsackievirus.
A) True
B) False
A) True
Explanation: The name of a viral genus is capitalized and written in italics.
Match the technologies with the statements that most accurately describe them to test your understanding how microorganisms are useful in society today.
A) Bioremediation
B) Genetic Engineering
C) Biotechnology
Match each of the options above to the items below.
1) Technology that applies the power of microbes toward the manufacture of industrial products, foods, and drugs.
2) Newer technology that manipulates the genetics of microbes, plants and animals to create new products and genetically modified organisms (GMOs).
3) Process that involves the introduction of microbes into the environment to restore stability or to clean up toxic pollutants.
A) Bioremediation
3) Process that involves the introduction of microbes into the environment to restore stability or to clean up toxic pollutants.
B) Genetic Engineering
2) Newer technology that manipulates the genetics of microbes, plants and animals to create new products and genetically modified organisms (GMOs).
C) Biotechnology
1) Technology that applies the power of microbes toward the manufacture of industrial products, foods, and drugs.
Explanation: Although humans have been harnessing the work of microorganisms for thousands of years (bread making, alcohol production, special cheeses), new technologies have arisen recently to expand their use. Biotechnology is a broad field of science that takes advantage of microbes’ abilities to create industrial products, foods, and drugs. Genetic engineering, an area of biotechnology, has permitted the genetic alteration of microbes and other organisms to create genetically modified organisms (GMOs) with unique and desirable traits. Examples include nutrient-rich foods and herbicide-resistant plants. Bioremediation has allowed microbes to use their own metabolic traits to clean up various wastes in human society, such as massive oil spills.
Which of the following would be used to identify an unknown bacterial culture that came from a patient in the intensive care unit?
Multiple Choice
A) Gray’s Anatomy
B) Bergey’s Manual of Determinative Bacteriology
C) The Physician’s Desk Reference
D) Bergey’s Manual of Systematic Bacteriology
B) Bergey’s Manual of Determinative Bacteriology
Although both aerobic respiration and anaerobic respiration utilize glycolysis, the Krebs cycle, and an electron transport system, _________blank respiration uses O2 as the final electron acceptor at the end of the electron transport system, whereas _________blank respiration uses an inorganic molecule other than O2 as the final electron acceptor.
Multiple Choice
A) aerobic; fermentative
B) aerobic; anaerobic
C) fermentative; aerobic
D) anaerobic; aerobic
B) aerobic; anaerobic
Explanation: In aerobic respiration, oxygen gas (O2) is the final electron acceptor at the end of the electron transport system. In anaerobic respiration, an inorganic molecule other than O2 is the final electron acceptor. An example of a common electron acceptor used in anaerobic respiration is nitrate (NO3−).
Choose the phrase that best describes photosynthesis.
Multiple Choice
A) A process which uses light energy to fuel anabolic reactions such as the assembly of large polysaccharides
B) A process which harvests light energy and converts it to chemical energy, which is used to split glucose into two molecules of pyruvic acid
C) A process which harvests light energy and converts it to chemical energy (ATP and NADPH) that is then used to “fix” or transform CO2 into organic compounds such as sugars
D) A process which occurs in plants and converts solar energy to sugars
C) A process which harvests light energy and converts it to chemical energy (ATP and NADPH) that is then used to “fix” or transform CO2 into organic compounds such as sugars
Explanation: Photosynthesis is a process which uses chlorophyll pigments to capture solar energy and convert it to chemical energy (ATP and NADPH). This chemical energy is then used to reduce CO2 to form organic compounds such as sugars. In the process, water is split and O2 gas is released, and CO2 gas is utilized.
Some strains of human papillomavirus (HPV) can cause cellular changes that lead to the development of cervical cancer. Infections by such oncogenic viruses are known as:
Multiple Choice
A) latent infections.
B) persistent infections.
C) chronic infections.
D) transforming infections.
D) transforming infections.
Explanation: The effect on cells by cancer-inducing viruses is termed transformation because they “transform” the cell from a normal cell to a cell with an abnormally increased rate of growth.
The chemical in which energy is stored in cells is called:
Multiple Choice
A) cAMP.
B) AMP.
C) ATP.
D) cADP.
C) ATP.
Explanation: The most readily available energy storage molecule in cells is ATP (adenosine triphosphate). The bonds between the phosphates are high-energy bonds, and this energy is easily released when these bonds are broken.
Salting of meat prior to the development of refrigeration technology was an example of using osmotic pressure to control microbial spoilage of this food product.
A) True
B) False
A) True
Explanation: Salting of meat and fish, as well as sugaring of fruit, are examples of osmotic pressure methods of microbial control.
Choose the statement that best describes the role of the Calvin cycle in photosynthesis.
Multiple Choice
A) The Calvin cycle is a light-capturing series of reactions that convert light energy to chemical energy.
B) The Calvin cycle is the “synthesis” part of photosynthesis, the set of reactions that actually convert CO2
to organic carbon compounds.
C) The Calvin cycle splits water and releases the electrons that are used to reduce CO2.
D) The Calvin cycle is synonymous with the light-dependent reactions of photosynthesis.
B) The Calvin cycle is the “synthesis” part of photosynthesis, the set of reactions that actually convert CO2
to organic carbon compounds.
Explanation: The Calvin cycle is actually the “synthesis” part of photosynthesis, in which CO2 is reduced to form organic compounds. It is synonymous with the light-independent reactions.
Alpha helices and beta pleated sheets are examples of the __________ level of protein structure.
Multiple Choice
A) tertiary
B) secondary
C) primary
D) quaternary
B) secondary
Explanation: There are four levels of protein structure. Alpha helices and beta pleated sheets are two different forms of secondary structure, which form due to hydrogen bonding between functional groups on the amino acids that make up the primary chain.
Select all of the sites where normal microbiota have been definitively found in humans.
Check All That Apply
A) Brain
B) Mouth
C) Liver
D) Throat
E) Large intestine
F) Skin
G) Vagina
B) Mouth
D) Throat
E) Large intestine
F) Skin
G) Vagina
Explanation: The mouth, throat (upper respiratory tract), large intestine, skin, and vagina all have normal microbiota. The brain and liver do not appear to have normal microbiota, although microbial DNA has been detected in the brain. This information may continue to change as the Human Microbiome Project progresses.
Choose the statement that indicates how cytopathic effects are detected.
Multiple Choice
A) Performing biochemical tests on infected cells
B) Performing immunological tests on infected cells
C) Growing infected cells in a variety of different media
D) Examining infected cells with a microscope
D) Examining infected cells with a microscope
Explanation: Cytopathic effects (CPEs) indicate viral damage to a cell. In order to detect cytopathic effects, the infected cells must be examined microscopically. Examples of changes include size and shape alterations, inclusion bodies, and the fusion of multiple host cells into one large cell (syncytium).
Transfusion of the wrong blood type can cause:
Multiple Choice
A) recipient antibody activation of the complement cascade to attack the RBCs.
B) fever and anemia.
C) systemic shock and kidney failure.
D) massive hemolysis of the donor RBCs.
E) All of the choices are correct.
E) All of the choices are correct.
Identify the process or environment in this list that is not affected by microorganisms.
Multiple Choice
A) Oxygen cycles
B) Recycling of dead organisms
C) All of these choices have microbial involvement.
D) Human health
C) All of these choices have microbial involvement.
Match the terms to their correct descriptions to review the types of carrier states.
1) Incubating carrier
2) Passive carrier
3) Convalescent carrier
4) Chronic carrier
5) Asymptomatic carrier
Match each of the options above to the items below.
A) Infected, but shows no symptoms of disease
B) Spreads the infectious agent before the appearance of the first symptoms
C) Recuperating patients without symptoms; may shed viable microbes
D) Shelters the infectious agent in a latent form for a long period after recovery
E) Healthcare workers who accidentally transfer pathogens to patients
1) Incubating carrier
B) Spreads the infectious agent before the appearance of the first symptoms
2) Passive carrier
E) Healthcare workers who accidentally transfer pathogens to patients
3) Convalescent carrier
C) Recuperating patients without symptoms; may shed viable microbes
4) Chronic carrier
D) Shelters the infectious agent in a latent form for a long period after recovery
5) Asymptomatic carrier
A) Infected, but shows no symptoms of disease
Explanation: When describing carrier states, it is important to first consider if the carrier is infected themselves. If they are not infected, they are passive carriers that simply transmit the organism through handling of patients or the patient’s environment. If they are infected, what stage of the infection are they in? Incubation period or the convalescent (recovering) period? Do they show signs and symptoms of infection, or are they asymptomatic carriers able to transmit the infection (such as many cases of gonorrhea and HPV)? Have they already recovered themselves but still harbor and shed the agent, such as with tuberculosis or typhoid fever?
Enzymes act as catalysts to lower what aspect of a chemical reaction?
Multiple Choice
A) Activation energy
B) Binding site availability
C) Product concentration
D) Noncompetitive inhibitor status
A) Activation energy
Explanation: Enzymes are catalysts that reduce the activation energy of a chemical reaction. This is the certain amount of energy needed to initiate a reaction. Enzymes help overcome this resistance.
Select the physical methods of microbial control.
Check All That Apply
A) Moist heat
B) Phenolics
C) Cold
D) UV radiation
E) Halogens
F) Osmotic pressure
A) Moist heat
C) Cold
D) UV radiation
F) Osmotic pressure
Explanation: The six methods of physical control of microorganisms include heat, cold, radiation, filtration, desiccation, and osmotic pressure. Halogens and phenolics are both groups of chemicals that can be used in control.
Which of the following is a macromolecule that assembles into bilayers?
Multiple Choice
A) Carbohydrate
B) Nucleic acid
C) Protein
D) Phospholipid
D) Phospholipid
Select all of the agents that will kill a microbial pathogen or completely inactivate its ability to cause disease.
Check All That Apply
A) Bacteristat
B) Fungistat
C) Virucide
D) Germicide
E) Sporicide
C) Virucide
D) Germicide
E) Sporicide
Explanation: Any agent labeled “–cidal” will kill the target organism. A bactericidal chemical will kill bacteria. A chemical labeled as bacteriostatic will not kill, but will inhibit the growth of the bacteria. The root “–static” means to stop or inhibit.
Endospores are reproductive structures produced by multiple bacterial cell divisions, with one vegetative cell producing many endospores.
A) True
B) False
B) False
Explanation: Endospores are not reproductive structures. One vegetative cell will form one endospore. When the spore is released, the vegetative cell (sporangium) is lysed. When the endospore germinates, it will form one vegetative cell.
What will be the immediate action of an allergen when it enters the body for a second time?
Multiple Choice
A) Binding of allergen to adjacent IgE binding sites on mast cells and basophils
B) Degranulation
C) Prostaglandins cause vasodilation and increased vascular permeability
D) Histamine acts on smooth muscle
E) Binding of IgE by the Fc region to mast cells and basophils
A) Binding of allergen to adjacent IgE binding sites on mast cells and basophils
A chemiclave is a piece of equipment that uses what antimicrobial agent for the purpose of sterilization?
Multiple Choice
A) Hydrochloric acid
B) Ethylene oxide
C) Silver nitrate
D) Carbon dioxide
B) Ethylene oxide
Explanation: Ethylene oxide can be used in a chemiclave. Such gas sterilization can be used to sterilize items that would be damaged by heat or liquids. It is used to sterilize plastics and a large variety of prepackaged medical devices, surgical supplies, syringes, and plastic lab supplies such as petri dishes and test tubes. Ethylene oxide can also be used to disinfect some dried foods, spices, and drugs. It is not used to sterilize bacterial media or milk and dairy products.
Select the cell counting methods that enable only living cells to be counted.
Check All That Apply
A) Viable plate count
B) Direct cell count
C) Flow cytometry
D) Coulter counter
E) Turbidometry
A) Viable plate count
C) Flow cytometry
Explanation: While all of these methods can be used to count bacterial cells, two of them enable counting of only living cells. The viable plate count requires the growth of the cells to be counted, and thus counts only living cells. Flow cytometry can be adjusted to differentiate between living and dead cells, and this makes it possible to count only living cells. Direct cell counts, the Coulter counter, and turbidometry are unable to distinguish between living and dead cells, and thus both are counted.
Cationic detergents are surface active agents, also known as _________blank, which damage bacteria by binding bacterial surface proteins and disrupting _________blank.
Multiple Choice
A) surfactants; cell membranes
B) peroxides; capsules
C) aqueous solutions; flagellar action
D) tinctures; ribosomes
A) surfactants; cell membranes
Explanation: Cationic detergents are surfactants that disrupt the cell membranes of bacteria.
Immunopathology is defined as:
Multiple Choice
A) the study of immune imbalance, whether hyper- or hypoactivity.
B) the study of AIDS.
C) the study of autoimmune diseases.
D) the study of immunodeficiencies.
A) the study of immune imbalance, whether hyper- or hypoactivity.
The ability of a nonpathogen or weakly pathogenic microorganism to cause disease primarily in an immunocompromised host is termed a/an _________blank infection.
Multiple Choice
A) pathogenic
B) opportunistic
C) virulent
D) antagonistic
B) opportunistic
Explanation: If a host’s immune system is sufficiently compromised, a nonpathogenic or weakly pathogenic microorganism may be able to cause disease. These are often called opportunistic infections.
The sum total of the genetic material of a cell is its:
Multiple Choice
A) transcriptome.
B) proteose.
C) genome.
D) genes.
C) genome
Explanation: The genome is the sum total of the genetic material of a cell. It includes DNA found in the nucleus or nucleoid region of cells as well as DNA in other locations such as mitochondria, chloroplasts, or plasmids.
Select all of the phrases below that represent the structure and function of enzymes.
Check All That Apply
A) Composed of protein
B) Increase the rate of chemical reactions
C) Are used up in chemical reactions
D) High concentrations are necessary for activity
E) Activity is affected by temperature and pH
F) Activity is affected by regulatory mechanisms
G) Become incorporated into the reaction product
H) Have active sites with which substrates interact
I) Enzyme increase the activation energy of a reaction
A) Composed of protein
B) Increase the rate of chemical reactions
E) Activity is affected by temperature and pH
F) Activity is affected by regulatory mechanisms
H) Have active sites with which substrates interact
Explanation: Enzymes are the critical molecules which enable and control cellular metabolism. Enzymes are composed of protein. As such, their activity is affected by temperature and pH. Enzymes increase the rate of chemical reactions within the cell and their activity can be adjusted by a variety of regulatory mechanisms. Enzymes are much larger than the substrates with which they interact. Generally, the substrate must fit into the active site of the enzyme. Enzymes work by lowering the activation energy of a reaction. They are recycled and are not used up in a reaction, so they can operate at very low concentrations. They are not incorporated into the reaction products.
Select the statement that accurately characterizes ATP.
Multiple Choice
A) It is generated by a catabolic reaction.
B) It contains the nitrogen base cytosine.
C) It contains three phosphate molecules.
D) It contains five high-energy bonds.
C) It contains three phosphate molecules.
Explanation: ATP contains adenosine and three phosphate molecules. The synthesis of ATP involves the formation of a bond between ADP and a phosphate group, an anabolic reaction.
Select all of the statements that characterize obligate saprobes.
Check All That Apply
A) They live in a host.
B) They live on a host.
C) They feed off of dead organic matter in water.
D) They feed off of dead organic matter in soil.
E) They lack enzymes to degrade organic matter.
C) They feed off of dead organic matter in water.
D) They feed off of dead organic matter in soil.
Explanation: Obligate saprobes must live off of dead organic matter in soil or water, and they cannot adapt to a host.
What component provides for a stronger cell wall structure in gram-positive cells in comparison to gram-negative cells?
Multiple Choice
A) Outer membrane
B) Lipopolysaccharide
C) Teichoic acids
D) Phospholipids
E) Thick peptidoglycan layer
E) Thick peptidoglycan layer
Explanation: It is the thickness of the peptidoglycan layer that makes gram-positive cell walls stronger than gram-negative cells walls. The teichoic acids in gram-positive cell walls do not significantly contribute to the strength of the cell wall. Both cell types have phospholipids in their cell membrane. Gram-positive cells do not have an outer membrane or lipopolysaccharide.
What represents a nonionizing form of radiation, often used for disinfection purposes?
Multiple Choice
A) Cathode rays
B) UV radiation
C) Gamma rays
D) X rays
B) UV radiation
Explanation: Ionizing radiation such as gamma radiation is used for cold sterilization of a variety of items, including plastics, pharmaceuticals, and foods. Nonionizing radiation, also known as UV light, doesn’t penetrate well, but can readily be used for disinfection purposes.
How may this tree have been drawn differently prior to genetic analysis of ribosomal RNA and the subsequent development of the three domain classification system?
Multiple Choice
A) The organisms listed in Domain Bacteria and Domain Archaea would be coming off the same branch, rather than Domain Archaea coming off the same branch as Domain Eukarya.
B) The organisms listed in Domain Bacteria and Domain Eukarya would be coming off the same branch, rather than Domain Archaea coming off the same branch as Domain Eukarya.
C) The organisms listed in all three domains would be separately coming off the ancestral cell line box.
D) There would be no significant changes to the branching of this tree.
A) The organisms listed in Domain Bacteria and Domain Archaea would be coming off the same branch, rather than Domain Archaea coming off the same branch as Domain Eukarya.
Explanation: Originally, archaea and bacteria were part of the same kingdom (Monera) because of their structural similarities.
Solutions of antimicrobial chemicals dissolved in pure water are termed tinctures, while those dissolved in pure alcohol are termed aqueous.
A) True
B) False
B) False
Explanation: The opposite is true. Solutions of antimicrobial chemicals dissolved in pure water are termed aqueous, while those dissolved in pure alcohol are termed tinctures.
Select the electron carriers used by cells.
Check All That Apply
A) Glucose
B) NAD
C) FAD
D) ATP
E) NADP
B) NAD
C) FAD
E) NADP
Explanation: The electron carriers used by cells include NAD (nicotinamide adenine dinucleotide), FAD (flavin adenine dinucleotide), and NADP (nicotinamide adenine dinucleotide phosphate).
The study of the frequency and distribution of a disease in a defined population is
Multiple Choice
A) pathology.
B) clinical microbiology.
C) epidemiology.
D) immunology.
E) medicine.
C) epidemiology.
Select the statements that are true of inducible operons to test your understanding of the differences between inducible and repressible operons.
Check All That Apply
A) Inducible operons often contain genes for enzymes that function in catabolic processes.
B) Inducible operons are usually in the “turned on” state and are ‘turned off’ when not needed.
C) The inducer is often the product of the enzymes encoded.
D) Inducible operons will be “turned on” in the presence of the substrate and turned off in its absence.
E) The lac operon is an example of an inducible operon.
A) Inducible operons often contain genes for enzymes that function in catabolic processes.
D) Inducible operons will be “turned on” in the presence of the substrate and turned off in its absence.
E) The lac operon is an example of an inducible operon.
Explanation: Inducible operons usually encode enzymes required for catabolic processes. This means that the enzymes necessary for the catabolism of that substrate will only be produced when that substrate is present. These operons are in the “off” state when the substrate is absent. The lac operon is an example of an inducible operon.
Match the bacterial shapes with the appropriate description.
A) Bacillus
B) Coccus
C) Spirillum and spirochete
Match each of the options above to the items below.
1) Spherical cell
2) Cylindrical or rod-shaped cell
3) Spiral or helical-shaped cell
A) Bacillus
2) Cylindrical or rod-shaped cell
B) Coccus
1) Spherical cell
C) Spirillum and spirochete
3) Spiral or helical-shaped cell
Explanation: Spherical bacterial cells are called cocci (coccus, singular). A cylindrical or rod-shaped cell is referred to as a bacillus. A spiral or helical-shaped cell is called a spirillum or a spirochete.
The clear fluid found in whole blood in which the cells are suspended is called _________blank; however, when the clotting factors are removed, it is now called _________blank.
Multiple Choice
A) whole blood; serum
B) serum; plasma
C) plasma; serum
D) plasma; whole blood
C) plasma; serum
Explanation: Plasma is the fluid that suspends the cells in whole blood; when clotting factors are removed, the fluid is now called serum.
Koch’s postulates help to determine:
Multiple Choice
A) correlation.
B) predisposition.
C) randomization.
D) causation.
D) causation.
The relative ability of a microbe to establish itself in a host and cause disease is referred to as:
Multiple Choice
A) opportunism.
B) exogenous.
C) virulence.
D) variance.
C) virulence.
Explanation: Virulence is a very closely related term to the word “pathogenicity” and indicates a microbe’s relative ability to cause disease.
Colonization will result in infection and disease if any pathogenic microbes are present.
A) True
B) False
B) False
Explanation: Potential pathogens can simply exit the body without multiplying and causing infection.
