BIO208-210 _ Final Exam
The electron carrier flavin adenine dinucleotide exists in three forms; FAD, FADH, and FADH2. Which form of the electron carrier is the most oxidized? FAD FADH FADH2
FAD
The figure shows a molecule of DNA being replicated. If base 5 is thymine, what is base 5'? cytosine uracil thymine guanine adenine
adenine
At the start of 2015, 36.5 million people were living with HIV in the world. If 2 million people contract HIV in 2015, what was the incidence of HIV in the world in 2015? (Assume the world population at the end of 2015 was 7.5 billion) 2 million/36.5 billion 38.5 million/7.5 billion 2 million/36.5 million 1 million/36.5 million 2 million/7.5 billion
2 million/7.5 billion
The doubling time of a bacterium was measured at two different temperatures. Which results would be expected of a thermophile? 20 minutes at 42⁰C; 220 minutes at 62⁰C no growth at 10⁰C; 20 minutes at 37⁰C 220 minutes at 42⁰C; 20 minutes at 62⁰C 20 minutes at 10⁰C; 220 minutes at 37⁰C 220 minutes at 10⁰C; 20 minutes at 37⁰C
220 minutes at 42⁰C; 20 minutes at 62⁰C
Scenario 14.1 During a six-month period, 239 cases of pneumonia occurred in a town of 300 people as a result of Coxiella burnettii infections. Before the outbreak, 2000 sheep were kept 30 miles northwest of the town, 95% of sheep tested were positive for C. burnetii. Wind blew from the northwest, and rainfall was 0.5 cm compared with 7 to 10 cm during each of the previous three years. In situation 14.1 what is the incidence of pneumonia in humans for the six-month period? 239/539 = 44% 95% 300 239/300 = 77% 95% of 2000 = 1900
239/300 = 77%
E. coli growth is shown on agar plates incubated at three different temperatures (22⁰C, 30⁰C, and 37⁰C). Based on the amount of growth on each plate, the bacterial enzymes function best at ____⁰C because at other temperatures the enzymes are ____ . 22, denatured 37, less concentrated 37, denatured 30, absent 20, altered
37, denatured
At the start of 2015, 36.5 million people were living with HIV in the world. If 2 million people contract HIV in 2015, what was the prevalence of HIV in the world at the end of 2015? (Assume the world population at the end of 2015 was 7.5 billion) 36.5 million/7.5 billion 1 million/36.5 million 1 million/7.5 billion 38.5 million/7.5 billion 2 million/36.5 billion
38.5 million/7.5 billion
Place the phases of phagocytosis in the correct order: 1 - Ingestion of microbe by phagocyte 2 - Digestion of microbe by enzymes 3 - Discharge of waste materials 4 - Chemotaxis and adherence 5 - Formation of phagolysosome 4,2,1,5,3 4,1,5,2,3 4,1,2,3,5 1,2,3,4,5 5,1,2,3,4
4,1,5,2,3
A strain of Neisseria gonorrheae that was formerly sensitive to penicillin has recently acquired the ability to produce penicillinase, an enzyme that inactivates penicillin. Evidence indicates that this is not a new mutation but rather a gene received from another bacterium. The gene is now spreading rapidly among the population, causing the recipient bacteria to be resistant to penicillin. Place the following steps in the order in which they most likely occurred to result in the production of penicillinase. 1. The penicillinase mRNA was translated into the protein penicillinase. 2. Recombination occurred, placing the penicillinase gene in the Neisseria gonorrheae genome. 3. The penicillinase gene was replicated along with all of the other DNA prior to cell division, resulting in vertical transmission of the gene to daughter cells. 4. Transformation introduced the penicillinase gene to this strain of Neisseria gonorrheae. 5. The penicillinase gene was transcribed into mRNA. 4,5,2,3,1 4,5,3,1,2 4,2,5,1,3 2,1,3,5,4 1,2,3,4,5
4,2,5,1,3
Which of the following would alter a B cell's ability to bind to an antigen? Inhibition of the B cell's ability to present antigen on MHCII. Damage to the B cell's Toll-Like Receptors (TLRs). A reduction in the number of MHCI molecules on the B cell surface. A DNA mutation that causes an alteration in the B cell receptor. Coating the B cell in antibody.
A DNA mutation that causes an alteration in the B cell receptor.
Which of the following forms of metabolism produces the MOST ATP per molecule of glucose? Aerobic respiration Lactic acid fermentation Alcohol fermentation Anaerobic respiration
Aerobic respiration
Which is an example of an opportunistic infection? After taking a course of antibiotics, C. difficile normally found in the gut increases in number. A person catches the flu virus which then allows for the overgrowth of some normal biota and development of bacterial pneumonia. After taking a course of antibiotics, C. difficile normally found in the gut increases in number AND A person catches the flu virus which then allows for the overgrowth of some normal biota and development of bacterial pneumonia. A strain of pathogenic E. coli not normally present in the gut microbiome is ingested in food and causes food poisoning. A person is infected by C. tetani after being cut with a rusty nail.
After taking a course of antibiotics, C. difficile normally found in the gut increases in number AND A person catches the flu virus which then allows for the overgrowth of some normal biota and development of bacterial pneumonia.
Regarding Louis Pasteur's experiments with the S-neck flask, which of the following statements is TRUE? Air exchange was possible between the interior of the flask and the outside air. The possibility of contamination by microbes in the air was removed. All preexisting microorganisms were killed. All of the answers are TRUE. A food source was provided in the broth.
All of the answers are TRUE.
Neisseria gonorrhoeae is the cause of gonorrhea. All of these choices are correct. virulent due to fimbriae and a protease that inactivates IgA. can cause eye infections in babies born of infected mothers. called the gonococcus.
All of these choices are correct.
Keeping in mind how Griffith did his transformation experiments, which of the following types of Strepococcus pneumoniae, when combined into the same syringe, will NOT kill mice? (R refers to rough strain, and S refers to smooth strain) Heat-killed R mixed with live S None of these mixtures will kill mice All of these mixtures will kill mice Live R mixed with live S Live R mixed with heat-killed S
All of these mixtures will kill mice
The influenza vaccine is made by combining the most prevalent strains from the previous flu season. Which event would MOST reduce the effectiveness of the new vaccine? The summer is especially wet which increases the amount of allergens in the environment. An avian (bird) flu combines with a human flu to make a new hybrid flu strain. A single base mutation in the RNA genome of the flu virus spontaneously occurs. The flu virus undergoes and antigenic drift and the Neuraminidase spike is altered.
An avian (bird) flu combines with a human flu to make a new hybrid flu strain.
Why is DNA replication essential for a cell? Because DNA is double-stranded. An organism must copy its DNA to pass genetic information on to its offspring. It allows the organism to repair any mistakes. All organisms require two copies of DNA.
An organism must copy its DNA to pass genetic information on to its offspring.
Acquired specific immunity involves the response of skin barriers. lysozyme. B and T lymphocytes. mucus membranes. interferon.
B and T lymphocytes.
Which of the cells listed below can present exogenous antigens on Class II MHC proteins? Virus-infected epithelial cells Healthy epithelial cells B cells Macrophages B cells or macrophages
B cells or macrophages
Bacteria were discovered in 1676 but viruses were not discovered until 1892. Why were viruses discovered so much later than bacteria? Bacteria are much more plentiful in the environment than viruses. Bacteria are multicellular and viruses are unicellular. Viruses are more motile and therefore difficult to catch in a microscope field of vision. Bacteria are larger than viruses.
Bacteria are larger than viruses.
Which of the following is NOT an example of a symbiotic relationship? S. epidermidis lives on human skin and feeds on sloughed off skin cells. Virus particles invade a host cell in order to replicate. Bacteria require nutrients in order to reproduce by binary fission. E. coli live in the human intestine and obtain nutrients from the host while producing vitamins used by the host.
Bacteria require nutrients in order to reproduce by binary fission.
Burt is attempting to recreate Pasteur's famous experiment disproving Spontaneous Generation. He adds broth to a flask, heats the neck to bend it into an S-shape, and then heats the broth. After several days, Burt observes that the broth is cloudy and there is microbe growth. Which of the following could have led to this result? Burt used chicken broth in the flask instead of beef broth used by Pasteur. After the flask had cooled, Burt handled it with his bare hands and set it on a countertop that was not sterilized. A laboratory down the hall studies a motile bacteria that possess several flagella that propel the cells. Burt did not bring the broth to a full boil but left it at low heat for a long period of time. When heating the flask, the steam was allowed to escape through the open end of the S-shaped neck.
Burt did not bring the broth to a full boil but left it at low heat for a long period of time.
Which of the following is incorrect about temperate phages? Cause viral DNA to be incorporated into the bacterial chromosome Cause lysis of host cells Viral DNA is replicated with host DNA and passed on to host cell progeny Phage DNA is present in the host cell when the virus is in lysogeny Viral DNA enters host cell and becomes latent as a prophage
Cause lysis of host cells
What process generates many B cells that are activated against specific antigens? Opsonization Clonal selection Antibody production Antigen expression Antigen presentation
Clonal selection
If you performed a Gram stain and forgot to add the iodine, what would be the likely outcome? The results would be opposite; Gram negative cells would stain purple and Gram positive cells would stain pink. Crystal violet and safranin would both get stuck in the Gram positive and Gram negative cell walls and all cells would stain brown. The results would not be changed; Gram negative cells would stain pink, Gram positive cells would stain purple. Crystal violet would wash out of both cell types and safranin counterstain would stain both Gram positive and Gram negative cells pink.
Crystal violet would wash out of both cell types and safranin counterstain would stain both Gram positive and Gram negative cells pink.
You're measuring the number of cells in a culture by turbidometry. You measure them at 8am and then again at 10am. The turbidity of the culture is less at 10am. In what growth phase is the culture? Lag phase Death phase Exponential growth phase Stationary phase
Death phase
During which phase is generation time measured? Exponential growth phase Stationary phase Lag phase Death phase
Exponential growth phase
Why do bacteria grow at less than their optimum doubling time during the lag phase? Bacterial DNA replication is inhibited during the lag phase so bacteria are not able to divide. Many bacteria are dying during the lag phase. Bacteria are not metabolically active during the lag phase. During lag phase, bacteria are synthesizing molecules to prepare for rapid cell growth. Bacteria are overwhelmed by waste products that prevents their growth during the lag phase.
During lag phase, bacteria are synthesizing molecules to prepare for rapid cell growth.
Which of the following is TRUE about clonal selection? The lymphocyte will can be altered to respond to different antigens. Each lymphocyte has specificity to only one antigen and will react to only that antigen. Lymphocytes that respond strongly to foreign antigens will be eliminated. Self-reactive lymphocytes will expand by dividing to produce a population of clones that will respond to the same antigen.
Each lymphocyte has specificity to only one antigen and will react to only that antigen.
Often the mnemonic device "OIL RIG" is used to remember the principles of redox reactions. Oxidation Is Loss and Reduction Is Gain of what? Oxygen only Electrons Oxygen and electrons Hydrogen
Electrons
Which of the following statements regarding the Chlamydia life cycle is incorrect? The elementary body is the infectious stage of Chlamydia. Elementary bodies differentiate into reticulate bodies in the cell nucleus. Reticulate bodies multiple by binary fission. Elementary bodies are released from the host cell to continue the infectious cycle.
Elementary bodies differentiate into reticulate bodies in the cell nucleus.
Which of the following statements about Chlamydia is incorrect? Elementary bodies are the infectious form. It is gram-negative. It is an obligate parasite that needs host cells for growth. Reticulate bodies differentiate into elementary bodies. Elementary bodies lack enzyme systems for making ATP.
Elementary bodies lack enzyme systems for making ATP.
What is meant by the statement "Enzymes are biological catalysts"? Enzymes are made by all forms of life. Enzymes speed up the chemical reactions in living cells. Enzymes produce biological organisms. Enzymes produce products useful for biology. Enzymes are products of biological systems.
Enzymes speed up the chemical reactions in living cells.
If the bacteria cell plasma membrane was damaged, what step of metabolism would be affected? Breakdown of glucose to pyruvic acid during glycolysis. Formation of ATP in glycolysis. Formation of ATP in the Krebs cycle. Establishment of the hydrogen ion gradient in the Electron Transport System. Formation of NADH and FADH2 in glycolysis and the Krebs cycle.
Establishment of the hydrogen ion gradient in the Electron Transport System.
Why does a eukaryotic cell have extensive internal membrane and many membrane-bound organelles? Unlike prokaryotic cells, eukaryotic cells can make phospholipids in their endoplasmic reticulum. Eukaryotic cells are large in size and volume and must partition off areas in order to function efficiently. Internal membranes are necessary for protein production in a eukaryotic cell. Eukaryotic cells live in a phospholipid-rich environment, which enables them to make a lot of membranes.
Eukaryotic cells are large in size and volume and must partition off areas in order to function efficiently.
Why does a eukaryotic cell have extensive internal membrane and many membrane-bound organelles? Internal membranes are necessary for protein production in a eukaryotic cell. Eukaryotic cells are large in size and volume and must partition off areas in order to function efficiently. Unlike prokaryotic cells, eukaryotic cells can make phospholipids in their endoplasmic reticulum. Eukaryotic cells live in a phospholipid-rich environment, which enables them to make a lot of membranes.
Eukaryotic cells live in a phospholipid-rich environment, which enables them to make a lot of membranes.
Animal viruses have the ability to attach to and enter almost any animal host cell. True False
False
CSF contains high levels of complement and circulating antibodies to prevent infection of the brain and spinal cord. True False
False
Digestion of microorganisms occurs in phagosomes. True False
False
Your immune system does not change from the time you are born until death. True False
False
While working in a hospital you are exposed to tuberculosis by droplet transmission. Immune cells that originate from ___ in the lymphatic system will be the first responders. cervical nodes inguinal nodes GALT MALT blood vessels
GALT
Which of the following statements describes the process of horizontal gene transfer? Gaining a single new gene sequence from outside of the cell. Replication of genomic DNA to be passed on the daughter cells. DNA transferred to the next generation of bacteria from a related cell. A DNA mutation that is passed on to offspring by the process of DNA replication and cell division.
Gaining a single new gene sequence from outside of the cell.
A 30-year-old woman was hospitalized after she experienced convulsions. On examination, she was alert and oriented and complained of a fever, headache, and stiff neck. Which of the following is most likely to provide rapid identification of the cause of her symptoms? None of these would provide rapid identification. check serum antibodies Gram stain of throat culture Gram stain of cerebrospinal fluid biopsy of brain tissue
Gram stain of cerebrospinal fluid
Which of the following is NOT a mechanism of defense against microbial infection in the skin? Tightly packed epithelial cells that create an impenetrable barrier. Release of dead skin cells from the epidermis. Secretion of sebum and lysozyme to inhibits the growth of microbes. Hair follicles prevent entry of microbes into host tissues.
Hair follicles prevent entry of microbes into host tissues.
Case study 12 Your patient was admitted to the hospital in New Mexico when his condition worsened. He is severly ill with diarrhea, abdominal pain, vomiting, and low blood pressure. Yesterday, he developed massive bleeding under his skin, and bruises around his swollen lymph node. Diagnostics showed bacteremia and severe sepsis. He was treated with gentamycin, vancomycin, ciprofloxacin, doxycycline, and human activated protein C, but his condition worsened. His blood pressure dropped dramatically, and his kidneys began to fail. He was placed on mechanical ventilation and hemodialysis, and underwent unilateral amputation of one of his hands due to ischemia. What do you think is wrong with your patient? He has meningitis. He has pneumonic plague. He has MRSA. He has the a virulent strain of the flu. He has septicemic plague.
He has septicemic plague.
An antibiotic that specifically targets the 70S ribosome will have NO effect on which of the following? Human ribosomes attached to the endoplasmic reticulum Human ribosomes in the cytoplasm AND Human ribosomes attached to the endoplasmic reticulum Human ribosomes in the cytoplasm Bacterial ribosomes Mitochondria
Human ribosomes in the cytoplasm AND Human ribosomes attached to the endoplasmic reticulum
The antibodies found in mucus, saliva, and tears are IgE IgA IgG IgM
IgA
The presence of which antibody would indicate that a patient has a current infection rather than a past infection or vaccination? IgA IgG IgM IgD IgE
IgM
S. aureus has been isolated from an animal's infected wound. To satisfy Koch's postulates, what would the doctor need to do with the isolated S. aureus? Inject the S. aureus into an animal and see whether it develops the same type of infection. Inject the S. aureus into an animal; if the animal develops the same infection, isolate the infectious material from the animal and test its ability to vaccinate another animal. Inject the S. aureus into an animal, observe whether the animal gets an infection similar to the patient's, and isolate the same type of S. aureus from the infection Compare the DNA sequence of the type of S. aureus isolated from the patient to other S. aureus types from the hospital.
Inject the S. aureus into an animal; if the animal develops the same infection, isolate the infectious material from the animal and test its ability to vaccinate another animal.
Which of the following is true? It is possible to have AIDS without being infected with HIV. It is possible to be infected with HIV without having AIDS. Patients who are HIV positive but are not actively ill are not able to infect others. It is impossible to have HIV and AIDS at the same time.
It is possible to be infected with HIV without having AIDS.
Although you ate feta cheese contaminated with Listeria monocytogenes, the microbe passed through your body without activating the immune system or making you sick. Why was the monocytogenes unable to cause disease? L. monocytogenes could not find a portal of entry. L. monocytogenes did not attach to host tissues. The toxins produced by L. monocytogenes were ineffective in damaging host tissues. The L. monocytogenes was destroyed by the phagocytes. L. monocytogenes stayed in the cytoplasm of the phagocytes.
L. monocytogenes did not attach to host tissues.
What type of bacteria killed the mouse in this experiment? Live R strain Heat-killed S strain Heat-killed R strain Live S strain
Live S strain
Once inside the phagocyte, how are microbes killed? The membrane attack complex causes lysis of the microbe. Inhibition of bacteria cell wall construction. An increase in salt concentration leads to plasmolysis of the microbe. Lysozyme and digestive enzymes break apart the microbe in the phagolysosome.
Lysozyme and digestive enzymes break apart the microbe in the phagolysosome.
Case Study 12 You work at a small family practice. A man in their early fifties comes in with a complaint of intermittent fever and a minor headache. You are the physician that examines them and the only clinical finding is a wound on their thumb that does not appear infected and which they received while skinning a ground squirrel about three days ago. The patient also has several small bug bites, also not appearing infected, around the wrist of the hand with the wound. The lymph nodes at their neck are swollen but inside their throat looks normal and there are no other visible signs of illness. The patient is up to date on their vaccinations and also received the recommended shingles and influenza vaccines earlier this year. The patient has not been in contact with anyone known to be ill with an infection. Based on the limited information, which list of diseases can you eliminate? Plague and Epstein-Barr virus MRSA and Streptococcus pyogenes infection of the upper respiratory tract MRSA, Streptococcus pyogenes infection of the upper respiratory tract, and human herpesvirus-3 Meningitis and Flu Plague, Epstein-Barr virus, and HIV
MRSA, Streptococcus pyogenes infection of the upper respiratory tract, and human herpesvirus-3
The steps in Pasteur's experiment with the swan-necked flask are shown in the figure below. In step 4, the flask is tilted to allow broth to enter the neck of the flask. Why does this result in microbe growth in the broth in step 5? Tilting the flask oxygenates the broth so microbes present in it can complete respiration and grow. The broth is cooled by tilting so that microbes are able to grow in it. Microbes present in the air settle in the neck of the flask and are brought in contact with the broth when the flask is tilted. Tilting the flask shifts the microbes present in the broth from the stationary phase to the exponential growth phase so their numbers begin to increase with growth. Essential nutrients are present in the neck of the flask that microbes can access with tilting and are then able to grow.
Microbes present in the air settle in the neck of the flask and are brought in contact with the broth when the flask is tilted.
What can happen if the ciliary defense of the respiratory tract is inhibited? Mucus and microbes will enter the lungs. All first line defenses are shut down. Microbes and mucus will be swallowed. The mucous membrane would dry out.
Mucus and microbes will enter the lungs.
An electron is removed from pyruvic acid and transferred to NAD+, forming NADH. Which molecule is reduced in this reaction? electron Hydrogen NAD+ pyrivuc acid and NAD+ pyrivuc acid
NAD+
The reactions of fermentation function to produce _______ molecules for further use in glycolysis. glucose pyruvic acid NADH ATP NAD+
NAD+
Which of the organisms in the figure has the LONGEST doubling time? Escherichia coli Neisseria meningitidis Geobacillus stearothermophilus More information is required to determine doubling time.
Neisseria meningitidis
Which process involves antibodies covering surface receptors on a virus or toxin molecule, thereby disrupting their activity? Anamnestic response Opsonization Neutralization Agglutination Complement fixation
Neutralization
According to the theory of spontaneous generation, what is the source of life? Life comes from life. Nonliving matter. Microbes present in the air. An original cell from which all cells are descended.
Nonliving matter.
Which group of microorganisms requires high osmotic pressure to survive? Osmolyphiles Obligate halophiles AND Osmolyphiles Obligate halophiles Facultative halophiles Acidophiles
Obligate halophiles
What is the benefit of complementary base pairing in the DNA molecule? The replicated DNA molecules have old and new genetic information in them. It enables more codon combinations from the four base pairs. Both DNA strands can be synthesized as leading strands. One strand can serve as a template for construction of a second strand during DNA replication.
One strand can serve as a template for construction of a second strand during DNA replication.
How do the cell walls of fungi and bacteria differ? Only bacteria cell walls contain peptidoglycan. Fungi don't have cell walls because they are not cellular. Only fungi cell walls contain phospholipids. Only bacteria cell walls contain cellulose.
Only bacteria cell walls contain peptidoglycan.
When phagocytes recognize pathogens, the ___ on the surface of the phagocyte attaches to the ___ on the surface of the pathogen. PAMP, PRR PRR, PAMP PRR, PRR PAMP, PAMP
PRR, PAMP
Which of the following is NOT a type of bacterial DNA recombination? Transduction Replication Conjugation Transformation
Replication
What is plasmolysis? Shrinkage of the cell's cytoplasm caused by high osmotic pressure. Bursting of the cell due to a damaged cell wall. A pause in cellular metabolism and ATP production caused by the presence of sugar. Change in cell size as a result of cold temperatures. Oxidative damage in the cell because of the presence of oxygen.
Shrinkage of the cell's cytoplasm caused by high osmotic pressure.
What is the morphology and arrangement of the bacteria shown below? Streptobacillus Staphylococcus Spirochetes Diplococcus Staphylobacillus
Streptobacillus
All of the following are physical barriers to pathogens, except ______. hairs unbroken skin mucous T-cells tears
T-cells
What is the difference between an F+ and an Hfr cell? The Hfr has only a portion of the F factor genes while F+ has all of the F factor genes. An F+ cell has genes that enable it to extend a pilus to a recipient cell, Hfr does not. The F factor genes are present in both but are incorporated into the bacterial chromosome in Hfr cells only. An Hfr cell can be both a donor and a recipient, F+ can be only a donor during conjugation.
The F factor genes are present in both but are incorporated into the bacterial chromosome in Hfr cells only.
Which of the following most accurately describes how a pathogenic bacterium might be affected by antibodies? The antibodies may stick to multiple bacteria, causing agglutination. The antibodies may block proteins necessary for the pathogen to bind to the host, may coat the bacterium, or may agglutinate bacteria. The antibodies may coat the surface of the bacteria, allowing for it to be tagged for phagocytosis. The antibodies may block proteins necessary for the pathogen to bind to the host.
The antibodies may block proteins necessary for the pathogen to bind to the host, may coat the bacterium, or may agglutinate bacteria.
Neisseria gonorrhoeae is a Gram-negative coccus bacteria that causes the sexually-transmitted infection gonorrhea. It has a tendency to form biofilms and can horizontally exchange DNA. Based on this information, what can you conclude about Neisseria gonnorrhoeae? The cell wall of Neisseria gonorrhoeae contains peptidoglycan cross-linked into a strong mesh structure. Neisseria gonnorhoeae are oblong in shape and arranged in long chains. Neisseria gonorrhoeae have flagella that allow taxis in response to a chemical attractant The scientific name of the bacteria can be abbreviated Neisseria g. Neisseria gonnorhoeae contains several small circular DNA plasmids.
The cell wall of Neisseria gonorrhoeae contains peptidoglycan cross-linked into a strong mesh structure.
In the 1860s, Pasteur developed a new flask for his experiments on spontaneous generation. How did this help him disprove the opposing view at the time? The flask allowed microbes from the air to get into the gravy in the flask. The flask prevented microbes from getting into the gravy in the flask. The flask enabled sterilization of the gravy. He could easily break the neck of the flask.
The flask prevented microbes from getting into the gravy in the flask.
Which of the following statements regarding metabolic reactions is FALSE? Anabolic reactions build large molecules from smaller ones. ATP holds more energy than ADP in its molecular structure. Energy is released in catabolic reactions. The formation of ADP requires an input of energy.
The formation of ADP requires an input of energy.
How is the lytic cycle different from the lysogenic state with respect to the infected host cell? The viral DNA may integrate into the host genome during the lytic cycle. The host cell is allowed to live during the lytic cycle. The host cell dies during the lytic cycle. The host cell can only divide during the lytic cycle.
The host cell dies during the lytic cycle.
When is the second line of immune defense needed? The preferred portal of entry for the microbe is inhalation or ingestion. The microbe breaches the mucous membranes and gains entry into the host cells and tissues. As the last effort when the host is close to death from the infection. The host B cells are not able to create antibodies to fight the infection.
The microbe breaches the mucous membranes and gains entry into the host cells and tissues.
Which of the following statements about salmonellosis is FALSE? It is often associated with poultry products. It is a self-limiting infection. It is a bacterial infection. The mortality rate is high. A healthy carrier state exists.
The mortality rate is high.
Which of the following statements about noncompetitive inhibition of enzymes is TRUE? The noncompetitive inhibitor and substrate can be bound to the enzyme at the same time. The noncompetitive inhibitor fits into the enzyme active site. The noncompetitive inhibitor binds to the enzyme and causes the active site to change shape. Noncompetitive inhibitors only bind to the enzyme when they are present in high concentrations. The presence of a noncompetitive inhibitor would increase the amount of reaction products formed.
The noncompetitive inhibitor binds to the enzyme and causes the active site to change shape.
Which statement correctly describes the eukaryotic and prokaryotic ribosome? The eukaryotic ribosome reads A,C,G, and T base pairs while the prokaryotic ribosome reads A,C,G, and U. The eukaryotic ribosome makes mRNA and the prokaryotic ribosome makes DNA. The ribosome in the eukaryotic cell cytoplasm is larger than the prokaryotic ribosome. The eukaryotic ribosome is located only in the cytoplasm while the prokaryotic ribosome is located in the cytoplasm and in some of the cell's organelles.
The ribosome in the eukaryotic cell cytoplasm is larger than the prokaryotic ribosome.
Microbes are often identified using biochemical tests that detect specific enzymes of metabolic pathways. E. coli typically ferments lactose and produces an acid byproduct, whereas Shigella spp. (species) do not. If a pure culture of each bacterium was placed in a tube containing lactose as the only food source, and a chemical indicator that changed color after a pH change, what would the tubes look like after the bacteria were incubated? The tube with E. coli would indicate a pH change, and the Shigella tube would indicate no change. Both tubes would show the evidence of lactose fermentation by turning basic in pH. Neither tube will show any change. Both tubes would show the evidence of lactose fermentation by turning acidic and changing the pH indicator.
The tube with E. coli would indicate a pH change, and the Shigella tube would indicate no change.
A viral mutation that causes changes in the glycoprotein spikes would affect which aspect of the virus? The virus would adsorb to different host cells and its host range would be altered. The viral genome would not require uncoating once inside the host cell. The virus would become lysogenic and incorporate its genome into the host cell genome. The virus would lose its viral envelope and become a naked virus. The virus would enter the host by a combination of endocytosis and fusion.
The virus would adsorb to different host cells and its host range would be altered.
Which of the following statements regarding antibody function is FALSE? They can penetrate host cells to bind endogenous antigens They can facilitate cytolysis of cells They can facilitate phagocyte attack on a bacteria They can bind more than one pathogen at a time, forming complexes They can prevent viral attachment to a host cell
They can penetrate host cells to bind endogenous antigens
HIV attack of CD4+ T cells causes suppression of both cell-mediated and humoral immune responses. True False
True
In the Ames test, any colonies that form on the control are a result of spontaneous mutations. True False
True
The cell walls of bacteria are responsible for the difference in the Gram stain reaction. True False
True
What are the products of semiconservative replication for a double-stranded DNA molecule? Two double-stranded DNA molecules, each consisting of 1 parental and 1 daughter strand One double-stranded DNA molecule, consisting of 2 daughter strands One double-stranded DNA molecule, consisting of 1 parental strand and 1 daughter strand Two double-stranded DNA molecules, one consisting of 2 parental strands, the other consisting of 2 daughter strands
Two double-stranded DNA molecules, each consisting of 1 parental and 1 daughter strand
Which of the following violates Koch's postulates? Infection of a healthy individual with M. tuberculosis bacteria causes development of tuberculosis. M. tuberculosis is resistant to many types of antibiotic. S. pyogenes bacteria can only grow on highly nutritious media. V. cholera bacteria can be isolated from both cholera patients and healthy individuals.
V. cholera bacteria can be isolated from both cholera patients and healthy individuals.
When Robert Koch was establishing his postulates he was studying Bacillus anthracis, the bacteria that causes anthrax. If he had been studying a viral disease instead, why would it have been difficult to establish the same postulates? Viruses cannot grow outside of a host cell so it is impossible to make a pure culture of viruses in a lab AND Viruses are very small and impossible to see with the microscopes that Koch was using. Viral infections do not respond to antibiotics. Viruses cannot grow outside of a host cell so it is impossible to make a pure culture of viruses in a lab AND Viral infections do not respond to antibiotics. Viruses are very small and impossible to see with the microscopes that Koch was using. Viruses cannot grow outside of a host cell so it is impossible to make a pure culture of viruses in a lab.
Viruses cannot grow outside of a host cell so it is impossible to make a pure culture of viruses in a lab AND Viruses are very small and impossible to see with the microscopes that Koch was using.
How do the cell walls of bacteria and viruses differ? Only viral cell walls contain peptidoglycan. Only bacteria cell walls contain cellulose. Viruses don't have cell walls because they are not cellular. Only viral cell walls contain phospholipids.
Viruses don't have cell walls because they are not cellular.
Which of the following statements about viruses is FALSE? Viruses contain DNA or RNA but never both. Viruses exclusively use their own enzymes. Viruses have genes. Viruses contain a protein coat. Viruses use the machinery of the host cell.
Viruses exclusively use their own enzymes.
Which of the following is NOT a reservoir of infection? a river All of these answers can be a reservoir of infection. a sick person a chicken a healthy person
a sick person
Transformation is the transfer of DNA from a donor to a recipient cell by sexual reproduction. by cell-to-cell contact. as naked DNA in solution. by a bacteriophage. by crossing over.
as naked DNA in solution.
Fimbriae help bacteria move by twitching and gliding motility. synthesize proteins, attach and form biofilms. replicate DNA. transfer DNA to neighboring bacteria.
attach and form biofilms.
What type of vaccine is the live, weakened measles virus? inactivated whole-cell vaccine attenuated whole-cell vaccine subunit vaccine toxoid vaccine
attenuated whole-cell vaccine
Assuming unlimited resources and space, which line best depicts a facultative anaerobe grown in the absence of atmospheric oxygen? c b a
b
Which organisms can produce ATP by fermentation or anaerobic respiration? a, b, and c b, c, d, and e b, c, and d a, b, c and e a and b
b, c, and d
Which of the following is a beneficial function of microorganisms bioremediation AND microbial antagonism. opportunistic infections. microbial antagonism. virulence. bioremediation.
bioremediation AND microbial antagonism.
Microbes should NOT normally be present in which of these body sites? gastrointestinal tract skin eyes brain mouth
brain
Transduction is the transfer of DNA from a donor to a recipient cell by a bacteriophage. as naked DNA in solution. by crossing over. by cell-to-cell contact.
by a bacteriophage.
An interaction between two immune cells and an antigen is shown in the figure. Identify the immune cells. cell 1: APC, cell 2: CD4 T cell cell 1: APC, cell 2: CD8 T cell cell 1: nucleated cell, cell 2: CD8 T cell cell 1: APC, cell 2: B cell
cell 1: APC, cell 2: CD4 T cell
An example of artificial active immunity would be chickenpox infection, followed by lifelong immunity. a fetus acquiring maternal IgG to the chickenpox virus across the placenta. giving a person immune serum globulins to chickenpox virus after exposure to the disease. chickenpox vaccine triggering extended immunity to chickenpox.
chickenpox vaccine triggering extended immunity to chickenpox.
"Rice water stools" are characteristic of ulceritis. salmonellosis. Helicobacter pylori infection. typhoid fever. cholera.
cholera.
The lower respiratory tract is protected by all of the following EXCEPT competition with the normal flora of the lungs. IgA antibodies. alveolar macrophages. the ciliary escalator. mucous secretions.
competition with the normal flora of the lungs.
Which of the following statements describes a Gram-negative bacteria? only one plasma membrane contains lipopolysaccharides contains teichoic acids thick peptidoglycan layer
contains lipopolysaccharides
How could disease transmission be stopped at the portal of exit? washing hands. covering the mouth when sneezing. covering the mouth when sneezing AND wearing a condom. wearing a condom. applying antimicrobial ointment to a wound.
covering the mouth when sneezing AND wearing a condom.
You want to determine the cause of a disease affecting chickens. According to Koch's postulates, after isolating a blood sample from a sick chicken what should you do next? culture the blood in the lab to grow any microbes present in it inject blood from the sick chicken into a healthy chicken isolate blood from a healthy chicken treat the blood with antibiotics to see if the microbe is killed
culture the blood in the lab to grow any microbes present in it
Which organisms can tolerate oxygen but CANNOT perform aerobic respiration? b b, d,and e b and d d a
d
Where is H+ concentration the highest? b e a c d
e
Which tube shows the expected growth pattern for a microaerophile? a d e c b
e
The core of every virus particle always contains ______. enzymes DNA capsomeres DNA and RNA either DNA or RNA
either DNA or RNA
Most pathogens that gain access through the skin can get past the mucociliary escalator. must adhere first to mucous membranes before penetrating. can penetrate intact skin. enter through hair follicles and sweat ducts.
enter through hair follicles and sweat ducts.
Which of the following is not present in all viruses? All viruses have the same components because all are essential to virus function. receptors for adherence to host cells capsid envelope nucleic acid genome
envelope
Which of the following phases of the bacterial growth curve is matched with the correct definition exponential growth phase--the phase in which organisms are actively dividing and the generation time is constant death phase--the phase in which the curve is flat; microbial deaths balance the number of new cells lag phase--the phase in which the death of organisms exceeds the creation of new cells and the curve declines stationary phase--the phase in which cells are not dividing very rapidly as they acclimatize to a new environment
exponential growth phase--the phase in which organisms are actively dividing and the generation time is constant
In order to establish biofilms within the intestines of humans, bacteria may adhere initially to the intestinal wall using ____ before secreting a protective matrix coating. fimbrae teichoic acids flagella 70s ribosome phospholipids
fimbrae
Human breast milk contains lactoferrin, lysozyme, secretory IgA, IgG, and complement C3. Which lines of immune defense are present in breast milk? first line of defense only second line of defense only first, second, and third lines of defense third line of defense only first and third lines of defense only
first, second, and third lines of defense
All of the following events elicit an antibody response. Put them in order from step 1 to step 5 and select third step as your answer. helper T cell recognizes antigen-digest bound to MHC II helper T cell produces cytokines part of the digested antigen goes to surface of Antigen-Presenting Cell the Antigen-Presenting Cell phagocytizes antigen B cell is activated.
helper T cell recognizes antigen-digest bound to MHC II
Staphylococcus bacteria produce many enzymes that increase their virulence. Which enzyme is matched with its correct function? staphylokinase - prevents formation of ATP in the host cell adherinase - prevents antibody binding to the bacteria hyaluronidase - breaks connections between host cells and enables the bacteria to spread coagulase - breaks down host cell membrane
hyaluronidase - breaks connections between host cells and enables the bacteria to spread
Illness occurs rapidly after exposure to the flu virus because of a short ___ period, but this period is much longer in HIV where illness can take several decades to develop after exposure. illness decline prodromal convalescence incubation
incubation
A physician transmits Influenza from one patient to another patient because of viral contamination on the stethoscope. The flu was transmitted _____ via _____. directly, fomite by a vector, mechanical transmission indirectly, carrier indirectly, fomite directly, droplet
indirectly, fomite
The DNA found in most bacterial cells is linear in structure. is found in multiple copies. is surrounded by a nuclear membrane. is circular in structure.
is circular in structure.
The Streptococcus pyogenes that causes scarlet fever is different from the Streptococcus pyogenes that causes only strep throat because it produces erythrogenic toxin. it has aquired DNA by transduction. it produces erythrogenic toxin and has aquired DNA by transduction. it is a group A strep. it produces a capsule.
it produces erythrogenic toxin and has aquired DNA by transduction.
A psychrophilic bacteria is unable to grow at temperatures above 20⁰C because _______. it does not have cell wall and will burst at high temperatures its enzymes will denature and be unfunctional it will undergo plasmolysis after water rushes out of the bacteria cell it will not have a source of sugar that can be used to make ATP
its enzymes will denature and be unfunctional
Yersinia pestis infects the tissue of which of the following body systems? lymphatic system nervous system digestive system reproductive system AND lymphatic system reproductive system
lymphatic system
Phagocytes utilize all of the following to help locate and contain microorganisms EXCEPT complement. lysozyme. chemotaxis. adherence to a PAMP on the microbe surface. opsonization.
lysozyme.
A treatment for bacterial infections from the early 20th century has made a comeback; the use of bacterial viruses to eliminate bacterial infections. Which type of virus would be best to use for treating and killing a bacterial infection in humans? nonenveloped virus lytic bacteriophage enveloped virus virus with an RNA genome temperate bacteriophage
lytic bacteriophage
Helicobacter pylori can grow in the stomach because it makes urease enzyme that neutralizes HCl. makes HCl that raises the stomach pH. makes a capsule. hides in macrophages.
makes urease enzyme that neutralizes HCl.
A house fly transmits tularemia by carrying tularensis on its feet. This is an example of droplet transmission. mechanical transmission. biological transmission. vehicle contact transmission. indirect contact transmission.
mechanical transmission.
Viruses exhibit all the following except ______. smallest size among all microbe groups metabolism genes ability to infect host cells definite shape
metabolism
Genetic change in bacteria can be brought about by transduction and conjugation. mutation. transformation and conjugation. mutation,conjugation, transduction, and transformation. conjugation.
mutation,conjugation, transduction, and transformation.
Wood-eating termites in the genus Reticulitermes cannot digest the cellulose in wood, but the protozoan Trichonympha, which lives in their intestine, can digest cellulose. Both organisms derive nutrients from the digested cellulose. What type of symbiotic relationship do the termites and protozoa maintain? mutualism commensalism pathogenism synergism parasitism
mutualism
Inhibitors that bind away from the enzyme's active site to prevent substrate binding to the enzyme are noncompetitive. coenzymes. denatured. competitive. ions.
noncompetitive.
There were five major cholera outbreaks in the 1800's that occurred all over the world and killed nearly 40 million people. During this time period, cholera can be classified as a(n) _____ disease. endemic pandemic epidemic sporadic
pandemic
Which structure is involved in bacteria motility AND horizontal gene transfer? fimbrae peptidoglycan pili glycocalyx flagella
pili
Table 8.1 Colony count on plates from Ames test of a control and three different potential mutagens Sample Number of bacteria colonies on minimal media plate Control 3 Potential mutagen 1 1 Potential mutagen 2 63 Potential mutagen 3 28 From the data in Table 8.1, which of the samples are mutagens? potential mutagen 1 potential mutagen 2 potential mutagens 2 and 3 potential mutagen 3 potential mutagens 1 and 3
potential mutagens 2 and 3
Innate immunity includes all of the following EXCEPT production of antibody. phagocytosis. inflammation. fever.
production of antibody.
The circulating substances that affect the hypothalamus and initiate fever are ______. interferons complement lysozymes histamine pyrogens
pyrogens
Refer to the table. Bacteria culture A is most likely in the _____ growth phase and bacteria culture B is most likely in the ____ growth phase. Number of cells at time 1 Number of cells at time 2 Bacterial culture A 152 150 Bacteria culture B 562 36 death, lag log, death lag, stationary stationary, death death, birth
stationary, death
A characteristic symptom of plague is nausea and vomiting. small red spots on the skin. swollen lymph nodes. recurrent fever. rose-colored spots.
swollen lymph nodes.
Which of the following is the best definition of generation time? the time needed for nuclear division the length of time needed for a cell to divide the maximum number of bacteria the length of time needed for lag phase the duration of log phase
the length of time needed for a cell to divide
What is "2"? formation of water the path of H+ FADH2 reduction production of ADP production of ATP
the path of H+
Select the best definition of microbial antagonism. the presence of pathogens on the surface of the skin, which will invade the body via abrasions the presence of resident microbiota on the surface of the body and in cavities that connect to the surface the presence of normal microbiota that protect the body by competing with pathogenic microbes in a variety of ways the presence of normal microbiota that can become pathogens under certain circumstances
the presence of normal microbiota that protect the body by competing with pathogenic microbes in a variety of ways
Figure 1 shows the antibody response in a host following antigen exposure. Based on the figure, you can conclude that the antigen in the initial exposure and in the secondary exposure was _____. recognized by memory B cells each time the same antigen more concentrated in the secondary exposure more virulent in the secondary exposure
the same antigen
Which of the following pairs of microbe classification terms and optimal growth temperatures is mismatched? psychrophile, 15°C mesophile, 37°C hyperthermophiles, 90°C thermophile, 25°C
thermophile, 25°C
What is the overall goal of metabolism? to produce sugars to prevent the formation of fat in the cell to make ATP to make a gradient of H+ ions across the inner mitochondrial membrane to produce high-energy electrons
to make ATP
Conjugation differs from reproduction because conjugation transfers DNA vertically to new cells. transfers DNA horizontally to nearby cells without those cells undergoing replication. transcribes DNA to RNA. copies RNA to make DNA. replicates DNA.
transfers DNA horizontally to nearby cells without those cells undergoing replication.
A 45-year-old man has pus-filled vesicles distributed over his back in the upper right quadrant, over his right shoulder, and upper right quadrant of his chest. His symptoms are most likely due to Candida albicans. varicella-zoster virus. Staphylococcus aureus. Streptococcus pyogenes. herpes simplex virus.
varicella-zoster virus.
A 45-year-old man has pus-filled vesicles distributed over his back in the upper right quadrant, over his right shoulder, and upper right quadrant of his chest. His symptoms are most likely due to Streptococcus pyogenes. bubonic plague. MRSA. varicella-zoster virus. HIV.
varicella-zoster virus.
Genes can be shared between organisms by horizontal or vertical gene transfer. Humans are capable of _______ gene transfer and bacteria are capable of ________ gene transfer. horizontal, both horizontal and vertical vertical, vertical horizontal, vertical vertical, both horizontal and vertical
vertical, both horizontal and vertical