MICRO TEST 4

Most bacteria grow best at pH 1. 5. 7. 9. 14.

7

Which concentration of ethanol is the most effective bactericide? 100% 70% 50% 40% 30%

70%

The antibodies found in mucus, saliva, and tears are IgG. IgM. IgA. IgD. IgE.

IgA

In the last segment of the animation, when does the first epidemic occur? April of year four January of year four September of year three January of year three March of year two

January of year three

How are superantigens different from other types of exotoxins? Superantigens are comprised of two functional domains. Superantigens cause an overstimulation of the host immune system. Superantigens must be endocytosed into a target cell before becoming active. Superantigens only act against host neurons.

Superantigens cause an overstimulation of the host immune system.

Which of the following defense systems would be involved in eliminating virally-infected cells? Phagocytosis T lymphocytes Complement system Humoral immunity

T lymphocytes

Which type of T cell is involved in activating macrophages and stimulating development of cytotoxic T cells? TH1 cells TH2 cells Treg cells CD8+ T cells

TH1 cells

Microbes are associated with life-sustaining benefits as well as life-threatening diseases. True False

TRUE

How do phagocytes communicate to other cells what they have captured? They engulf virally infected cells. They present antigens from engulfed foreign cells. They spread viruses to other cells.

They present antigens from engulfed foreign cells.

Gluteraldehydes are among the most effective chemical control agents because they __________. are useful in preserving food are relatively safe, yet considered a sterilizing agent are oligodynamic act as surfactants

are relatively safe, yet considered a sterilizing agent

Bacteria that can grow in the presence or absence of oxygen (O2) are called __________. obligate anaerobes microaerophiles facultative anaerobes obligate aerobes

facultative anaerobes

All cells possess a cell wall. True False

false

Salmonella, Shigella, Yersinia, and Serratia are all pathogens. gram-positive aerobic cocci. gram-negative facultatively anaerobic rods. endospore-forming bacteria. fermentative.

gram-negative facultatively anaerobic rods.

Biological transmission differs from mechanical transmission in that biological transmission requires an arthropod. requires direct contact. works only with noncommunicable diseases. involves fomites. involves specific diseases.

involves specific diseases.

The DNA found in most bacterial cells is surrounded by a nuclear membrane. is found in multiple copies. is circular in structure. is linear in structure. utilizes histones for chromosomal packaging.

is circular in structure.

In the figure, the path labeled (2) is the flow of energy. water. electrons. glucose. protons.

protons

Consider a Kirby-Bauer disk-diffusion assay. If you put penicillin and streptomycin disks adjacent to one another, the zone of inhibition is greater than that obtained by either disk alone. This is an example of __________. mutual exclusion RNA interference synergism antagonism

synergism

The following steps occur during multiplication of retroviruses. Which is the fourth step? attachment synthesis of +RNA synthesis of double-stranded DNA uncoating penetration

synthesis of double-stranded DNA

What is the correct sequence of events for activation of a B cell by a T-dependent antigen? The B cell binds to a cytokine and then interacts with the TH cell. This causes the B cell to bind the antigen, and then the B cell is activated. The T cells binds to an antibody on the B cell. The T cell secretes cytokines. The B cell binds the antigen. The B cell is activated by binding to the antigen. Identical repeating subunits on the antigen bind to many of the antibodies on the surface of the B cell. This activates the B cell. (1) Immunoglobulin receptors on the B cell recognize and bind the antigen. (2) An antigen fragment in complex with MHC class 2 is displayed on the B cell's surface. (3) The MHC-antigen complex binds a receptor on a TH cell. (4) The TH cell secretes cytokines that activate the B cell.

(1) Immunoglobulin receptors on the B cell recognize and bind the antigen. (2) An antigen fragment in complex with MHC class 2 is displayed on the B cell's surface. (3) The MHC-antigen complex binds a receptor on a TH cell. (4) The TH cell secretes cytokines that activate the B cell

Which statements are true? 1-Electron carriers are located at ribosomes. 2-ATP is a common intermediate between catabolic and anabolic pathways. 3-ATP is used for the long-term storage of energy and so is often found in storage granules. 4-Anaerobic organisms are capable of generating ATP via respiration. 5-ATP can be generated by the flow of protons across protein channels. 1, 2, 3 2, 3, 5 1, 3, 4 2, 4, 5 All of the answers are correct.

2, 4, 5

Place the steps of the Gram stain in the correct order. 1-Alcohol-acetone 2-Crystal violet 3-Safranin 4-Iodine 1-2-3-4 2-4-1-3 1-3-2-4 2-1-4-3 4-3-2-1

2-4-1-3

According to the animation, surgical infections account for what percentage of nosocomial infections? 20% 15% 8% 11% 40%

20%

Which of the following places these items in the correct order for DNA-virus replication? 1. Maturation 2. DNA synthesis 3. Transcription 4. Translation 2; 3; 4; 1 4; 3; 2; 1 1; 2; 3; 4 3; 4; 1; 2 4; 1; 2; 3

2; 3; 4; 1

A microbe reproduces by binary fission every 20 minutes under favorable conditions. How long would 10 generations take and how many bacteria would be present if all the conditions were just right? 3 hours 20 minutes, producing 1,024 bacteria 2 hours and 10 minutes, producing 1,048,576 bacteria 18 hours and 40 minutes, producing 1 million bacteria 24 hours, producing 262,144 bacteria

3 hours 20 minutes, producing 1,024 bacteria

Thirty-six colonies grew in nutrient agar from 1.0 ml of undiluted sample in a standard plate count. How many cells were in the original sample? 4 9 18 36 72

36

Most fungi grow best at pH 1. 5. 7. 9. 14.

5

In the figure, what is the thermal death time? 120 minutes 100°C The answer cannot be determined. 150°C 60 minutes

60 minutes

You have a small gene that you wish replicated by PCR. After 3 replication cycles, how many double-stranded DNA molecules do you have? 2 4 8 16 thousands

8

Which of the following scenarios is an example of bacterial motility? A bacterium traveling through the air from a sneeze A bacterium being removed from the skin during hand washing A bacterium moving towards a food source

A bacterium moving towards a food source

Which of the following would be considered a vector? Water containing bacteria from fecal matter. A fly carrying disease from fecal matter to food. Water droplets that come from a sneeze from an infected individual. Saliva that is transmitted between individuals during kissing.

A fly carrying disease from fecal matter to food.

Which of the following would be an example of disease transmission via INDIRECT contact? A student sneezes on her test booklet. The instructor grades it and catches her cold. A tick that is infected with Lyme disease bites a hiker, and the hiker gets Lyme disease. Mr. Smith sneezes on an airplane, and the person sitting beside him catches his cold. A restaurant worker has diarrhea caused by Norovirus. He fails to wash his hands adequately before preparing the salad, and his customers get sick.

A student sneezes on her test booklet. The instructor grades it and catches her cold.

All of the following are used by bacteria to attach to host cells EXCEPT M protein. capsules. ligands. fimbriae. A-B toxins.

A-B toxins

Which of the following is NOT part of the passive transport process? plasma membrane concentration gradient ATP transporter proteins aquaporins

ATP

Which of the following is true of aerobic respiration compared to anaerobic respiration? Aerobic respiration uses oxygen as a final hydrogen acceptor, whereas anaerobic respiration uses an inorganic molecule other than oxygen as the final electron acceptor. Aerobic respiration is less efficient than all forms of anaerobic respiration, producing less ATP and largerend-products. Aerobic respiration and anaerobic respiration both require oxygen as a final electron acceptor. Aerobic respiration uses oxygen as a final electron (hydrogen) acceptor, whereas anaerobic respiration uses an organic molecule.

Aerobic respiration uses oxygen as a final hydrogen acceptor, whereas anaerobic respiration uses an inorganic molecule other than oxygen as the final electron acceptor.

Genetic change in bacteria can be brought about by transduction. mutation. conjugation. transformation. All of the answers are correct.

All of the answers are correct.

Scientists like to use fluorescent proteins for various types of recombinant DNA procedures. You have a very small amount of the gene for a fluorescent protein. You'd like to make a fluorescent bacterium (!). Which of the following represents the correct sequence of procedures that you would use? Amplify the gene using PCR. Insert the gene into a plasmid vector. Transform the vector into the bacteria. Insert the gene into a plasmid vector. Amplify the gene using PCR. Transform the vector into the bacteria. Transform the vector into the bacteria. Amplify the gene using PCR. Insert the gene into a plasmid vector. Amplify the gene using PCR. Transform the vector into the bacteria. Insert the gene into a plasmid vector.

Amplify the gene using PCR. Insert the gene into a plasmid vector. Transform the vector into the bacteria.

Which of the following would be an example of an infection initiated via the parenteral route? An individual contracts hepatitis B from an accidental stick with a contaminated needle. An individual contracts a gastrointestinal infection by consuming contaminated water. An individual contracts a hookworm infection as a result of walking around outside barefoot. An individual contracts gonorrhea as a result of unprotected sex.

An individual contracts hepatitis B from an accidental stick with a contaminated needle.

Which of the following would be an example of an infection initiated via the parenteral route? An individual contracts hepatitis B from an accidental stick with a contaminated needle. An individual contracts gonorrhea as a result of unprotected sex. An individual contracts a gastrointestinal infection by consuming contaminated water. An individual contracts a hookworm infection as a result of walking around outside barefoot

An individual contracts hepatitis B from an accidental stick with a contaminated needle.

Which of the following would be considered a fomite? A fly Contaminated water An infected toy A tick

An infected toy

Which of the following is NOT a domain in the three-domain system? Eukarya Animalia Bacteria Archaea

Animalia

How might a patient who is not being treated with an antibiotic still be exposed to an antibiotic? Visitors currently being treated with antibiotics can pass them on to the patient. Antibiotics can be used in aerosols, thereby entering the environment. Health care workers being treated with antibiotics may pass the antibiotic on to the patient.

Antibiotics can be used in aerosols, thereby entering the environment.

Who is credited with first observing microorganisms? Carolus Linnaeus Anton van Leeuwenhoek Robert Koch Louis Pasteur Robert Hooke

Anton van Leeuwenhoek

Which domain of the A-B toxin binds to cell surface receptors on the host cell? Both the A and B domains have the ability to bind to cell surface receptors. B domain A domain A-B toxins do not bind to cell surfaces.

B domain

__________________ stimulated with ___________ differentiate into __________, which secrete antibodies into the bloodstream. Plasma cells, antigen, B-cells B-cells, antigen, plasma cells Phagocytes, antigen, B-cells Antigen, plasma cells, B-cells

B-cells, antigen, plasma cells

The biosafety level (BSL) for a clinical microbiology laboratory working with potentially airborne pathogens, such as tuberculosis bacteria, is BSL-3. BSL-4. BSL-2. BSL-1.

BSL-3

What type of nosocomial infection is likely to arise from intravenous catheterizations? Cutaneous Bacteremia Surgical Lower respiratory Urinary tract

Bacteremia

In what way are semisynthetic penicillins and natural penicillins alike? Both are bactericidal. Both are based on β-lactam. Both are resistant to penicillinase. Both are resistant to stomach acids. Both are broad spectrum.

Both are based on β-lactam.

A disk-diffusion test using Staphylococcus gave the following results: Disinfectant Zone of inhibition (mm) A 0 B 2.5 C 10 D 5

C.10

In the classical pathway, which of the following directly activates cellular responses? C3a and C5a C3b C3a, C5a, and C5bC6C7 C4aC2bC3b C2aC4b C5bC6C7

C3a, C5a, and C5bC6C7

Which complement protein is used as an opsonin? C5b C2a C3b C7 C3a C4a

C3b

UUA leucine UAA nonsense GCA alanine AAU sparagine AAG lysine UGC cysteine GUU valine UCG, UCU serine Refer to the table The anticodon for valine is CTT. CAA. GUU. GTA. CUU.

CAA

Which of the following destroys virus-infected cells? Treg CTL B cells dendritic cells TH

CTL

Which of the following is NOT an enteric? Escherichia Enterobacter Shigella Campylobacter Salmonella

Campylobacter

The structures illustrated in the figure are composed of DNA. Capsomeres. DNA or RNA. RNA. Capsids.

Capsomers

How can capsules enable bacteria to evade the immune system? Capsules block the complement biding sites on the surface of the pathogen. Capsules can bind up IgA, rendering it inactive. A capsule is a superantigen that distracts the immune system.

Capsules block the complement biding sites on the surface of the pathogen.

Which of the following can release histamines? Invading bacterial cells Wood from a splinter Cells from damaged tissues and the complement pathway Cells from damaged tissues The complement system

Cells from damaged tissues and the complement pathway

Which of the following statements concerning cellular immunity is FALSE? T cells respond to antigens when the antigens bind to receptors on their surface. The thymus is necessary for development of cells involved in cellular immunity. The lymphocytes involved with cellular immunity are found primarily in lymphoid organs and blood. Cellular immunity involves cells that recognize antigens and make specific antibodies against them.

Cellular immunity involves cells that recognize antigens and make specific antibodies against them.

What complement result involves the use of phagocytes? Cytolysis Opsonization Chemotaxis and opsonization Chemotaxis

Chemotaxis and opsonization

Which of the following would you likely see on the surface of a human dendritic cell following phagocytosis of a bacterium? Class II MHC with engulfed bacterial antigens Class II MHC with dendritic cell antigens Class I MHC with dendritic cell antigens and Class II MHC with engulfed bacteria Class I MHC with dendritic cell antigens

Class I MHC with dendritic cell antigens and Class II MHC with engulfed bacteria

What would a virally infected skin epithelial cell have on its cell surface? Class II MHC with liver cell antigens Class II MHC with macrophage antigens Class I MHC with skin cell antigens Class II MHC with viral antigens

Class I MHC with skin cell antigens

Which of the following correctly matches enzyme components with their correct definition and/or function? Cofactors are the protein components of enzymes. Apoenzymes are typically inorganic molecules, such as iron, zinc, or magnesium. Coenzymes are the organic cofactors important to enzyme activity. Apoenzymes are the nonprotein component of an enzyme.

Coenzymes are the organic cofactors important to enzyme activity.

Which of the following is considered a major category of transmission of disease? Contact, vehicle, and vector transmission Vector transmission Contact transmission Vehicle transmission

Contact, vehicle, and vector transmission

During a six-month period, 239 cases of pneumonia occurred in a town of 300 people. A clinical case was defined as fever 39°C lasting >2 days with three or more symptoms (i.e., chills, sweats, severe headache, cough, aching muscles/joints, fatigue, or feeling ill). A laboratory-confirmed case was defined as a positive result for antibodies against Coxiella burnetii. Before the outbreak, 2000 sheep were kept northwest of the town. Of the 20 sheep tested from the flock, 15 were positive for C. burnetii antibodies. Wind blew from the northwest, and rainfall was 0.5 cm compared with 7 to 10 cm during each of the previous three years. The etiologic agent of the disease in the situation is pneumonia. Coxiella burnetii. wind. sheep. soil.

Coxiella burnetii.

If a person could not form C2, which result of complement would be affected? Opsonization Chemotaxis and inflammation Cytolysis, chemotaxis, inflammation, and opsonization Cytolysis

Cytolysis, chemotaxis, inflammation, and opsonization

Which type of cell directly attacks infected cells? Bacterial cells Cytotoxic T-cells Cancerous cells Helper T-cells

Cytotoxic T-cells

HIV directly infects T-cells. Why is this problematic for cell-mediated immunity? HIV causes cytokines to be produced at much higher levels, altering the normal function of the immune system. HIV transforms the T-cells into cancer cells. HIV reprograms these cells to attack the body cells. Cytotoxic T-cells begin to attack the virally infected T-cells, reducing the number of T-cells in the body.

Cytotoxic T-cells begin to attack the virally infected T-cells, reducing the number of T-cells in the body.

Which cells directly attack abnormal cells in the body? Cytotoxic T cells Phagocytes Helper T cells B cells

Cytotoxic cells

If cells are grown in media containing amino acids labeled with radioactive nitrogen (15N), most of radioactivity will be found in the cells DNA. proteins. phospholipids. DNA and proteins. DNA and phospholipids

DNA and protein

Recombinant DNA refers to the synthesis of proteins from genes. DNA resulting when bacterial genes are inserted in an animal genome. study of the function of genes. interaction between human and bacterial cells. study of bacterial ribosomes.

DNA resulting when bacterial genes are inserted in an animal genome.

Which of the following are likely to be found on an MHC-I protein? Damaged mitochondrial fragment Bacterial DNA Bacterial cell wall fragment Membranes from a neighboring dead host cell Bacterial flagella

Damaged mitochondrial fragment

Which of the following is true concerning a lysogenic viral replication cycle? Once the lysogenic portion of the cycle has begun, virus is never produced again. During lysogeny, the viral genome integrates into the host DNA, becoming a physical part of the chromosome. Lysogenic infections are similar to persistent infections, in that virus is constantly produced. During lysogeny, the viral DNA is present as a circular plasmid.

During lysogeny, the viral genome integrates into the host DNA, becoming a physical part of the chromosome.

Which of the following is an example of the symbiotic relationship known as mutualism? E. coli within the large intestine A tapeworm in the gastrointestinal tract of a human Corynebacterium on the surface of the eye Saprophytic Mycobacterium of the ear

E. coli within the large intestine

Malaria is an infectious disease caused by infection with a protozoan. In certain tropical regions, malaria is constantly present. We would say that malaria is a(n) _________ disease in these regions. pandemic sporadic endemic epidemic

Endemic

Which of the following statements about lysogenic conversion is true? Lysogenic bacteria are always less virulent than nonlysogenic bacteria because the viral infection weakens them. Endotoxin production by bacteria is frequently the result of a lysogenic infection. Exotoxin production by bacteria is frequently the result of a lysogenic infection. Lysogenic conversion is a result of the transfer of plasmids from one bacterium to another.

Exotoxin production by bacteria is frequently the result of a lysogenic infection.

In the last segment of the animation, how many regions of the world experience the pandemic during April of year four? Four Two Six Five

Five

How does cytolysis occur via the complement pathway? Triggering the release of histamine Formation of the MAC in invading cells, killing them Disrupting cell wall of pathogens Stimulation of the inflammatory response

Formation of the MAC in invading cells, killing them

Which of the following statements is true regarding hand washing? Hand washing should be done frequently by healthcare workers. Hand washing should be done before and after patient interaction. Hand washing should be done frequently by patients. Frequent and proper hand washing should be routinely done by patients and by healthcare workers, both prior to and after interaction.

Frequent and proper hand washing should be routinely done by patients and by healthcare workers, both prior to and after interaction.

Which of the following is a DNA strand complementary to CGA ATC AGC? GCU UAG UCG GCT TAG TCG CGA ATC AGC TAG GCT GAT

GCT TAG TCG

Frederick Griffith did experiments on genetic transformation. Which of the following statements about his experiments is accurate? Griffith used only pathogenic bacteria in his experiments. The combination of living nonencapsulated bacteria and heat-killed encapsulated bacteria did not cause disease. Griffith used bacteria in which the nonpathogenic strain was encapsulated but the pathogenic strain was not. Griffith found that DNA released from dead (virulent) bacteria entered live (avirulent) bacteria and changed them genetically, causing them to become virulent.

Griffith found that DNA released from dead (virulent) bacteria entered live (avirulent) bacteria and changed them genetically, causing them to become virulent.

Immune cells that secrete cytokines and activate other immune cells are: Cytotoxic T-cells Abnormal body cells Invading pathogenic bacteria Helper T-cells Virally infected cells

Helper T-cells

How do helper T-cells and cytotoxic T-cells work together? Helper T-cells produce cytotoxic T-cells. Cytotoxic T-cells produce cytokines to activate helper T-cells. Cytotoxic T-cells attack abnormal body cells, while helper T-cells attack virally infected cells. Helper T-cells produce cytokines to activate other cells of the immune system.

Helper T-cells produce cytokines to activate other cells of the immune system

The most abundant class of antibodies in serum is IgG. IgM. IgA. IgD. IgE.

IgG

If a patient has been exposed to an antigen for the first time, which class of immunoglobulin appears first? IgD IgG IgE IgM

IgM

Why is vasodilation important to tissue repair? It allows for an increase in oxygen to the site of damage. It allows more nutrients to be delivered to the site of damage. It allows more phagocytes to travel to the site of damage. It allows for an increased delivery of oxygen, nutrients, and phagocytes to the site of damage.

It allows for an increased delivery of oxygen, nutrients, and phagocytes to the site of damage.

How does the protozoan Trypanosoma evade detection by the immune system? It prevents phagosome-lysosome fusion. It can change the surface antigens frequently, preventing the immune system from tracking it. It can resist oxidation inside macrophages. It produces a capsule which is composed of polysaccharides similar to those found in the host.

It can change the surface antigens frequently, preventing the immune system from tracking it.

Why is a release of endotoxin into the bloodstream potentially deadly? It causes necrosis of the liver. It results in dehydration of the patient. It can lower blood pressure and cause the patient to go into shock. Endotoxin can quickly enter the brain from the bloodstream, causing brain damage.

It can lower blood pressure and cause the patient to go into shock.

Trichomonas vaginalis can be distinguished from other parasitic protozoa by which of the characteristics listed below? It has an undulating membrane, infects the vagina, and is frequently transmitted by sexual contact. It is a photosynthetic organism that lives in fresh water. It infects Anopheles mosquitoes and can be transmitted by a bite. It is usually found in drinking water and is associated with fecal contamination.

It has an undulating membrane, infects the vagina, and is frequently transmitted by sexual contact.

Which of the following statements about recombinant DNA technology is FALSE? It has limited application because genes of interest cannot be moved from one type of cell to another. It can be used to screen individuals for many different types of genetic diseases. It allows researchers to make protein products of a gene. It allows researchers to make many copies of a gene of interest.

It has limited application because genes of interest cannot be moved from one type of cell to another.

Which of the following is an advantage of using E. coli to make a human gene product? Endotoxin may be in the product. It does not secrete most proteins. Its genes are well known. It cannot process introns. None of the answers is correct.

Its genes are well known.

Which of the following statements about fungi is true? Fungi are usually identified using biochemical tests. Most fungi reproduce only asexually. Karyogamy refers to a part of the sexual reproduction cycle in which two haploid nuclei fuse to form a diploid zygote. Conidiospores are spores that are enclosed in a specialized sac-like structure.

Karyogamy refers to a part of the sexual reproduction cycle in which two haploid nuclei fuse to form a diploid zygote.

________________ is/are always present in an individual's blood. However, in the absence of infection, it is in an inactive form. Histamine Prostaglandins Cytokines Kinins

Kinins

Which of the following statements regarding latent viral infections is true? Latent viral infections are almost always fatal. During latent infections, small amounts of virus are produced, and virus numbers build up over time. Latent infections can persist for years in an individual without causing any symptoms. Latent viral infections are caused by the slow conversion of cellular glycoproteins from normal to infectious form.

Latent infections can persist for years in an individual without causing any symptoms.

Which of the following statements regarding lichens is FALSE? Lichens are often the first life form to colonize rock or soil. Lichens are very tolerant to pollution. The fungal partner provides a means of attachment and protects the algal partner from desiccation. The algal partner produces carbohydrates that are absorbed by the fungal partner. Lichens represent a mutualistic relationship between a fungus and an alga.

Lichens are very tolerant to pollution.

Endotoxins are also known as interleukin-1. prostaglandins. Lipid A. cytokines.

Lipid A.

The use of phenol (carbolic acid) as a wound disinfectant was first practiced by Holmes. Semmelweis. Lister. Pasteur. Koch.

Lister

Which statement regarding the lymphatic system is true? Lymph nodes are sites of activation of neutrophils, which destroy microbes. The thymus serves as the site for activation of B cells. Lymphatic capillaries possess one-way valves. These valves permit the uptake of fluid from the body but do not allow the fluid to flow back out of the capillaries into the intracellular spaces. The pancreas contains lymphocytes and macrophages that monitor the blood for microbes.

Lymphatic capillaries possess one-way valves. These valves permit the uptake of fluid from the body but do not allow the fluid to flow back out of the capillaries into the intracellular spaces

A urease test is used to identify Myobacterium tuberculosis because urease is a sign of tuberculosis. M. bovis can cause tuberculosis. urea accumulates during tuberculosis. some bacteria reduce nitrate ion. M. tuberculosis produces urease.

M. tuberculosis produces urease.

Further characterization of the S. aureus isolated from George's wound reveals that the strain is MRSA. Why is George's doctor concerned that MRSA has been identified as the causative agent of George's infection? The available treatment options are quite aggressive, including removal of damaged tissue in an effort to contain the infection. MRSA is not typically associated with the type of infection that George has. MRSA is transmissible. There are no effective antibiotic options for treating MRSA.

MRSA is transmissible.

What are leukocidins? Molecules that are capable of destroying phagocytes Molecules that can degrade IgA Molecules that destroy the complement proteins

Molecules that are capable of destroying phagocytes

Which of the following statements about adherence is true? The host cell receptors for bacterial adhesins are usually proteins. Most bacterial adhesins are glycoproteins or lipoproteins. Most bacteria can adhere to any cell in the host. Adhesins are always located on the bacterium's cell membrane.

Most bacterial adhesins are glycoproteins or lipoproteins.

According to your Concept Map, which of the following organisms exhibits antigenic variation? Mycobacterium tuberculosis S. pneumoniae N. gonorrheae H. influenzae

N. gonorrheae

Which compound is being reduced in the reaction shown in the figure? α-ketoglutaric acid and NAD+ NADH and isocitric acid NADH isocitric acid and α-ketoglutaric acid NAD+

NAD+

Meningitis and gonorrhea are caused by Pseudomonas species. Neisseria species. measles virus.

Neisseria species.

A patient who has been hospitalized with uncontrolled muscle spasms has probably been infected with bacteria that secrete a(n) neurotoxin. enterotoxin. superantigen. membrane disrupting toxin.

Neurotoxin

Why would a body cell that is not a phagocyte need to present antigens? Antigens are infectious and can spread to normal cells. Antigens are required for cell-to-cell attachment. Non-phagocytic body cells can become infected with a virus. All cells of the body can engulf invading cells.

Non-phagocytic body cells can become infected with a virus.

Which of the following is NOT a predisposing factor of disease? lifestyle None of the answers are correct; all of these are predisposing factors of disease. genetic background climate occupation

None of the answers are correct; all of these are predisposing factors of disease.

Which one of the following is NOT a zoonosis? Hantavirus pulmonary syndrome cat-scratch disease tapeworm rabies None of the answers is correct; all of these are zoonoses.

None of the answers is correct; all of these are zoonoses.

Which of the following statements concerning prion diseases is true? Prion diseases affect humans but not other animals. Prion diseases are always inherited. Normal host cellular prion proteins (PrPC) are converted into scrapie proteins (PrPSc). Prion diseases affect brain function but do not affect the morphology (overall appearance) of brain tissues.

Normal host cellular prion proteins (PrPC) are converted into scrapie proteins (PrPSc).

Assume you are working for a chemical company and are responsible for growing a yeast culture that produces ethanol. The yeasts are growing well on the maltose medium but are not producing alcohol. What is the most likely explanation? The temperature is too low. O2 is in the medium. Not enough protein is provided. The maltose is toxic. The temperature is too high.

O2 is in the medium.

Which of the following is NOT associated with viruses? capsid envelope organelles nucleic acid spikes

ORGANELLES

Which statement regarding endotoxins is true? Endotoxins induce host cells to produce effective antitoxins that help to protect them against the toxin's effects. One consequence of endotoxins is the activation of blood-clotting proteins. The effects of endotoxins vary greatly, depending on the specific bacterium the produces them. Endotoxins are part of the outer portion of the cell wall of gram-positive bacteria.

One consequence of endotoxins is the activation of blood-clotting proteins.

If a person lacked the ability to form C5, what direct result of complement could still occur? Cytolysis Opsonization Chemotaxis

Opsonization

A population of cells carrying a desired plasmid is called a library. vector. PCR. Southern blot. clone.

PCR

According to the animation, antibodies interact with which innate defenses? Phagocytosis First-line defenses Phagocytosis and the complement system Inflammation The complement system Phagocytosis, inflammation, and the complement system

Phagocytosis and the complement system

Which structure do antigen presenting cells utilize to directly help them present bacterial antigens? Mitochondria Nucleus Phagolysosome Golgi apparatus

Phagolysosome

How can health care workers reduce the occurrence of nosocomial infections? Reduce the number of times they visit a patient Practice more stringent aseptic techniques Administer all medications orally instead of through injections Limit the number of visitors who can see the patient

Practice more stringent aseptic techniques

Who is credited with first observing cells? Robert Hooke Louis Pasteur Anton van Leeuwenhoek Robert Koch Carolus Linnaeus

Robert Hooke

In mice, the LD50 for staphylococcal enterotoxin is 1350 ng/kg, and the LD50 for Shiga toxin is 250 ng/kg. Which of the following statements is true? Shiga toxin is more lethal than staphylococcal enterotoxin. More organisms of Staphylococcal bacteria must be ingested to cause infection, as compared Shigella bacteria. The parenteral route is the preferred portal entry for Shigella bacteria. Staphylococcal enterotoxin is the more lethal of the two toxins.

Shiga toxin is more lethal than staphylococcal enterotoxin.

In mice, the LD50 for staphylococcal enterotoxin is 1350 ng/kg, and the LD50 for Shiga toxin is 250 ng/kg. Which of the following statements is true? The parenteral route is the preferred portal entry for Shigella bacteria. More organisms of Staphylococcal bacteria must be ingested to cause infection, as compared Shigella bacteria. Staphylococcal enterotoxin is the more lethal of the two toxins. Shiga toxin is more lethal than staphylococcal enterotoxin.

Shiga toxin is more lethal than staphylococcal enterotoxin.

Which of the following is classified as a latent disease? tuberculosis infectious mononucleosis shingles influenza

Shingles

Which of the following characteristics of a catheter should be considered, to help minimize the spread of nosocomial infections? Long Washable Inexpensive Single-use Reusable

Single-use

Which statement concerning viral structure is true? All viruses contain an envelope, which is made of lipid, carbohydrate, and protein. Spikes are found on some viruses. They are very consistent in structure and can be used for identification. Animal viruses usually contain a tail sheath and spikes. The proteins in the envelope are capsomeres.

Spikes are found on some viruses. They are very consistent in structure and can be used for identification

How do spirochetes and spirilla differ? Spirochetes and spirilla are basically the same organisms and the terms can be used interchangeably. Spirilla are found in chains of cells whereas spirochetes exist as individual cells. Spirilla have an external flagella but spirochetes have axial filaments. Spirochetes have a rigid, corkscrew shape while spirilla are helical and more flexible. Spirochetes do not have a cell wall but spirilla do.

Spirilla have an external flagella but spirochetes have axial filaments.

Which of the following bacteria are responsible for more infections and more different kinds of infections? Streptococcus Pseudomonas Staphylococcus Neisseria Salmonella

Streptococcus

n 1861, Pasteur conducted his now-famous experiments using flasks with long necks bent into an S-shape. Imagine that you are a scientist working in Pasteur's lab at this time. You decide to tip the flasks so that broth enters the long S-shaped neck. You then return the flask to its upright position. Predict the most likely outcome of tipping one of Pasteur's S-necked flasks. Since the broth had been heated (effectively sterilizing it), no microbes would grow in the broth. Microbes would grow in the broth because the tipping would introduce the oxygen necessary for microbial growth. The broth would remain uncontaminated because no microbes could enter the long S-shaped neck of the flask. The broth would become contaminated with microbes because they were trapped in the neck.

The broth would become contaminated with microbes because they were trapped in the neck.

In the sixth segment of the animation, why is the disease epidemic in North America? The disease occurs at a higher rate than what would normally be expected in this region. The disease occurs at a lower rate than what would normally be expected in this region. The disease has spread to North America from Europe. Only a few cases are occurring in this region.

The disease occurs at a higher rate than what would normally be expected in this region.

Which of the following does NOT contribute to the emergence of infectious diseases? Antibiotic resistance Climatic changes New strains of previously known agents Ease of travel The emergence of infectious diseases can be attributed to all of these

The emergence of infectious diseases can be attributed to all of these

Which of the following statements concerning immunological memory is true? The memory response is usually faster but not as strong. Antibodies produced in response to a secondary infection are mostly IgM. The memory response is due to production of long-lived cells that can respond very rapidly upon second exposure. The memory response involves only B cells.

The memory response is due to production of long-lived cells that can respond very rapidly upon second exposure.

Koch's postulates established criteria for proving that a specific organism causes a specific disease. Which of the following is NOT one of the criteria given by Koch's postulates? The same pathogen must be present in every case of the disease. The pathogen must be isolated from the diseased host and grown in pure culture. The pathogen must be isolated from inoculated animals and must be different from the original organism. The pathogen isolated from a pure culture must cause the disease in a healthy lab animal.

The pathogen must be isolated from inoculated animals and must be different from the original organism.

Which of the following statements about the development of infectious diseases is correct? The period of decline is the time when the infected individual's health rapidly deteriorates. During the incubation period, the infected individual exhibits obvious signs of sickness. The prodromal period is characterized by very severe symptoms. The period of convalescence is the time during which the person regains health and fully recovers (back to the pre-disease state).

The period of convalescence is the time during which the person regains health and fully recovers (back to the pre-disease state).

Which is an example of vehicle disease transmission? The bite of a mosquito containing malaria The transmission of MRSA from skin to skin contact Touching a telephone with cold viruses on its surface The presence of Listeria on undercooked chicken served for dinner

The presence of Listeria on undercooked chicken served for dinner

One of the first set of experiments to refute spontaneous generation was done in 1688 by Francesco Redi. Which of the following statements regarding Francesco Redi's experiments is true? He determined that material from an infectious agent taken from one person could be used to stimulate immunity in another person. His experiments demonstrated that oxygen is essential to all life. His experiments determined a series of conditions that must be satisfied in determining the causative agent of disease. The results of his experiment demonstrated that living organisms are derived from other living organisms.

The results of his experiment demonstrated that living organisms are derived from other living organisms.

Consider a helminthic infection in which an individual is colonized by a parasitic worm. The worm is too big to be engulfed by a phagocytic cell. How does the immune system respond? Numerous phagocytes work cooperatively to ingest the worm. The worm gets coated with antibodies, which activate other cells in the immune system to secrete chemicals that kill it. Antibodies bind to the worm and disrupt its plasma membrane. Blood flow is reduced to the area, which starves the worm of nutrients.

The worm gets coated with antibodies, which activate other cells in the immune system to secrete chemicals that kill it.

Protozoan and helminthic diseases are difficult to treat because they have more genes than bacteria. they replicate inside human cells. they do not reproduce. they do not have ribosomes. their cells are structurally and functionally similar to human cells.

Their cells are structurally and functionally similar to human cells.

Why are invasive procedures likely to increase the risk of nosocomial infections? Invasive procedures must use antibiotics. Invasive procedures require long term hospital stays, thereby increasing the number of visitors seen by the patient. These procedures allow microbes from the skin to enter the bloodstream of the patient. These procedures are carried out by health care workers, who carry resistant microbes.

These procedures allow microbes from the skin to enter the bloodstream of the patient.

Which of the following are functions of lectins? They produce antibodies. They attach to carbohydrates on some bacterial and viral surfaces. They act as opsonins for phagocytosis, they attach to carbohydrates on some bacterial and viral surfaces, and they activate C2 and C4. They produce factor P (properdin). They act as opsonins for phagocytosis. They can activate C2 and C4.

They act as opsonins for phagocytosis, they attach to carbohydrates on some bacterial and viral surfaces, and they activate C2 and C4.

What direct effect do histamines and leukotrienes have on capillaries? They prevent phagocytes from sticking to the walls of capillaries. They decrease the diameter of capillaries. They allow capillary walls to open and become leaky.

They allow capillary walls to open and become leaky.

Which of the following is NOT a property of useful vectors? They must be able to self-replicate. They must have properties that allow their survival in the host cell. They always contain only one gene. They must be small enough to allow them to be manipulated prior to injection

They always contain only one gene.

How are immune cells able to detect foreign pathogens? They are able to detect structures on the surfaces of foreign cells that are not found in the host. They detect foreign, unfamiliar chemical substances released by the invading cells. They can compare the DNA sequences from the foreign cells to host DNA.

They are able to detect structures on the surfaces of foreign cells that are not found in the host.

What do hyaluronidase and kinase have in common? They are both enzymes involved in evading host defense. They both break down components of the extracellular matrix. They both directly prevent phagocytosis. They are both critical components of microbial capsules. All of the above are correct.

They are both enzymes involved in evading host defense.

Which statement best describes restriction enzymes? They are important for cloning applications because they can be used to cut DNA at specific nucleotide sequences. They randomly cut DNA molecules to generate numerous fragments. They can cut only circular plasmid DNA. They are necessary for the polymerase chain reaction (PCR) to occur.

They are important for cloning applications because they can be used to cut DNA at specific nucleotide sequences.

Which of the following statements concerning antigen-presenting cells is true? They are a type of T cell. They transport antigens to the liver, where they can be degraded. They are involved in activating T cells. They are found only in lymphoid tissues.

They are involved in activating T cells

Which of the following statements concerning antigen-presenting cells is true? They are found only in lymphoid tissues. They are involved in activating T cells. They transport antigens to the liver, where they can be degraded. They are a type of T cell.

They are involved in activating T cells.

How do superantigens enable pathogens to hide from the immune system if they actually stimulate the immune system? They cause the immune system to produce an exaggerated response, distracting it from the actual pathogen. They cause the immune system to destroy IgA antibodies. They cause fever, which destroys the complement proteins. They cause the immune system to turn on itself.

They cause the immune system to produce an exaggerated response, distracting it from the actual pathogen.

How can surgeons help to limit nosocomial infections? They should prescribe as many antibiotics as possible. They should prescribe immunosuppressive drugs to their patients. They should perform surgeries and invasive procedures only when absolutely necessary. They should only operate on healthy individuals.

They should perform surgeries and invasive procedures only when absolutely necessary.

What is the role of epidemiology? To learn what diseases can be caused by respiratory pathogens. To learn which organisms cause disease. To learn how to treat and prevent various diseases. To learn which medicines are effective at killing pathogen

To learn how to treat and prevent various diseases.

Tom has a genetic disorder in which he does not synthesize class I MHC proteins or functional NK cells. Which of the following statements would be true for Tom? Tom would be more susceptible to bacterial infections. Tom would not be able to produce antibodies against viruses. Tom would be less susceptible to helminth infections. Tom would not be able to destroy virally-infected cells.

Tom would not be able to destroy virally-infected cells.

Which of the following microorganisms actually grows inside the macrophage? Shigella Streptococcus pneumoniae Tuberculosis bacterium Leishmania Legionella

Tuberculosis bacterium

Which of the following toxins does NOT match the description? hemolysins: membrane-disrupting toxins that destroy erythrocytes Vibrio enterotoxin: a superantigen that destroys epithelial cells tetanus toxin: an A-B neurotoxin that causes uncontrollable muscle contractions streptococcal erythrogenic toxin: a superantigen that damages capillaries and results in a characteristic rash

Vibrio enterotoxin: a superantigen that destroys epithelial cells

How do all viruses differ from bacteria? Viruses are not composed of cells. Viruses do not have any nucleic acid. Viruses are filterable. Viruses do not reproduce. Viruses are obligate intracellular parasites.

Viruses are not composed of cells.

Why is it more difficult to treat viral infections than it is to treat bacterial infections? Viruses have cell walls. Viruses are smaller than human cells. Viruses are very similar to human cells. Viruses use the host cell's processes to carry out their own reproduction.

Viruses use the host cell's processes to carry out their own reproduction.

As a health care worker, I am keenly aware of how important it is to avoid harming my patients. I worry about inadvertently transmitting an infectious disease to an already compromised individual. According to the CDC, what is the MOST important thing I can do to avoid this? Shave my head. Wear shoe covers. Wash my hands before interacting with any patient. Wear a lab coat.

Wash my hands before interacting with any patient.

When would endotoxins be released from a bacterial cell? When the cell attaches to a host cell in the human body When the cell moves toward a energy source When the cell dies During bacterial conjugation

When the cell dies

Pathology refers to the study of structural and functional changes that occur in the body as a result of a disease.

Which of the following statements concerning pathology, infection, and disease is true? The term infection is synonymous with the term disease. The majority of microorganisms are pathogenic. Microorganisms that make up the normal microbiota of an individual never cause disease. Pathology refers to the study of structural and functional changes that occur in the body as a result of a disease.

In the figure, which areas represent antigen-binding sites? a and b a and c b and c c and d b and d

a and b

Which of the following is the best definition of antigen? a pathogen something foreign in the body a chemical that combines with antibodies a chemical that elicits an antibody response and can combine with these antibodies a protein that combines with antibodies

a chemical that elicits an antibody response and can combine with these antibodies

Which of the following is a fomite? pus water insects a hypodermic needle droplets from a sneeze

a hypodermic needle

In the figure, the structure labeled (1) is a plasma membrane. ATP synthase. cytoplasm. NAD+. a cell wall.

a plasma membrane

A gene is best defined as a sequence of nucleotides in DNA that codes for a functional product. a segment of DNA. a sequence of nucleotides in RNA that codes for a functional product. three nucleotides that code for an amino acid. a transcribed unit of DNA.

a sequence of nucleotides in DNA that codes for a functional product.

In the figure, which diagram of a cell wall is resistant to many antibiotics (e.g., penicillin)? a(tubes) b(layers) both a and b neither a nor b The answer cannot be determined.

a(tubes)

A nosocomial infection is only a result of surgery. acquired during the course of hospitalization. always present, but is inapparent at the time of hospitalization. always caused by pathogenic bacteria. always caused by medical personnel.

acquired during the course of hospitalization.

Which of the following form conidiospores? rickettsias spiral and curved bacteria anaerobic gram-negative cocci endospore-forming gram-positive rods and cocci actinomycetes and related organisms

actinomycetes and related organisms

By which of the following mechanisms can a cell transport a substance from a lower to a higher concentration? extracellular enzymes simple diffusion aquaporins active transport facilitated diffusion

active transport

A definitive host harbors which stage of a parasite? larva cyst adult miracidium All of the answers are correct.

adult

Phagocytosis is a process for engulfing large particles (>1μm). Which feature of antibodies will help to make particles larger, therefore enhancing phagocytosis? neutralization agglutination opsonization complement activation

agglutination

Which of the following virulence factors could directly prevent phagocytosis and/or phagocytic degradation? capsules M proteins waxy lipids all of the above none of the above

all the above

Which of the complement pathways employs properdin? Classical pathway Alternative pathway Lectin pathway Alternative and lectin pathways all employ properdin. Classical, alternative, and lectin pathways all employ properdin. The classical and alternative pathways both require properdin.

alternative pathway

Which of the following terms refers to pathways that can function both in anabolism and catabolism? amphibolic pathways homolactic fermentation pathways chemiosmotic pathways light-dependent pathways

amphibolic pathways

The ability of some microbes, such as Trypanosoma or Giardia to alter their surface molecules and evade destruction by the hosts antibodies is called lysogenic conversion. cytopathic effect. cytocidal effect. virulence. antigenic variation.

antigenic variation

Which of the following are best described as short chains of amino acids that are very stable and can have a variety of different antimicrobial activities, such as forming pores in bacterial plasma membranes and inhibiting cell wall synthesis? antimicrobial peptides siderophores mannose-binding lectin antiviral proteins

antimicrobial peptides

Prior to drawing blood for a blood donation, the nurse will scrub the arm with a Betadine solution. This form of antimicrobial control would be called __________. disinfection sterilization antisepsis sanitization

antisepsis

Symptoms of disease differ from signs of disease in that symptoms are specific for a particular disease. always occur as part of a syndrome. are changes observed by the physician. are changes felt by the patient. None of the answers is correct.

are changes felt by the patient.

What type of immunity results from vaccination? innate immunity naturally acquired active immunity naturally acquired passive immunity artificially acquired active immunity artificially acquired passive immunity

artificially acquired active immunity

Transformation is the transfer of DNA from a donor to a recipient cell by a bacteriophage. by crossing over. as naked DNA in solution. by cell-to-cell contact. by sexual reproduction.

as naked DNA in solution

In the figure, which tube shows the expected growth pattern for a facultative anaerobe? a b c d e

b

Most bacteria reproduce by aerial hyphae. fragmentation. budding. binary fission. mitosis.

binary fission

Patients with indwelling catheters are susceptible to infections because bacteria cause infections. their immune systems are weakened. injected solutions are contaminated. biofilms develop on catheters. infections can be transmitted from other people.

biofilms develop on catheters.

The figure shows a typical bacterial growth curve with the x-axis indicating the time (hrs) in culture, and the the y-axis indicating the log of the number of bacteria. In the figure, which section (or sections) shows a growth phase where the number of cells dying equals the number of cells dividing? a b c d a and c

c

In the figure, which areas are similar for all IgG antibodies? a and b a and c b and c c and d b and d

c and d

Which structure acts like an invisibility cloak and protects bacteria from being phagocytized? capsule cell wall cell membrane fimbriae slime layer

capsule

Which enzyme catalyzes the reaction: 2H2O2 → 2H2O + O2? oxidase superoxide dismutase catalase peroxidase

catalase

Lysozyme and the antibiotic penicillin have similar mechanisms of action in that they both cause damage to the bacterial capsule. cell membrane. ribosomes. DNA. cell wall.

cell wall

Which of the following pairs is mismatched? mitochondria - atp production endoplasmic reticulum - internal transport Golgi complex - secretion lysosome - digestive enzymes centrosome - food storage

centrosome - food storage

Thiobacillus oxidizes inorganic sulfur compounds and reduces CO2. This bacterium is a photoheterotroph. gammaproteobacteria. chemoheterotroph. photoautotroph. chemoautotroph.

chemoautotroph.

Which of the following pairs is mismatched? chemoautotrophic bacteria - fix atmospheric nitrogen actinomycetes - reproduce by fragmentation archaea - extremophiles dissimilatory sulfate-reducing bacteria - produce H2S Cytophaga - a gliding, nonfruiting bacterium

chemoautotrophic bacteria - fix atmospheric nitrogen

Which disease would be potentially propagated in an environment without functional plumbing and in which drinking water is contaminated with sewage? ringworm influenza cholera yellow fever

cholera

In bacteria, photosynthetic pigments are found in mesosomes. cytoplasm. ribosomes. chloroplasts. chromatophores.

chromatophores.

Protozoan motility structures include pseudopods. cilia. flagella. cilia and pseudopods only. cilia, flagella, and pseudopods.

cilia, flagella, and pseudopods.

A culture medium consisting of agar, peptone, and beef heart is a chemically defined medium. differential medium. selective medium. complex medium. reducing medium.

complex medium

In the figure, line c points to the microscope's condenser. objective lens. ocular lens. illuminator.

condenser.

A gram-positive bacteria suddenly acquires resistance to the antibiotic methicillin. This trait most likely occurred due to conjugation. transformation. meisosis. binary fission. transduction.

conjugation.

When aerosols containing pathogens spread disease from a distance of less than one meter, it is considered contact transmission. vector transmission. waterborne transmission. airborne transmission.

contact transmission.

The life cycle of the fish tapeworm is similar to that of the beef tapeworm. Which of the following is the most effective preventive measure? not swimming in fish-infested waters salting fish before eating wearing gloves while handling fish refrigerating stored fish cooking fish before eating

cooking fish before eating

The damage caused by ultraviolet radiation is repaired by DNA replication. repaired during translation. never repaired. cut out and replaced. repaired during transcription

cut out and replaced.

An exotoxin that has the ability to kill or damage host cells is referred to as a(n) A-B toxin. enterotoxin. neurotoxin. cytotoxin. superantigen.

cytotoxin

Pus is comprised of dead phagocytes. unused histamines and leukotrienes. collected cells from damaged tissue. excess fluid from leaky blood vessels

dead phagocytes

In which of the following situations would Kochs postulates be utilized? determination of the cause of a patients illness in a hospital microbiology lab determination of the cause of cancer in a patient development of a new antibiotic in a pharmaceutical lab formulation of a vaccine against a new pathogen in a genetic engineering lab whenever the scientific method is used to investigate a microbiological problem

determination of the cause of a patients illness in a hospital microbiology lab

Biogenesis refers to the development of aseptic technique. spontaneous generation of organisms from nonliving matter. development of life forms from preexisting life forms. germ theory of disease.

development of life forms from preexisting life forms.

In macrophages and dendritic cells (so-called antigen-presenting cells) some small parts of the phagocytosed particle are presented to other cells of the immune system. If you were to draw an arrow leading to "antigen presentation" as described above, from which word would it extend? adherence digestion ingestion exocytosis

digestion

You note that the body temperature of one of your patients is starting to increase. As a result, you can infer that all of the following may be occurring in this patient EXCEPT __________. constriction of blood vessels increased metabolic rate shivering dilation of blood vessels

dilation of blood vessels

The use of an antibiotic-resistance gene on a plasmid used in genetic engineering makes replica plating possible. direct selection possible. the recombinant cell unable to survive. the recombinant cell dangerous. All of the answers are correct.

direct selection possible

In the figure, where is ATP produced? a b c d e

e

In the figure, which tube shows the expected growth pattern for a microaerophile? a b c d e

e

Which microscope achieves the highest magnification and greatest resolution? darkfield microscope compound light microscope electron microscope fluorescence microscope phase-contrast microscope

electron microscope

Foreign DNA can be inserted into cells using a variety of different methods. Which method involves the formation of microscopic pores in the cell's membrane? electroporation protoplast fusion heat shock transformation

electroporation

The following choices list several types of diseases, along with factors that may contribute to their emergence. Which disease and associated factor do NOT match? spread of cholera to new regions: modern travel emergence of avian influenza A (H5N1): use of antibiotics increased incidence of malaria: global warming Increased incidence of Lyme disease: increases in deer populations

emergence of avian influenza A (H5N1): use of antibiotics

If a disease occurs at a fairly stable rate, it is said to be pandemic. endemic. epidemic. sporadic.

endemic

Malaria is an infectious disease caused by infection with a protozoan. In certain tropical regions, malaria is constantly present. We would say that malaria is a(n) _________ disease in these regions. epidemic pandemic endemic sporadic

endemic

If one is examining a blood smear from a patient with a parasitic worm infection, which of the following leukocytes would be found in increased numbers (as opposed to a blood smear from a normal patient NOT infected with worms)? basophils eosinophils monocytes lymphocytes

eosinophils

If one is examining a blood smear from a patient with a parasitic worm infection, which of the following leukocytes would be found in increased numbers (as opposed to a blood smear from a normal patient NOT infected with worms)? lymphocytes eosinophils monocytes basophils

eosinophils

The graph in the figure shows the incidence of polio in the United States. The period between 1945 and 1955 indicates a(n) sporadic infection. endemic level. epidemic level. pandemic. communicable disease.

epidemic level.

Which of the following are found primarily in the intestines of humans? gram-positive cocci facultatively anaerobic gram-negative rods gram-negative aerobic rods and cocci endospore-forming rods aerobic, helical bacteria

facultatively anaerobic gram-negative rods

Endospores are a reproductive structure. True False

false

PABA serves as the competitive inhibitor in the action of sulfanilamides. True False

false

Pure cultures can easily be obtained on streak plates, even if the desired bacteria are present in very low concentrations. True False

false

The Gram stain is not suitable for identifying members of the Archaea. True False

false

The Platyhelminthes group includes roundworms, tapeworms, and flukes. True False

false

The greater resolution of the electron microscope compared to the compound microscope is due to the longer wavelengths of the electrons used to examine specimens. True False

false

The inflammatory response can only be triggered by an infection. True False

false

The process of pasteurization to reduce food spoilage utilizes high heat to kill all bacteria present. True False

false

The use of enzymes is necessary to increase the activation energy requirements of a chemical reaction. True False

false

When haptens attach to carrier molecules, an epitope forms on hapten which then can be bound to antibody. True False

false

The microbial process of converting sugars to alcohol is known as pasteurization. fermentation. alcoholism. tyndallization. lyophilization.

fermentation

Which of the following would be the first sign of an infection that resulted in the release of endotoxin? Weakness Nausea Pain Fever

fever

Which type of bacterial enzyme helps spread Streptococcus pyogenes by digesting blood clots? coagulase fibrinolysin collagenase hyaluronidase

fibrinolysin

Sulfanilamides interfere with __________. protein synthesis in helminths folic acid synthesis in bacteria anaerobic metabolism in protozoa protein synthesis in fungi

folic acid synthesis in bacteria

Deleting or inserting one nucleotide pair in the middle of a gene is an example of which of the following? missense mutation frameshift mutation nonsense mutation base substitution

frameshift mutation

A drug that inhibits mitosis, such as griseofulvin, would be more effective against gram-negative bacteria. wall-less bacteria. fungi. mycobacteria. gram-positive bacteria.

fungi

Helminthic diseases are usually transmitted to humans by respiratory route. vectors. genitourinary route. gastrointestinal route. aerosols.

gastrointestinal route.

Which of the following pairings of recombinant DNA techniques and applications does NOT match? genetic modification of yeast: production of purified insulin gene therapy: replacing a defective gene gene silencing: production of subunit vaccines PCR: making many copies of a segment of DNA

gene silencing: production of subunit vaccines

Antibiotics can lead to septic shock if used to treat viral infections. gram-negative bacterial infections. protozoan infections. gram-positive bacterial infections. helminth infestations.

gram-negative bacterial infections.

You have isolated a motile, gram-positive cell with no visible nucleus. You can safely assume that the cell has a mitochondrion. has 9 pairs + 2 flagella. has a cell wall. lives in an extreme environment. has cilia.

has a cell wall.

According to the animation, B cells interact directly with phagocytes. inflammation. helper T cells. the complement system.

helper T cells

The major food producers for other living organisms is/are higher plants. cyanobacteria. algae. higher plants and algae. higher plants, cyanobacteria, and algae.

higher plants, cyanobacteria, and algae.

Antibodies are a part of which type of immunity? Humoral Cell-mediated Neither humoral nor cell-mediated Both humoral and cell-mediated

humoral

Which part of the adaptive immune response involves B cells? Cell-mediated Both humoral and cell-mediated Humoral Neither humoral nor cell-mediated

humoral

Salts and sugars work to preserve foods by creating a lower osmotic pressure. lower pH. hypotonic environment. depletion of nutrients. hypertonic environment.

hypertonic environment.

One effect of washing regularly with antibacterial agents is the removal of normal microbiota. This can result in fewer diseases. no bacterial growth because washing removes their food source. increased susceptibility to disease. normal microbiota returning immediately. body odor.

increased susceptibility to disease.

In which of the following patterns of disease does the patient experience no signs or symptoms? prodromal decline convalescence incubation incubation and convalescence

incubation and convalescence

A patient acquires an infection by touching a contaminated door handle. Which mode of transmission best describes this scenario? indirect contact transmission direct contact transmission vehicle transmission droplet transmission

indirect contact transmission

Which of the following methods of action would be bacteriostatic? inhibition of cell wall synthesis injury to plasma membrane competitive inhibition with folic acid synthesis competitive inhibition with DNA gyrase inhibition of protein synthesis

inhibition of protein synthesis

Bacteriophage replication differs from animal virus replication because only bacteriophage replication involves replication of viral nucleic acid. lysis of the host cell. adsorption to specific receptors. assembly of viral components. injection of naked nucleic acid into the host cell.

injection of naked nucleic acid into the host cell.

Mucous membranes are a part of cell-mediated immunity. adaptive defense. the complement system. humoral immunity. innate defense.

innate defense

Which of the following is an event that ultimately results in activation of complement C3 by splitting it into C3a and C3b? binding of factors B, D, and P to antibodies on bacteria linkage of C2b with C4a interaction of mannose-binding lectin with mannose molecules on a bacterium binding of C2 to antigen-antibody complexes

interaction of mannose-binding lectin with mannose molecules on a bacterium

What do tapeworms eat? intestinal contents red blood cells host tissues intestinal bacteria plant matter

intestinal contents

Antigen processing and presentation is the way foreign cells engulf macrophages. is only accomplished by bacterial cells. is a way for a cell to give information about its activities. is a way for viruses to infect cells.

is a way for a cell to give information about its activities.

Innate immunity involves T cells and B cells. provides increased susceptibility to disease. involves a memory component. is nonspecific and present at birth. is slower than adaptive immunity in responding to pathogens

is nonspecific and present at birth.

Actinomycetes differ from fungi in that actinomycetes cause disease. are chemoheterotrophs. lack a membrane-bounded nucleus. are decomposers. require light.

lack a membrane-bounded nucleus.

A disease in which the causative agent remains inactive for a time before producing symptoms is referred to as subacute. zoonotic. acute. subclinical. latent.

latent

During which growth phase will gram-positive bacteria be most susceptible to penicillin? lag phase log phase death phase stationary phase The culture is equally susceptible during all phases.

log phase

Macrophages arise from which of the following? lymphocytes monocytes neutrophils eosinophils basophils

lymphocytes

In which intracellular compartment would you expect most of the digestive enzymes involved in pathogen destruction to be found? phagosome macrophage phagocytosis lysosome

lysosome

Which of the following best describes the flow of information in cells? DNA is converted to RNA, which is then converted to protein. DNA acts as a messenger. It binds to a ribosome and provides instructions for making protein. mRNA is made by copying specific regions of DNA called genes. Ribosomes use mRNA as instructions, which provide a code specifying the order of amino acids in a protein. Ribosomes make proteins by randomly linking amino acids together.

mRNA is made by copying specific regions of DNA called genes. Ribosomes use mRNA as instructions, which provide a code specifying the order of amino acids in a protein.

The reaction catalyzed by reverse transcriptase is DNA → DNA. DNA → mRNA. mRNA → cDNA. mRNA → protein. tRNA → mRNA.

mRNA → cDNA.

A commensal bacterium does not receive any benefit from its host. may also be an opportunistic pathogen. is beneficial to its host. does not infect its host. is beneficial to, and does not infect, its host.

may also be an opportunistic pathogen.

Microbes have very narrow optimum temperature ranges. Which of the following classifications of microbes are most likely to cause human disease, based on temperature requirements? mesophiles hyperthermophiles psychrophiles thermophiles

mesophiles

The major significance of Robert Koch's work is that diseases can be transmitted from one animal to another. microorganisms are the result of disease. microorganisms cause disease. microorganisms can be cultured. microorganisms are present in a diseased animal.

microorganisms cause disease.

Which of the following pairs is mismatched? mosquito - encephalitis tick - Rocky Mountain spotted fever mosquito - Pneumocystis tick - Lyme disease mosquito - malaria

mosquito - Pneumocystis

The most frequently used portal of entry for pathogens is the skin. parenteral route. mucous membranes of the gastrointestinal tract. mucous membranes of the respiratory tract. All of these portals are used equally.

mucous membranes of the respiratory tract.

Polio is transmitted by ingestion of water contaminated with feces containing polio virus. What portal of entry does polio virus use? skin only parenteral only mucous membranes only skin and parenteral skin, parenteral, and mucous membranes

mucous membranes only

Each of the following organisms would be considered a microbe EXCEPT virus. yeast. bacterium. protozoan. mushroom.

mushroom

An individual may be exposed to a pathogen and become infected without actually getting sick. This is known as a subclinical infection. Even in subclinical infections, the individual's adaptive immune system can generate memory for the pathogen. What type of adaptive immunity is this? naturally acquired active immunity naturally acquired passive immunity artificially acquired passive immunity artificially acquired active immunity

naturally acquired active immunity

What type of immunity results from recovery from mumps? innate immunity naturally acquired active immunity naturally acquired passive immunity artificially acquired active immunity artificially acquired passive immunity

naturally acquired active immunity

Newborns' immunity due to the transfer of antibodies across the placenta is an example of innate immunity. naturally acquired active immunity. naturally acquired passive immunity. artificially acquired active immunity. artificially acquired passive immunity.

naturally acquired passive immunity.

The flu virus mutates fairly frequently. Its adhesive proteins change such that we have different "strains" of influenza each year. When a particular flu virus mutates such that its adhesive proteins change, which function of antibodies is disrupted? neutralization agglutination complement activation opsonization

neutralization

When an antibody binds to a toxin, the resulting action is referred to as neutralization. agglutination. ADCC. apoptosis. opsonization.

neutralization.

Which of the following is NOT a characteristic inherent of the non-endospore-forming gram-positive rods? carry out fermentative metabolism nonpathogenic are aerotolerant lack cell walls display a branched filamentous morphology

nonpathogenic

Assume you have isolated a multicellular heterotrophic organism that produces coenocytic hyphae, motile zoospores, and cellulose cell walls. It is most likely a(n) ascomycete fungus. oomycote alga. tapeworm. green alga. zygomycete fungus.

oomycote alga.

Antibiotics that target cell wall synthesis ultimately cause bacterial cell death as a result of inhibition of molecular transport. decreased synthesis of peptidoglycan. cell shrinkage. osmotic lysis. plasmolysis.

osmotic lysis.

Endotoxins are part of the gram-negative cell wall. A-B toxins. associated with gram-positive bacteria. excreted from the cell. molecules that bind nerve cells.

part of the gram-negative cell wall.

Consider various effects of moist and dry heat to control microbial growth. Which of the following methods would best reduce microbes without altering the taste and chemical composition of beer? pasteurization boiling hot-air sterilization autoclaving

pasteurization

Which of the following antimicrobial agents has the fewest side effects? chloramphenicol streptomycin penicillin tetracycline erythromycin

penicillin

A child falls and suffers a deep cut on her leg. The cut went through her skin and she is bleeding. Which of the following defense mechanisms will participate in eliminating contaminating microbes? acidic skin secretions mucociliary escalator normal skin flora lysozyme phagocytosis in the inflammatory response

phagocytosis in the inflammatory response

Mycobacterium tuberculosis is an intracellular pathogen of humans. After being ingested by a macrophage, it prevents formation of the ___________ by preventing fusion of the phagosome with the ___________________. lysosome, phagolysosome phagolysosome, lysosome lysosome, opsonins opsonins, lysosome

phagolysosome, lysosome

Which of the following antibiotics is NOT bactericidal? penicillin polyenes aminoglycosides cephalosporins rifampins

polyenes

Borrelia is classified as a spirochete because it possesses an axial filament. is a rod. is a pathogen. is aerobic. is transmitted by ticks.

possesses an axial filament

The use of suicide genes in genetically modified organisms is designed to provide a means to eliminate non-modified organisms. kill the modified organisms before they are released in the environment. provide for resistance of the modified organisms to pesticides. prevent the growth of the modified organisms in the environment. delete genes necessary for modified organisms growth.

prevent the growth of the modified organisms in the environment.

In the figure, the antibiotic chloramphenicol binds the 50S ribosome as shown. From this information you can conclude that chloramphenicol prevents transcription in eukaryotes. prevents translation in prokaryotes. prevents translation in eukaryotes. prevents transcription in prokaryotes. prevents mRNA-ribosome binding

prevents translation in prokaryotes.

More than half of our antibiotics are produced by Fleming. produced by fungi. synthesized in laboratories. produced by bacteria. produced by eukaryotic organisms.

produced by bacteria.

Escherichia coli belongs to the green sulfur bacteria. actinomycetes. gram-positive bacteria. proteobacteria. spirochetes

proteobacteria.

In microscopy, the term resolution refers to the ability to distinguish fine structure and detail in a specimen. is only observed in stained specimens. is improved when longer wavelengths of light are employed. refers to magnification when using the electron microscope. is the same as the total magnification of a specimen.

refers to the ability to distinguish fine structure and detail in a specimen.

Rickettsias differ from chlamydias in that rickettsias form elementary bodies. require an arthropod for transmission. are intracellular parasites. are gram-negative. are enterics.

require an arthropod for transmission.

Which of the following is a fungal zoonosis that can be transmitted by direct contact? ringworm tapeworm Lyme disease West Nile encephalitis

ringworm

Which of the following types of microscopes is best used for observing the surfaces of intact cells and viruses? scanning electron microscope phase-contrast microscope brightfield microscope fluorescence microscope darkfield microscope

scanning electron microscope

A culture medium on which only gram-positive organisms grow and a yellow halo surrounds Staphylococcus aureus colonies is called a(n) selective medium. differential medium. enrichment culture. selective and differential medium. differential and enrichment culture.

selective and differential medium.

Endotoxins in sterile injectable drugs could cause giant cell formation. infection. no damage, because they are sterile. septic shock symptoms. nerve damage.

septic shock symptoms

The health of the patient should be the primary concern of the healthcare worker. is secondary to the health of the healthcare worker. is secondary to the health of co-workers in healthcare settings.

should be the primary concern of the healthcare worker.

Which of the following is the best definition of epitope? specific regions on antigens that interact with haptens specific regions on antigens that interact with antibodies specific regions on antigens that interact with MHC class molecules specific regions on antigens that interact with T-cell receptors specific regions on antigens that interact with perforins

specific regions on antigens that interact with antibodies

All of the following bacteria are motile. Which does NOT have flagella? spirochetes Salmonella Escherichia helical bacteria Pseudomonas

spirochetes

Axial filaments are found on staphylococci. spirochetes. rod-shaped bacilli. streptococci.

spirochetes.

Bacteria that cause periodontal disease have adhesins for receptors on streptococci that colonize on teeth. This indicates that streptococcal colonization is necessary for periodontal disease. bacteria that cause periodontal disease adhere to gums and teeth. streptococci get bacterial infections. bacteria that cause periodontal disease adhere to teeth. streptococci cause periodontal disease.

streptococcal colonization is necessary for periodontal disease.

According to the operon model, for the synthesis of an inducible enzyme to occur, the substrate must bind to the repressor. repressor must bind to the operator. end-product must not be in excess. repressor must not be synthesized. substrate must bind to the enzyme.

substrate must bind to the repressor.

A person who attended a picnic early in the day develops a very high fever and is unresponsive by the evening. This person most likely has been exposed to a(n) superantigen. membrane disrupting toxin. enterotoxin. cytotoxin.

superantigen

Which enzyme catalyzes the reaction: O2- + O2- + 2H+ → H2O2 + O2? peroxidase superoxide dismutase oxidase catalase

superoxide dismutase

Measles viruses are capable of inactivating host defenses by producing leukocidins. destroying complement proteins. producing superantigens. suppressing the immune system.

suppressing the immune system.

The antimicrobial drugs with the broadest spectrum of activity are penicillin G. tetracyclines. macrolides. aminoglycosides. chloramphenicol.

tetracyclines

PCR can be used to identify an unknown bacterium because the RNA primer is specific. DNA polymerase will replicate DNA. DNA can be electrophoresed. all cells have DNA. all cells have RNA.

the RNA primer is specific.

Use of antibiotics in animal feed leads to antibiotic-resistant bacteria because the antibiotics kill susceptible bacteria, but the few that are naturally resistant live and reproduce, and their progeny repopulate the host animal. the antibiotics persist in soil and water. the antibiotics cause new mutations to occur in the surviving bacteria, which results in resistance to antibiotics. bacteria from other animals replace those killed by the antibiotics. the few surviving bacteria that are affected by the antibiotics develop immunity to the antibiotics, which they pass on to their progeny.

the antibiotics kill susceptible bacteria, but the few that are naturally resistant live and reproduce, and their progeny repopulate the host animal.

Which of the complement pathways was discovered first? The classical pathway The lectin pathway The alternative pathway

the classical pathway

Antibodies from cellular immune responses are used in the alternative pathway. the lectin pathway. the classical pathway. both the classical and alternative pathways.

the classical pathway.

Expected prevalence of a disease is the total number of cases of a disease over a period of time. the anticipated geographical spread of a disease based on past observances. the number of new cases of a disease over a period of time. the expected occurrence of a disease based on past observations.

the expected occurrence of a disease based on past observations.

Diapedesis is the increase in the diameter of blood vessels. the production and release of chemicals during inflammation. the attachment of phagocytes to the walls of capillaries. the migration of phagocytes through blood vessels to the site of tissue damage.

the migration of phagocytes through blood vessels to the site of tissue damage.

The yeast Candida albicans does not normally cause disease because of ______. other fungi the transient microbiota the normal microbiota parasitic bacteria

the normal microbiota

Where are phospholipids most likely found in a eukaryotic cell? surrounding flagella ribosomes the plasma membrane around organelles the plasma membrane, around organelles, and surrounding flagella

the plasma membrane, around organelles, and surrounding flagella

Molecular biology is the study of protein synthesis. DNA synthesis. the structure and function of macromolecules essential to life. RNA replication. enzyme function.

the structure and function of macromolecules essential to life.

The specificity of an antibody is due to its valence. the H chains. the L chains. the constant portions of the H and L chains. the variable portions of the H and L chains.

the variable portions of the H and L chains.

Normal microbiota provide protection from infection in each of the following ways EXCEPT they change the pH of the environment. they produce antibacterial chemicals. they make the chemical environment unsuitable for nonresident bacteria. they compete with pathogens for nutrients. they produce lysozyme.

they produce lysozyme.

If a patient notices a healthcare worker not following suggested precautions, they should immediately wash their hands. they should immediately bring it to the attention of the healthcare worker. they should leave the healthcare facility immediately.

they should immediately bring it to the attention of the healthcare worker.

Oxygen crosses a plasma membrane by osmosis. through porins. through simple diffusion. with the help of a nonspecific transporter. through facilitated diffusion.

through simple diffusion.

In which of the following cases would the Limulus amebocyte lysate (LAL) assay be used? to check for enterotoxins to detect the presence of the botulinum toxin to ensure that a sterilized medical device is free of endotoxin to confirm the diagnosis of gas gangrene

to ensure that a sterilized medical device is free of endotoxin

The purpose of a mordant in the Gram stain is to remove the simple stain. to make the flagella visible. to make gram-negative cells visible. to prevent the crystal violet from leaving the cells. to make the bacterial cells larger.

to prevent the crystal violet from leaving the cells

Nonpathogenic Vibrio cholerae can acquire the cholera toxin gene by conjugation. transformation. transduction. phagocytosis. infecting a pathogenic Vibrio cholerae.

transduction

A student has obtained a sample of pond water for study. Using the high-power lens, he observes several cells with nuclei. He can conclude that the cells are NOT bacteria. True False

true

An apoenzyme that loses its coenzyme subunit will be non-functional. True False

true

An isolated colony on a streak plate contains millions or billions of identical cells. True False

true

Aspirin alleviates pain, inflammation, and fever by inhibiting prostaglandins. True False

true

Autoclaving is the most effective method of moist heat sterilization. True False

true

Bacterial growth refers to an increase in the numbers of cells in a bacterial culture. True False

true

Bioinformatics is the use of computer technology to compare and analyze genome sequence. True False

true

Carbon fixation occurs during the light-independent phase of photosynthesis. True False

true

Currently, no members of Archaea have been linked to human disease. True False

true

Dogs do not get measles because their cells lack the correct receptor sites for that virus. True False

true

Ergot and aflatoxin are toxins sometimes found in grains contaminated with fungi. True False

true

Glycolysis is utilized by cells in both respiration and fermentation. True False

true

In a completed Gram stain, gram-positive bacteria are purple. True False

true

In general, ATP is generated in catabolic pathways and expended in anabolic pathways. True False

true

Ingestion of certain lactic acid bacteria (LABs) has been shown to be beneficial for function and health of the intestinal tract. True False

true

Maturation of stem cells into mature blood cells occurs in the red bone marrow. True False

true

Moist heat destroys organisms by denaturing proteins. True False

true

Nitrogen-fixing bacteria, such as cyanobacteria, can use atmospheric nitrogen (N 2 ) for their nitrogen source. True False

true

Once an enzyme has converted substrates into products, the active site reverts back to its original form. True False

true

One of the first commercial successes of recombinant DNA technology was the production of human insulin using genetically engineered E. coli. True False

true

Some antimicrobial chemicals are considered to be disinfectants and antiseptics. True False

true

The implementation of vaccinations occurred prior to experimental support for the germ theory of disease. True False

true

The limit of resolution of the compound microscope illuminated with visible light is approximately 0.2 μm. True False

true

The majority of bacterial species on Earth have not been successfully cultivated. True False

true

Which cytokines are believed to contribute to autoimmune disease, such as rheumatoid arthritis? interferons chemokines hematopoietic cytokines tumor necrosis factor (TNF)

tumor necrosis factor (TNF)

DNA is constructed of a single strand of nucleotides with internal hydrogen bonding. two strands of nucleotides running antiparallel. two strands of identical nucleotides with hydrogen bonds between them. two complementary strands of nucleotides bonded AC and GT. None of the answers is correct.

two strands of nucleotides running antiparallel.

Protein synthesis in eukaryotes is similar to the process in prokaryotes in that both eukaryotes and prokaryotes use methionine as the start amino acid. have introns. have exons. require snRNPS. use codons to determine polypeptide sequences

use codons to determine polypeptide sequences

Development of emerging infectious disease can be a result of all of the following EXCEPT modern transportation. changes in the environment. microbial mutation. overuse of antibiotics. use of genetically modified foods.

use of genetically modified foods.

Biotechnology involves the use of microorganisms to make desired products. use of animal cells to make vaccines. development of disease-resistant crop plants. use of microorganisms to make desired products and the use of animal cells to make vaccines. use of microorganisms to make desired products, the use of animal cells to make vaccines, and the development of disease-resistanct crop plants.

use of microorganisms to make desired products, the use of animal cells to make vaccines, and the development of disease-resistanct crop plants.

All of the following occur during inflammation. What is the first step? phagocyte migration diapedesis repair vasodilation margination

vasodilation

Plague is transmitted through the bite of an infected flea. Which of the following best describes this mode of transmission? direct contact transmission vehicle transmission indirect contact transmission vector transmission

vector transmission

A cold transmitted by a facial tissue is an example of which form of disease transmission? vector indirect contact transmission droplet transmission vehicle transmission

vehicle transmission

A dog develops a diarrheal disease after drinking water from a creek during a hike with his owner. Which of the following best describes this method of disease transmission? vector transmission vehicle transmission contact transmission There is not enough information to determine the mode of transmission.

vehicle transmission

Epidemiology is defined as the study of where and when a disease occurs, and how it is transmitted. where a disease occurs. when a disease occurs. how a disease is transmitted.

where and when a disease occurs, and how it is transmitted.