Microbio Homework Answers

Which of the following is used to classify viruses? i. Nucleic acid ii. Shape iii. Size iv. Host range v. Biochemical tests

(i), (ii), (iii), and (iv)

Select the TRUE statements regarding reverse-transcribing viruses. (NOTE: Please change all question marks to checkmarks for correct answers or empty boxes for incorrect answers.)

- they have a unique enzyme called reverse transcriptase -their replication strategy goes against the central dogma of genetics -they exhibit high mutation rates in their genomes

The antibiotic tetracycline inhibits protein synthesis in bacteria. Based on this information, which are the most likely targets for the drug in these cells?

-30S ribosome subunits -80S ribosomes -40S ribosomes subunits -60S ribosome subunit -Peptidoglycan

What three general products of the central metabolic pathways does a cell require to carry out biosynthesis?

-ATP -NADPH -Precursor metabolites

The three central metabolic pathways—glycolysis, the pentose phosphate pathway, and the tricarboxylic acid cycle (TCA cycle)—modify organic molecules to generate what three useful components for the cell?

-ATP -Reducing power -Precursor metabolites

Which of the following leads to emerging infectious diseases? Check all that apply

-Antibiotic misuse -failure to vaccinate -horizontal gene transfer -COVID-19 -changing lifestyles

Which of the following genes are likely to be found on a plasmid rather than on the bacterial chromosome? (NOTE: Please change all question marks to checkmarks for correct answers or empty boxes for incorrect answers.)

-BT toxin gene -Chloramphenicol-resistance gene -Oil degradation enzyme genes

Place the steps for the proposed mechanism by which prions propagate in the correct order. Not all labels are used.

-Both normal (PrPc) and abnormal (PrPsc) proteins are present -PrPsc interacts with PrPc -PrPc is converted into PrPsc -conversion continues and PrPsc accumulates

Please select all of the differences between DNA and RNA to test your understanding of these nucleic acids.

-DNA is double-stranded, RNA is single-stranded. -DNA nucleotides contain deoxyribose whereas RnA nucleotides contain ribose -There are multiple types of RNA with different functions whereas there is only one type of DNA

Which of the following are enzymes involved in anabolic reactions?

-DNA polymerase- generates DNA -RNA polymerase- generates RNA -DNA ligase- joins DNA fragments -ATP synthase- generates ATP

Which of the following chemicals is/are suspected carcinogens?

-Ethylene oxide -Formaldehyde

Compare and contrast the characteristics of viruses, viroids and prions by placing the statement into the appropriate columns

-Genetic material - viruses: DNA or RNA genome viroids: RNA genome only prions:No genetic material -Host- viruses: Certain members can infect plants, animals, and even bacteria viroids: members can only infect plants prions: members can only infect certain animals -Composition- viruses: Composed of nucleic acids surrounded by protein viroids: composed of naked RNA only prions: composed of only proteins

Please select the CORRECT statements regarding the central metabolic pathways.

-Glycolysis converts one 6-C molecule of glucose to two 3-C molecules of pyruvate -Carbon from glycolysis enters the TCA cycle in the form of acetyl-CoA -The TCA cycle yields ATP, precursor metabolites and reducing power -Glycolysis produces more precursor metabolites than the TCA cycle -In the transition step, pyruvate is converted to acetyl-CoA

Select three main points from the summary.

-New York state has the highest number of cases of zika virus disease in the U.S. -New York State had 715 cases of Like virus disease in September, 2016 NYS Health + Hospitals have created a Zika plan has responding to zika virus infections -A good emergency preparedness and response program can help health care system limit the effects of Zika virus -The Zika program was created using a similar approach designed in 2014 to screen patients for possible exposure to Ebola virus disease

Please select all the TRUE statements regarding the effects of penicillin

-Penicillin inhibits enzymes involved in peptidoglycan synthesis -Penicillin generally affects Gram-positive cells more than gram-negative cells -Mycoplasma species are naturally resistant to penicillin

Which of the following statements about polymerases are INCORRECT?

-RNA polymerase synthesizes a new strand of RNA from an amino acid template -RNA polymerase can only add nucleotides to an existing nucleotides sequence

Arrange the following experiments from the oldest to the most recent in the scientific journey towards disproving spontaneous generation

-Redi's experiment -Needham's experiment -Spallanzani's experiment -Pasteur's experiment

What two approaches have previously been taken to reduce the rapid diffusion of siRNA out of the hydrogel?

-Reducing the pore size of the gel -Chemically modifying the gel to trap the siRNA

Which of the following statements regarding bacterial genetics is/are TRUE? (NOTE: Please change all question marks to checkmarks for correct answers or empty boxes for incorrect answers.)

-a change in genotype can change the phenotype -an auxotroph has a different genotype than a prototroph -an auxotroph has a different phenotype than a prototroph

You leave several tomatoes in your fridge when you go on vacation. When you get home, the tomatoes are covered in microbial growth. Select ALL the characteristics you can assign to these microbes

-aerobic -facultative anaerobes -psychrotrophs -catalase-negative -Gram-positive

Which of the following describe prokaryote cells? Select all correct choices

-always single-celled -no membrane-bound nucleus -smaller than eukaryotes

Rank the following in order of size with 1= smallest and 8= largest

-amino acid -prion -virus -bacterium -red blood cells -amoeba -helminth -mushroom

Select all the correct statements regarding autoclaving

-autoclaving involves the use of both temperature and pressure -adding pressure to the autoclave increases the temperature of the steam in it -autoclaving is consistently effective in sterilizing most objects -biological indicators such as heat-resistant endospores are used to ensure that an autoclave is working properly

Check all statements that apply to the bacterial cytoplasmic membrane

-barrier to large compounds -barrier to water -proton motive forces -contains aquaporins -composed of polysaccharides

Identify all the statements that describe positive applications of microbiology

-bioterrorism -food production -biodegradation -commercial productions -food spoilage

Select the ways that plant viruses can infect plants. (NOTE: Please change all question marks to checkmarks for correct answers or empty boxes for incorrect answers.)

-by contaminating insects feeding on plant cells and disrupting the cell wall -by soil that was previously used to grow infected plants -through grafting infected plant tissue onto healthy tissue

Which of the following are considered the major elements that primarily make up components of cells in microorganisms and all living things?

-carbon -oxygen -hydrogen -nitrogen -sulfur -phosphorus -potassium -magnesium -calcium -iron

Match the material cell shape with the correct image. There is no image for one of the shapes

-coccus -vibrio -spirochete -bacillus

Which of the following are NOT outcomes of antigen-antibody binding?

-complement neutralization -central tolerance

The compounds secreted or delivered by the T cell shown in the figure lead to (NOTE: Please change all question marks to checkmarks for correct answers or empty boxes for incorrect answers.)

-death of the infected cell -alerting neighboring cells to the presence of virus

Select which of the following led scientists to conclude that mitochondria and chloroplasts from bacterial cells. Mitochondria and chloroplasts...

-divide by binary fission -contain some genetic material -contain 70S ribosomes

Check the TRUE statements about fever induction and outcomes. (NOTE: Please change all question marks to checkmarks for correct answers or empty boxes for incorrect answers.)

-fever is induced by cytokines called pyrogens -fever inhibits bacteria from growing by inhibiting their metabolism -fever results when macrophages detect microbial invaders and release pro-inflammatory cytokines -pyrogens have an effect by acting on a certain part of the brain

A population of bacteria is breaking down some lipids to support microbial growth. Where do the products of lipid breakdown enter the central metabolic pathways?

-glycolysis -TCA cycle

The breakdown products of proteins can enter which of the following metabolic pathways?

-glycolysis -TCA cycle -Pentose phosphate pathways

Which of the following are immunotherapies for immunological disorders?

-interfering with TNF function -reducing the number of B cells -inhibiting pro-inflammatory cytokine release -interfering with lymphocyte migration -triggering apoptosis of lymphocytes

Select the FALSE statements regarding the use of irradiation for sterilizing foods

-irradiation replaces the need for other food-safety techniques -irradiation introduces carcinogens into food -irradiated products are radioactive and dangerous to eat

What are the problems with using siRNAs to target tumors

-it is difficult to get the siRNA drug to the target tissue -siRNA drugs may not enter the target cells efficiently

Which of the following are considered physical (versus chemical) factors that contribute to the skin and mucous membranes protective role against infection?

-layers of cells -mucociliary escalator -flushing of urinary tract

Which of the following are secondary lymphoid organs (areas where mature lymphocytes become activated)? (NOTE: Please change all question marks to checkmarks for correct answers or empty boxes for incorrect answers.)

-lymph nodes -peyer's patches -tonsils -spleen

A eukaryotic cells that is involved in synthesizing large amounts of protein might be expected to have

-many ribosomes -many chloroplasts -a lot of rough endoplasmic reticulum -a lot of smooth endoplasmic reticulum

Select all of the following that apply to a secondary response to a T-dependent antigen: (NOTE: Please change all question marks to checkmarks for correct answers or empty boxes for incorrect answers.)

-may take only 2-4 days to build a substantial amount of antibodies in the blood stream -Produces mainly either IgG or IgA antibodies without shifting to other types. -Fine-tunes and increases strength of binding of antibody to antigen through the process of affinity maturation.

Botulism is described as a neuroparalytic illness. Knowing this, which of the following do you think are likely to be associated with this illness?

-muscle weakness -fever -blurred vision -coughing and sneezing -slurred speech

Which of the following would be an example of occupational exposure for a healthcare worker?

-needle stick -cut with sharp object such as scalpel -contact of mucous membranes with blood

Select which of the following are applications of fluorescent staining

-observing a subset of cells within a larger population -distinguishing between live and dead cells -Identifying bacteria by tagging unique surface proteins

Imagine you want to use an enrichment culture to attempt to isolate individual species of cyanobacteria from Greenlake. You set up a flask with an appropriate nutrient solution and a small sample of lakewater, cover the flask loosely with a cap that is not airtight, and place the flask under a source of light. Which of the following would you NOT include in your culture medium so that you would encourage the growth of cyanobacteria relative to other microorganisms?

-phosphorus -nitrogen -iron -carbon -sulfate -potassium

Which of the following statements about plant virus transmission are TRUE? (NOTE: Please change all question marks to checkmarks for correct answers or empty boxes for incorrect answers.)

-plant viruses enter their host through wounds -grafted plants may be at risk of virus infection -an insect may transmit viruses between plants -parasitic fungi may transmit plant viruses

Normal microbiota plays a number of essential roles. including

-preventing disease by competing with disease-causing microbes -helping degrade foods that would otherwise be undigestible -promoting immune system development -causing disease ender certain circumstances causing autoimmunity and hypersensitivity

Where would you find nitrogen in a cell? Select all correct answers

-proteins -nucleic acids -cell wall -lipopolysaccaride

Identify what investigations would need to be done to eliminate the possibility that patient A contracted hepatitis C by occupational exposure at the facility where she worked.

-reviewing records for all patients at the facility -onsite inspection of the facility for evidence of HCV -observation of the safety practices used by staff at the facility

Please select the methods that are used to cultivate animal viruses. (NOTE: Please change all question marks to checkmarks for correct answers or empty boxes for incorrect answers.)

-se of cell culture techniques -use of animal inoculation -inoculation of embryonate eggs

In which of the following sites would you expect to find normal microbiota? (NOTE: Please change all question marks to checkmarks for correct answers or empty boxes for incorrect answers.)

-skin -vagina -colon

Ionizing radiation produces which of the following are oxygen derivatives that are harmful to bacteria?

-superoxide -hydrogen peroxide

Select all of the statements that apply to a primary response to a T-dependent antigen: (NOTE: Please change all question marks to check marks for correct answers or empty boxes for incorrect answers)

-takes 10-14 days to build s substantial amount of antibodies in the bloodstream -Produces mainly IgM antibodies, but undergoes class switching to other classes near the end of the response -Fine-tunes and increases strength of binding of antibody to antigen through the process of affinity maturation

Select the TRUE statement(s) about the figure.

-the cell could be any nucleated cell -a NK cell can recognize and induce the cell in panel 2 to undergo apoptosis

The researcher inoculates the test population of bacteria onto glucose salts agar containing penicillin and also on nutrient agar containing penicillin. She counts 25 colonies on the glucose salts plate lacking histidine and 32 colonies on the nutrient agar. Which of the following statements is TRUE? (NOTE: Please change all question marks to checkmarks for correct answers or empty boxes for incorrect answers.)

-the colonies on both plates contain penicillin-resistant mutants -the glucose salts plate contains some mutants

Consider the figure and check the CORRECT statements. (NOTE: Please change all question marks to checkmarks for correct answers or empty boxes for incorrect answers.)

-the nuclease shown in yellow should be C -The CH3 groups alert the mismatch repair system to with DNA strand is the template strand -without the CH3 groups, it is possible that the mismatch repair system would replace the G nucelobase (purple arrow) with an A

Consider the image you labeled showing a metabolic pathway under allosteric regulation. Imagine if the final enzyme in the pathway was under allosteric regulation instead of the first. What impacts would this have?

-there would be a buildup of intermediate b -The reaction would be less efficient

Which of the following facilitated the persistence of M. abscessus in the water lines at Practice A?

-these bacteria are not destroyed by commonly used disinfectants -the water lines at the practice were not flushed with bleach regularly -M. abscessus can form biofilms that are difficult to remove.

Select the reasons sugar or salt can be used for food preservation. Check all that apply

-they dehydrate the bacterial cells -they create a hypertonic environment, unfavorable for growth -they may cause plasmolysis

Which of the following suggested to the doctors in this case that a biofilm was involved in the treatment failure? Check all that apply

-they observe fungal cells on the brain shunt, despite 4 years of anti fungal therapy -they detect a biofilm in the patient's CSF using microscopy and DNA analysis techniques - they detect a biofilm in the patients inflamed meninges using microscopy and DNA analysis techniques

Arrange the events involved in sporulation by matching the descriptions with the correct picture

-vegetative growth stops; DNA is duplicated -a septum forms, dividing the cell asymmetrically -a forespore is formed within the mother cell -peptidoglycan-containing material from between the two membranes of the forespore -mother cell is degraded and the endospore is released

Once a cell detects viral RNA and produces IFNs, a sequence of events occurs. Place these steps in the correct order.

1- IFN diffuses out of the infected cell and attaches to receptors on healthy neighboring cells. 2-IFN stimulates healthy neighboring cells express inactive antiviral proteins (iAVPs). 3-iAVPs become activated by the presence of viral dsRNA in the newly infected cell 4-Activated AVPs degrade mRNA, stopping protein synthesis and causing apoptosis of newly infected cell

Please place the following events in transcription in the correct order

1- RNA polymerase binds to the promoter region just upstream of the gene. 2-RNA polymerase unwinds the DNA at the promoter site and begins to transcribe the template strand of DNA. 3-RNA polymerase moves along the template strand of DNA adding complementary RNA nucleotides, extending the mRNA. 4-Transcription continues until a terminator site in the DNA is reached. 5-The mRNA transcript is released

Place the statements about T-cell activation in the correct order.

1- dendritic cells recognize and take up antigen 2- Antigen fragments are presented with MHC molecules on the dendritic cell cytoplasmic membrane 3-Naïve T cells recognize and bind the antigen-MHC complexes on dendritic cells also displaying co-stimulatory molecules. 4-Activated T cells proliferate and differentiate. Anergic T cells undergo apoptosis.

In a bacteriophage plaque assay, the following steps are taken to enumerate phage particles. Place the steps in the correct order.

1- regular bacterial growth plates are prepared 2-Dilutions of virus samples are prepared 3-host bacteria and dilution of viral sample are mixed in liquid soft-agar 4-mixture is poured on top of plate and allowed to harden 50plates are incubated overnight 6- circular zones of learning in bacterial growth are observed and counted 7- number of zones of learning multiplied by the inverse of the dilution factor to get PFUs/milliliter in original sample

Please place the steps for animal virus replication in the correct sequence.

1- virus attaches to receptors on the host cell cytoplasmic membrane 2-virus enters the host cell by fusion or endocytosis 3-viral genome I uncoated 4-structural and catalytic viral genes are expressed 5- multiple copies of the viral genome are synthesized 6- new viral particles assemble and mature 7- viruses are released from the host cell by budding or during apoptosis of the host cell

Please rank the following from LEAST resistant to killing to MOST resistant to killing

1-enveloped viruses 2-Non-enveloped viruses 3-Pseudomonas species 4-Mycobacterium species 5-Protozoan cysts 6-Bacterial endospores 7-prions

Chlorine is safely used to disinfect waste liquids, some medical instruments, and various surfaces. It is readily available in liquid household bleach but bleach must be diluted because high concentrations are toxic and corrosive. To obtain an effective concentration of chlorine when using household bleach, a 1:100 dilution is made. This means that ______ mL of bleach is added to ______ mL of water.

1.0/99

In a one D process, how many D values would it take to reduce a population of 1010 cells to one survivor?

10

The generation time of Mycobacterium tuberculosis is

12 hours

Approximately what percentage of the total filtrates examined in this research contained biologically active compounds?

15%

Arrange the following events in clonal selection in the correct order:1. Helper T cells are activated.2. Macrophages ingest antigen.3. B cells differentiate into plasma cells and memory cells.

2,1,3

A thermophile is grown at two different temperatures. Which results would be expected for this organism?

220 minutes at 42°C; 20 minutes at 65°C

DNA polymerases use their ______ activity to remove a mismatched base pair.

3' -> 5' exonuclease

Arrange the following in the proper order in which they first appear in the alternative pathway of complement activation. 1. Factor B 2. Factor D 3. C3

3,1,2

During glycolysis, a single 6-carbon molecule of glucose is converted to two 3-carbon pyruvate molecules. During the later steps in this process, how many molecules of ATP are generated?

4

What is the antibody titer in a sample when there is a detectable antigen-antibody reaction in the 1:20 dilution, 1:40 dilution, but not in the 1:80 dilution?

40

The decimal reduction time is the time it takes to kill 90% of a given bacterial population under certain conditions. If 90% of a population of 100,000 bacteria is killed in 10 minutes, how long would it take to reduce the population to 10 cells?

40 minutes

Calculate the total amount of vancomycin received by the patient in this case, given that standard antibiotic treatment for C. difficile infections is 125 mg of vancomycin four times daily.

5 g

You suspect your patient has mumps. You take a blood sample and make 2-fold dilutions, then add mumps antigen to each dilution. A detectable antibody-antigen reaction is noted up to a dilution of 1:64 but not at 1:128. How many dilution steps did it take to get this result, and what is the antibody titer?

7 steps, titer of 64

What proportion of the confirmed measles cases were in children old enough to have received at least one dose of the MMR vaccine

77%

Consider a culture of E. coli growing in exponential phase with a generation time of 20 minutes. Beginning with 2 x 106 cells per ml, how long will it take the culture to reach a density of about 3.2 x 107 cells per ml?

80 minutes

Immunity to superinfection (infection of a cell at a later time with a second, identical bacteriophage) is a consequence of lysogeny. Why does this occur?

A repressor produced by the first virus will actively suppress the lytic cycle of the second virus.

Which regions of the gene (or segment of DNA) shown here encodes the amino acid sequence of a protein?

A,C,E

In the figure, what are the correct terms for the regions labeled "A" and "B"?

A: Promotor; B:Terminator

The Calvin Cycle uses ______ and ______, produced in the light reactions of photosynthesis, to drive the fixation of carbon dioxide.

ATP and NADPH

The pressure in a Mariana Trench is approximately 15,750 psi (pounds/inch2). Atmospheric pressure is a thousandth of this. What then, is atmospheric pressure?

About 15 psi

If an organism lost the ability to make primate, what would it be unable to do?

Add a short sequence of complementary RNA to the existing DNA strand

How could this type of scenario be avoided in the future?

All equipment/supple carts in healthcare facilities should be disinfected between procedures.

Why was the ELISA assay used to determine if patients had contracted hepatitis C

All of the choices are correct

antigen-presenting cells

All of the choices are correct -may be B cells -may be dendritic cells -may be macrophages -present antigen fragments on tier surface

The advantageous genes that can be transferred by transduction are genes for

All the answer choices are correct

Tissue injury leading to inflammation can be due to

All the answer choices are correct -chemical injury -infection -mechanical injury

Please select the INCORRECT statement regarding gene regulation.

An activator-binding site is a protein sequence that precedes an ineffective promoter, to which an activator binds to facilitate transcription.

Select the INCORRECT statement regarding checkpoint inhibition

Antibodies that bunds the CTLA-4 receptor allow TH cells to recognize and destroy cancer cells

Please match the statements to the terms they describe to test your understanding of the possible end results of antibody binding antigen.

Antibody-dependent cellular cytotoxicity (ADCC)- IgG molecules attach to a cell targeting it for attack by a NK cell Cross-linking- Formation of large Ab-Ag complexes as a result of the Ab binding two separate antigens Neutralization- Antibodies fill the surface receptors on microbe to prevent attachment to the host Complement system activation- Immune complexes activate complement proteins, leading to inflammation and production of MACs Immobilization and prevention of adherence- Antibodies bind to flagella preventing movement or to pili preventing attachment of bacteria Opsonization- Coating of microbe with antibody to enhance phagocytosis

Review the chart*. How many total bacteria are on the hands of the people who wash their hands with water only, assuming that each colony arises from a single cell?

Approximately 450

Which pair has members that are most similar in appearance?

Archaea and Bacteria

Why must fresh cells be used for the gram stain?

As cells age, they many not stain correctly

Why is autoclaving better than boiling for sterilizing microbiology equipment and media?

Autoclaves use pressurized steam, so can achieve a higher temperature than boiling water

Which of the following is part of the body's adaptive defense?

B cells

In the scientific names below, which designates the STRAIN? Escherichia coli B12 Bacillus subtilis E. coli Escherichia B. subtilis

B12

ou are a researcher investigating a highly easily spread novel pathogen. There is no treatment for the disease caused by the pathogen, and between 50% and 70% of people who acquire it are known to die from the infection. Which biosafety level laboratory do you think you should be working in?

BSL-4

Identify the correct matching of shapes, based on the scientific names

Bacillus species-rod; Staphylococcus species- spherical

You check a Gram-stained sample using a light microscope, and see long chains of round, purple cells. What would be the best choice for destroying this organism?

Bactericide

Father Spallazani repeated John Needham's experiment but Spallazani boiled the broth for much longer and sealed the flasks by melting their necks closed. He observed that the broth remained sterile, basically forever. What do you think the vast majority of the people believed from his experiment?

Because the flask of broth was sealed, the vital forces of life could not enter the flask

Identify the type of bacterial formation being shown in this image

Biofilm

What is the most important point in the first paragraph?

Biologists thought that yeast cells multiplying in grape juice convert sugar into CO2 and alcohol

Which of the following involves genetically modifying bacteria to produce compounds useful to humans?

Biotechnology

Which of the following is a primary lymphoid organ?

Bone marrow

What term refers specifically to the process shown in the figure?

Budding

Consider the the growth of E. coli in a closed system containing glucose and lactose. If lactose WAS NOT present in the system, which line best represents the growth of the bacteria?

C

You are given a Gram-positive, motile, anaerobic streptococcus to study. Which of the following best describes this organism?

Chains of round cells with a thick peptidoglycan cell wall, flagella and no oxygen requirement

Which of the following descriptions fits a chronic viral infection?

Characterized by continuous production of low levels of viral particles, potentially even in the absence of active symptoms of disease. The organism is usually still highly infectious during this time.

Which event occurs in the early stages of inflammation?

Chemical mediators and cytokines are released from injured cells

The researchers were also able to grow Sulfurospirillum halorespirans using hydrogen gas as an electron donor and acetate as a source of carbon, using perchloroethylene (PCE) as an electron acceptor. When demonstrating growth in this manner, how would scientists classify this species?

Chemoorganoheterotroph

The researchers were also able to grow Sulfurospirillum halorespiransusing hydrogen gas as an electron donor and acetate as a source of carbon, using perchloroethylene (PCE) as an electron acceptor. When demonstrating growth in this manner, how would scientists classify this species?

Chemoorganoheterotroph

Consider the growth of L. methylaminiphilus on methylamine. How would you classify this species based on its metabolism?

Chemoorganoheterotrph

What is the name of the process by which phagocytes move towards microbial products?

Chemotaxis

Which of the following are possible labels for A and B?

Chickenpox (A) and shingles (B)

lease match the organism with its fermentation product.

Clostridium-Butyric acid Lactobacillus-Lactic acid Saccharomyces-Carbon dioxide E. coli- Mixed acids Proprionibacterium-Propionic acid

Which of the following is part of the body's sensor systems?

Complement proteins

UV light and other non-ionizing radiation damage DNA molecules by

Creating thymine dimers between adjacent thymine nucleases in the DNA chain

Where does the TCA cycle take place in bacteria?

Cytoplasm

Eliminating which of the following structures would ALWAYS cause a cell to die?

Cytoplasmic membrane

Please place the statements into the correct columns to show your understanding of T cells.

Cytotoxic T cell -recognizes antigens presented on MHC class I molecules -Also called CD8 T cells -Responds to endogenous antigens -Not targeted by HIV -Destroys target cells by releasing "death packages" Helper T cells -recognizes antigens presented on MHC class II molecules -Also called CD4 T cells Responds to exogenous antigens -can be targeted by HIV -releases cytokines to activate B cells or macrophages

Consider the figure below. Which step/component of phagocytosis is/are affected by the genetic defect causing CGD?

D

What type of molecule(s) could the following be? Check all that apply. AGCGCCGCAACGC

DNA and RNA

Why is a primase needed for DNA replication?

DNA polymerase can only add nucleotides to an existing nucleic acid fragment.

If you know the sequence of nucleotides in mRNA, you can deduce the DNA sequence it was transcribed from

DNA → RNA → protein

Please match the description with the type of novel vaccines, to show your understanding of progress made in immunization

DNA-based vaccines- segments of naked DNA from infectious organisms injected into muscle Peptide vaccines-composed of key antigenic peptides from disease-causing organisms Edible vaccines- Plants with genes encoding key pathogenic components

What parameter did the researchers use to assess a filtrate as having biological activity?

Detection of morphological changes in at least 60% of tested embryos

Which of the following is NOT listed in this article as a symptom of meningitis?

Diarrhea

What general type of staining is used to separate various types of bacteria based on their cellular structures?

Differential

Which of the following cell arrangements is described CORRECTLY?

Diplococcus- pairs of spherical cells

Choose which of the following best describes the difference between a disinfectant and an antiseptic

Disinfectants are antimicrobial chemicals used on inanimate surfaces or objects to remove most of the pathogenic microorganisms. Antiseptics are antimicrobial chemicals that can be used on skin or tissues to achieve the same result.

Which of the following media did the authors use in their research?

EMB, blood and MacConkey agars

Where do NADH and FADH2 go after being produced in the TCA cycle?

Electron transport chains

In eukaryotes, proteins destined for secretion contain a signal sequence that will cause ribosomes to dock onto which of the following cellular structures?

Endoplasmic reticulum

Clostridium botulinum, the bacterium that causes botulism, is a rod-shaped, endospore-forming, toxin-producing organism. Which is true about endospores?

Endospores allow bacteria to withstand adverse conditions

How do you think the scientists isolated L. methylaminiphilus from the sediments, knowing that a single gram of soil may contain thousands of different species of bacteria?

Enrichment cultures

Please choose the term describes a virus that has a lipid bilayer (derived from the host cell) surrounding its capsid

Enveloped virus

Consider the image you labeled showing a metabolic pathway under allosteric regulation. Which enzyme in this pathway is most likely under allosteric control?

Enzyme a

Which of the following statements regarding transcription and translation is TRUE?

Eukaryotes must splice out introns following transcriptions, while prokaryotes do not

Which of the following serological methods is used to enumerate and sort specific cell types?

FACS

Please match the statements to the term they describe to test your understanding of the structure of an antibody molecule.

Fab-the two arms that bind to antigen Fc-Part of antibody involved in binding to various cells and molecules of the immune response Hinge region- region between Fab and Fc that allows swiveling of the Fab Disulfide bonds- holds polypeptide chains together

Which of the following ways in which molecules move across a membrane does not require energy?

Facilitated diffusion

After a B cell is activated to form plasma cells, those plasma cells each produce different antibodies.

False

All biochemical pathways have the same number of enzymatic reactions

False

An objective response depends on a patient's perception of improvement and cannot be measured

False

Bacteria are only visible when using an electron microscope

False

Bacteria that look alike are probably members of the same species

False

Generalized transduction involves the transfer of phage genes from one bacterial cell to another

False

Germination is one process by which bacterial cells can reproduce

False

Handwashing with regular soap removes all normal microbiota from the skin

False

If 19 students in a. class of 53 receive the measures vaccine, the remaining students in the case will be protected from the measles by herd immunity

False

In anaerobic respirations, the terminal electron acceptor would be oxygen

False

In general, bacterial cells are larger than human cells

False

In prokaryotes and eukaryotes, the TCA cycle takes place in the mitochondria

False

Mark and Peter both show increasing antibody titers over the period of time shown in the table. From these results, it can be assumed that they both developed the signs and symptoms of the disease caused by Pathogen A.

False

None of the people with measles in this case died, proving that measles is a mild, insignificant childhood disease

False

One plasma cell will secrete antibodies of various classes but the antibodies will all have different specificity

False

Protamine performed better than commercially available products as a contact lens disinfectant

False

Regarding use of heat to control microbial growth, dry heat at lower temperatures is s effective as moist heat at the same temperatures

False

T-even phages can replicate independently of a host cell

False

The bacterial cell that loses its plasmid will no longer be able to survive

False

The plus (+) strand of DNA acts as a template during transcription

False

There are no antigens that can stimulate B cells without T cell help

False

Why were people still so unwilling to dismiss spontaneous generation even after Father Spallanzani's experiment

For about 1,900 years, spontaneous generation was shown to be "true" by repeating observations

Why does Aggregibacter actinomycetemcomitans synthesize leukotoxin A?

For self-defense—the toxin protects the bacterium against phagocytes such as neutrophils

Which of the following scientists first challenged spontaneous generation?

Francesco Redi

How did the patients in this case acquire M. abscessus?

From contaminated water used during the dental procedure

You have an unknown pathogen. Chemical analysis of the microbe indicates that it is composed of DNA, RNA, lipid and protein. It also contains chitin. What would be the most appropriate agent for destroying this pathogen?

Fungicide

Match each word/phrase with its definition

Generalized transduction- Transduction resulting from a packaging error Temperate phage- phage the is able to incorporate its genome into the host chromosome Virulent phage- Phage that lyses the bacterial host when completing its life cycle Acute infection-infection in which a virus multiples rapidly and spreads in the host Specialized transduction- Transduction resulting from an error in excision of a prophage

Select the statement that most accurately defines the strains in a scientific name

Genetic variants within a species

On which of the following plates do you predict E. coli would grow the most slowly?

Glucose-salts agar

Which of the steps shown in found in the endospore and acid-fast stains but NOT in a simple stain or Gram stain

Heat during primary stain

Please classify the statements about polio vaccines to demonstrate your understanding of the global campaign to eliminate poliomyelitis.

IPV- -inactivated vaccine -requires several injections -cannot cause disease -contains inactivated viruses -also known as Sulk vaccine OPV- -attenuated vaccine -stimulates IgA production -gives mucosal protection -provides herd immunity -may cause disease -also known as Sabin vaccine

Match each of the antibody classes with its description.

IgD-Involved in maturation of B lymphocytes and antibody responses, but function is largely uncharacterized. IgA-Most abundant class overall, but mainly found in mucosal secretions. Generally found as a dimer. IgM- First class produced in primary response. Forms a pentamer. Helps activate complement through the classical pathway. IgG-Main class found in blood. Only class that can cross the placenta. Found as a monomer. IgE-Binds via Fc region to mast cells/basophils. Involved in allergic responses and responses to parasites.

during the primary response, the first class of antibodies produced is

IgM

In some labs, samples containing suspected L. pneumophila are cultured on traditional BCYE medium containing L-cysteine, as well as BCYE medium lacking L-cysteine. How would L. pneumohila be identified in this situation?

In some labs, samples containing suspected L. pneumophila are cultured on traditional BCYE medium containing L-cysteine, as well as BCYE medium lacking L-cysteine. How would L. pneumohila be identified in this situation?

If you had to test 75 patients for antibodies to Bacillus anthraces (causative agent go anthrax), which immunoassay would you use?

Indirect ELISA

Which type of test would be most efficient for determining the approximate percentage of students in a class that had either been vaccinated against or infected with Bordetella pertussis (the bacterium that causes whooping cough)?

Indirect ELISA

Match the correct type of pattern recognition receptor (PRR) with the statement describing its function.

Interferon(s)- These proteins are often secreted when viral RNA is detected which signals neighboring cells to express antiviral proteins. RLRs-These proteins are found in the cytoplasm and can detect viral RNA TLRs-These receptors are found anchored in sentinel cells like macrophages and dendritic cells.They can bind to foreign structures like dsRNA, ssRNA and some bacterial DNA fragments NLRs-These proteins are found in the cytoplasm and can detect bacterial components

Match the types of cytoskeletal elements with their correct function

Intermediate filament- Mostly responsible for mechanical supports and helps the cell resist physical stress Actin filament- typically functions to allow the cell cytoplasm to move Microtubule- Involved in the movement of chromosomes during cell division

Why is Grams iodine added to the slide?

It forms complexes with the crystal violet, decreasing its solubility

Which of the following is TRUE about agar?

It has chemical and physical properties that makes it almost ideal for solidifying media

How does bacteriophage DNA get into the host cell?

It is injected

Match the Golden Age discoveries with the scientists who made them. Use the drop down bar to select the correct number.

LOUIS PASTEUR- Developed a microbial control technique for preserving food and liquid. JOSEPH LISTER- Published the first work on antiseptic surgery. ROBERT KOCH- Devised postulates for establishing causative relationship between a microbe and a disease PAUL ERLICH- Developed the first chemotherapeutic agent, for treating syphilis. WALTER AND FRANNY HESSE- Introduced agar-agar as a solidifying gel in culture media. CHRISTIAN GRAM- Developed staining method for differentiating between groups of bacteria.

Which statement about the endoplasmic reticulum and the Golgi apparatus is TRUE

Lipids and proteins synthesized by the endoplasmic reticulum are transported to the Golgi apparatus for modification and packaging into transport vesicles

What part of the body is affected with hepatitis?

Liver

Match the germicide with its use

Low-level disinfectant- used to treat floors, furniture, walls and so on high-level disinfectant-used to treat semi-critical instruments such as gastrointestinal endospores intermediate-level disinfectants-used to treat non-critical instruments such as stethoscopes sterilant-used to treat heat-sensitive critical instruments such as scalpels

After beta phage infects Corynebacterium diphtheriae and integrates its DNA into the host genome, the bacterium is capable of causing the disease diphtheria. Which term best describes this phenomenon?

Lysogenic conversion

Match the statement to the term that it most accurately describes to test your understanding of the elements of good microscopy

MAGNIFICATION- The apparent increase in size of an image RESOLUTION- the ability to distinguish between two separates structures that are very close to one another CONTRAST- ability to be distinguished from the surroundings

Place the labels into the correct columns for moist heat and dry heat

MOIST HEAT -pasteurizations -dentures proteins -more efficient -used to prevent food spoilage -used to sterilize microbial media -used to treat drinking water -used to sterilize surgical instruments -autoclaving -boiling DRY HEAT -incineration -burns cell components -less efficient -used to destroy medial waste -used to destroy animal carcasses -dry heat ovens -Bunsen burner

What would be a "good" argument against Spallanzani's experiment and in support of spontaneous generation?

Melting the flask neck closed kept the "vital forces" from entering and prevented spontaneous generation of life

Which of the following pairs is INCORRECT?

Memory cells- IgM

Does more or less antigen-containing fluid enter lymphatic vessels during inflammation?

More. During inflammation, junctions between endothelial cells of blood vessels loosen, allowing more fluid to leave the vessels.

What is the natural reservoir of the Ebola virus?

Most likely fruit bats or apes

The two 3-carbon molecules glucose is split into are converted through a series of steps into pyruvate. During these steps

NAD+ is converted to NADH

Place the descriptions into the correct columns to better understand the different types of immunity.

Natural active immunity- Results from an immune response in a person after exposure to an infectious agent -example: immunity that develops after a case of chickenpox Artificial active immunity -results from an immune response in a person after vaccination -example- receiving the MMRV vaccine Natural passive immunity -results with maternal antibodies are transferred to fetus during pregnancy or to infant by breast feeding -example- maternal anti-tetanus IgG antibodies crossing the placenta Artificial passive immunity-Results when antibodies in serum from another person or animal are injected to a person -examples: anti-rabies immunoglobulin injected after exposure to rabies virus

Your patient has ingested botulinum toxin, produced by the bacterium Clostridium botulinum. This toxin causes the neurological symptoms of the disease botulism. Your patient's immune system responds by generating antibodies. Which of the following antigen-antibody outcomes will be the most effective for your patient in this situation?

Neutralization

Please match each chemolithotrophic group with its source of energy.

Nitrifying bacteria- NH3 Hydrogen bacteria- H2 Sulfur bacteria-H2S Iron bacteria-Fe2+

Match each of the following items that may influence the selection of an antimicrobial procedure with its correct description/rationale.

Number of microorganisms-It takes longer to kill a large number of microbes than a small number Type of microbe-certain microbes are highly resistant to killing methods (e.g. endospores) Risk for infection- Items that may come into direct contact with body tissues are more likely to cause serious infections if contaminated Composition of the item- different materials respond differently to control measures. Some may even be destroyed by certain methods, preventing their use Environmental conditions- Dirt, grease, and bodily fluids in/on an area can interfere with control methods, as can temperature, pH, and even humidity levels.

Which of the following conditions would typically tigger sporulation for bacteria?

Nutrient depletion

You observe bacteria on the surface of a Petri dish of nutrient agar you left on the counter in your lab. You can be confident that your bacteria are NOT which of the following?

Obligate anaerobes

Spallanzani tried to disprove spontaneous generation by performing boiled broth experiments. In some experiments, he boiled broth and sealed the flasks. In others, he boiled broth, sealed the flasks, then cracked the seals. Choose which of the given statements are observations and which are conclusions, and drag and drop them into the appropriate column.

Observation- Broth in sealed flasks remains clear. Broth in cracked flasks gradually becomes cloudy Conclusion- Boiled broth in sealed flasks remains sterile. Broth only becomes contaminated if microbes can enter it. Life comes from previous life. Crackling a sealed flask allows microbes to enter the flasks

In prokaryotic DNA replication, which of the following is FALSE?

On one parent strand, the polymerase synthesizes DNA in the 5' to 3' direction, while on the other it synthesizes DNA in the 3' to 5' direction.

How does the bi-specific antibody in this case work?

One arm binds CD3 on a T cell while the other binds CD20 on a cancerous B cell, bringing them together for destruction by the T cel

In the late 1800's, Dr. William Coley, a cancer surgeon, noticed that patients who got an infection after their surgery actually did better than patients who did not. He developed Coley's Toxin, which was a mixture of dead bacteria (Streptococcus pyogenes and Serratia marcescens) that were used to treat cancer patients until the 1950s, when new treatments were developed. Now that you know that S. enterica has potential for fighting cancer partly by stimulating the patient's own immune system to recognize and destroy cancer cells more effectively, which of the statements about Coley's Toxin could be true?

One of the bacteria used in Coley's Toxin was a Gram-negative organism

Shown are results from membrane filtration of a water sample. Choose the statement that best describes this process

Only the microbes too large to make it through the filter are grown on the agar plate

What conclusion can be made from the summary?

Part of the preparedness plan includes ongoing education of health care providers about Zika virus

Which of the following are examples of antibiotics derived from fungi?

Penicillin and cephalosporin

Consider the figure. Select the CORRECT statement regarding penicillin and the bacterial cell wall

Penicillin will likely have a greater effect of the wall shown in anal A, which shows a Gram-positive cell wall

Select which of the following is NOT a matching pair.

Peyer's patches-skin

Following treatment with alum (aluminum sulfate), what can you conclude about Greenlake?

Phosphorus became a limiting agent

Anabaena is a genus of filamentous cyanobacteria commonly found in aquatic environments, where it harvests energy from sunlight and fixes both carbon dioxide and nitrogen. Knowing this, how would you classify Anabaena?

Photoautotroph

Greenlake is a small lake in Seattle, WA that sometimes experiences blooms of cyanobacteria, photosynthetic nitrogen-fixing bacteria that typically grow as filaments. These blooms are especially likely to occur during warm summer weather and result in the production of large quantities of biomass that then dies off and decomposes, leading to unpleasant odors. In addition to the aesthetic problems, some strains make toxins that can be dangerous to ingest, leading to the closing of the lake. Treatment of the water with alum (aluminum sulfate) to remove phosphorus from the water has helped to limit growth of cyanobacteria. How would you classify the cyanobacteria from Greenlake in terms of their carbon and energy sources?

Photoautotroph

how would you classify the cyanobacteria from Greenlake in terms of their carbon and energy sources?

Photoautotroph

Match each mechanism of resisting phage infection with its description.

Preventing phage attachment- Changing or covering up the molecules on the surface of the bacterium to which the phage particle bind CRISPR system- Insertion of small fragments of phage genome into host chromosome, giving the cell a "memory" of previous attempted infection and a way to recognize and destroy that foreign DNA in the future. Restriction-modification systems-Modifying self-DNA shortly after it's produced, followed by using restriction endonucleases to digest DNA that lacks modification.

If an infectious is composed only of amino acids, to which group does it belong?

Prions

Match the steps of Pasteur's swan-necked flask experiments with the scientific method process. Use the drop down bar to select the correct number to match each statement.

RECORDING DATA- Broth remains sterile unless flask is tilted, then growth occurs OBSERVATION- Sterile broth develops microbial growth when exposed to air EXPERIMENT- Construct swan-necked flasks allowing air but no microbes to enter QUESTION- Where do the microorganisms come from? HYPOTHESES- Microorganisms enter from the air CONCLUSION- Spontaneous generation is false. Life comes from pre-existing life

Which of the following is not involved in the initiation of translation?

RNA polymerase

The symptoms of botulism are a result of nerve damage caused by botulinum toxin. Given this information, select which of the following you think would be a treatment for affected people.

Respiratory support and antitoxin (neutralizes toxin)

You are a lab technician and you isolate several copies of a molecule from the cells you are working on. The molecules contain uracil, are small, and most are bound to amino acids. What are the molecules?

Ribosomal RNA

Which of the following types of repair does not require the standard DNA polymerase with proofreading capability?

SOS repair

Classify the given microbes and infectious agents into "sensitive" or "resistant" with regards to effect of antimicrobial procedures.

Sensitive- Bacillus vegatative cells/ HIV (enveloped)/ Escherichia species Resistant- Bacillus endospores/ Poliovirus (non-enveloped)/ Prion/ Giardia cysts/Mycobacteria species/ Pseudomonas species

Which term is used to describe the region of a protein that directs the secretion machinery to move the protein across a cytoplasmic membrane?

Signal sequence

Which of the following about simple and differential staining is CORRECT?

Simple stains use a single color while a differential stain uses more than one color to highlight differences between certain groups of cells

Which feature of the cytoplasmic membrane allows for the proton motif force?

Specialized proteins embedded in the cell membrane allow for protons to cross it and generate ATP

John Needham designed an experiment in which he boiled some brother and then corked the flask it was in, thereby sealing the flask. After a few days, he noticed that the broth had microbes in it! When did people conclude from Needham's experiment?

Spontaneous generation of small things like microbes still occurs

A skin swab yields cells that appear as clusters of round cells under the light microscope. Given this information, it is possible that the organism is

Staphylococcus aureus OR Staphylococcus epidermis

Which of the following was NOT included as a standard laboratory microbe in this research?

Staphylococcus epidermidis

Which of these is base-paired correctly?

T-A

The receptors found on the T cell in the figure are

T-cell receptors and CD8 proteins

Which of the following pattern recognition receptors is/are anchored in the host cell membrane?

TLRs and CLRs

Which of the following explains why the woman in this case developed the signs and symptoms of CDI, an intestinal infection?

The antibiotic harmed her intestinal normal microbiota, allowing C. difficile to flourish (thrive)

You inoculate a flask containing a complex medium with a culture of bacteria and use a spectrophotometer to measure the absorbance of the culture to detect growth. Initial measurements show a modest turbidity (cloudiness) that remains unchanged for the first few hours, followed by a steady increase for the rest of the day. Why was there this delay in growth following inoculation?

The bacteria were actively expressing genes and synthesizing enzymes in order to grow in their new environment.

What would be the consequence of a transposon inserting into the site shown by the red arrow?

The bacterium would likely become sensitive to tetracycline

In direct selection methods used to identify possible carcinogens (example: Ames testing), what does it mean when a chemical can cause a bacterium to develop resistance to some environmental condition?

The chemical is a mutagen

What feature of the eukaryotic membrane differentiates it the most from the prokaryotic cytoplasmic membrane?

The composition of the phospholipid layer facing the outside of the cell is significantly different compared to the lipid layer facing the cytoplasm

To which part of a DNA molecule are nucleotides added?

The hydroxyl group on the 3' end of the molecule

Choose the statement that best describes the concept behind the enrichment culture method

The liquid culture enhances growth of only certain microbes, so their numbers increase in proportion with each transfer

What is oxidation

The loss of electrons from a molecule

The safe temperature ranges for the storage of foods are determined by

The low temperature at which microbes stop multiplying and the high temperature at which they die

Which of the following describes stationary phase of a growth curve?

The number of cells dividing equals the number dying

You are analyzing a bacterial genome. You find that the G-C content is 60%. However, in one part of the genome, the G-C content is 37%. What can you conclude?

The organism has a genomic island

When setting up the reaction in tube 1, you measure the rate of product (brown pigment) formation upon adding the catechol substrate. If you set up another tube but instead add twice the amount of substrate, what do you think would be the effect on the rate of product (brown pigment) formation compared to the first test tube? Assume that the enzyme is not saturated with substrate.

The rate of the second tube would be faster than that of the first tube

What is the significance of this research

The researchers have identified a molecule that may be used in a vaccine to protect against zika virus disease

What is the significance of this research?

The researches suggest that drugs that destroy the outer membrane of Gram-negative cells could provide a novel therapy approach

Delivering siRNA to the exact tissue site it is needed by means of hydrogels has been somewhat successful. What is the main problem with this approach?

The siRNA diffuses quick out of the gel, so does not remain at the site for long enough to work well

Which is the best definition of generation time?

The time it takes for the number of cells in a. population to double

Two bacterial genes are transducer simultaneously. What does this suggest about the location of the two gene relative to each other

The two genes must be close together on the bacterial chromosome

Which of the following is FALSE about transposons?

They are capable of moving independently from one cell to another cell

The report notes that of the positively confirmed measles cases in this report, 62 patients were unvaccinated, including 50 who were 12 months or older in age. Why do the authors point out the age of these children?

They are informing us that these children were old enough to have received at least one dose of the MMR vaccine

Which of the following is NOT given as a reason that zebrafish are used for testing biologically active compounds?

They are invertebrates and have no nerves

What happens to the protons received from NADH in bacteria?

They are transported across the cytoplasmic membrane, setting up a proton motive force

Which of the following are TRUE regarding trace elements?

They include zinc, copper and manganese AND they may be needed for enzyme function

What did the researchers do in this report that solved the problem of siRNA diffusing out of hydrogel too fast?

They tethered the siRNA to the hydrogel with a link that is gradually degraded in the presence of water, slowing the RNA release from the gel.

How did the children in this study get measles?

They were unvaccinated and caught it during a measles outbreak.

Match the chemical mutagens with their descriptions.

Transposons- randomly insert into DNA Alkylating agents-Add CH3 and others to nucelobases Intercalating agents- Insert between base pairs Base analogs-Used in place of normal nucleobases

Please classify the following as either triumphs or challenges by moving them into the appropriate columns

Triumph- Eradication of smallpox Measles, mumps, rubella, varicella vaccine (MMRV) Control of rodent populations harboring the bacteria causing the plague Challenge- HIV/AIDS Hantavirus pulmonary syndrome COVID-19

A bacterium that can be seen without a microscope exists

True

A helper T cell must be activated before it can stimulate a B cell to produce antibody.

True

Antigen fragments are presented at the surface of macrophages along with self proteins

True

Bacteria may be involved in both the production or food and in its decay

True

Both antigen-presenting cells and B cells have class II MHC receptors on their surface.

True

Both enveloped and non-enveloped (naked) viruses can enter a cell by endocytosis

True

Botulinum toxin is a protein. Heating the canned potatoes before using them in the salad could have prevented this botulism outbreak.

True

Improper base-pairing during DNA replication causes a pause in chain elongation.

True

In the name Escherichia coli K12, K12 refers to the strain

True

Nadim is unlikely to have received a vaccine against pathogen A

True

Plastoquinone is the primary electron acceptor for electrons leaving photosystem II.

True

Replication, transcription and translation take place in the bacterial cytoplasm.

True

Some of the patients at the dialysis facility were already infected with HCV prior to the outbreak described in the case study

True

The Calvin cycle fixes carbon dioxide into organic molecules

True

The donor cell DNA is integrated into the recipient cells's DNA by homologous recombination

True

The energy captured in the phosphorylation of ADP to ATP comes from the proton motive force created in respiration.

True

The fecal matter used in a transplant must be carefully screened before use.

True

The government agencies that regulate germicidal chemicals are the Food and Drug Administration (FDA) and the Environmental Protection Agency (EPA).

True

The resolving power of electron microscopes is much better than the resolving power of light microscopes because the wavelength of the electron beam is shorter than the wavelength of visible light.

True

There is no link between the MMR vaccine and autism

True

What is a synonym for the word "employed" which we see in this sentence: Pasteur studied the relationship between yeast and alcohol production using a strategy commonly employed by scientists today?

Used

Place the statements about viroids and prions into the correct columns. Not all statements are used.

Viroids -composed of nuceleotides -cause disease in plants -enter through wounds -cadang-cadang Prions -composed of amino acids -cause disease in animals -inherited or consumed -Creutzfeldt-Jacob disease

What do the researchers in this article propose may be used to create a Zika virus disease vaccine?

Virus envelope containing the E protein

What conclusion can you make from the data presented?

Washing your hands with water removes some bacteria, but adding soap is more effective.

Phosphate is typically a limiting nutrient in waterways. Phosphate was historically widely used in detergents, but because wastewater treatment plants do not fully remove phosphate before discharging their treated water, it has been mostly removed from these detergents in order to protect our waterways. Some complain that modern detergents do not clean as well following this change. Predict what would happen if phosphate was returned to detergents.

We would experience blooms of cyanobacteria and algae in our waterways.

Which type of test would be most accurate for determine if an individual had antibodies against a specific protein subunit of cholera toxin

Western blot

Why did the researchers have to introduce a new metabolic pathway into the E. coli they were using to synthesize muconic acid?

When the bacteria use the available carbon sources to synthesize muconic acid, they stop multiplying as well and the population weakens

Why is the process of gene rearrangement used in creating antibodies and T-cell receptors (TCRs) so important?

Without it, we would need a single gene for every antibody and TCR required to mount all the possible responses needed during our lives.

Categorize the given chemicals according to their uses.

Wounds- halogens/ metals Medical Instruments-Aldehydes/ ethylene oxide/ peroxygens Soaps- Biguanides/phenolics

You take a swab sample from a patient, stain it and culture it. You observe spherical bacteria in the staining preparation. The organism grows equally well throughout a tube of thioglycolate culture medium. It does not produce catalase. From this you can conclude it is likely

a Streptococcus species

Generalized transduction occurs when

a bacteriophage packages a piece of bacterial DNA during replication

Generalized transduction occurs when

a bacteriophage packages a piece of bacterial DNA during replication.

People who have compromised first-line defenses are susceptible to opportunistic pathogens. Which situation would be an example of a compromised first-line defense?

a burn patient who has lost extensive areas of the skin

Negative staining is commonly used to determine if bacterial cells have

a capsule

Hfr refers to

a cell in which the F plasmid has been integrated into the cell chromosome

Which of the following is an example of artificial active immunity

a child who has been inoculated with the chickenpox vaccine

An antigen-presenting cell presents antigen to a helper T cell on its surface using ______.

a class II MHC molecule

During maturation or formation of phage particles

a few phage heads may surround fragments of host bacterial DNA

During maturation or formation of phage particles,

a few phage heads may surround fragments of host bacterial DNA

A ingle species of bacteria grows best at

a modest range around an optimum temperature

The F pilus is

a protein appendage that attaches the two cell together

An open reading frame or a possible protein-encoding region of prokaryotic DNA is

a region of DNA that begins with a start codon (ATG) and ends with a start codon

Which of the following is required to maintain a lysogenic state?

a repressor protein

In the absence of lactose,

a repressor protein binds to the operator

The electron carrier proteins in the electron transport chain shuttle electron to

a terminal electron acceptor

The signs and symptoms of the disease tetanus include muscle spasms and paralysis. The disease is caused by Clostridium tetani, a bacterium that produces a toxin called tetanospasmin. Considering these facts, a protective vaccine against tetanus would contain

a toxoid

What is apoptosis

a type of programmed cell death

Plasmids are

able to replicate independently of the chromosome

Which of the following is required for prion replication?

abnormal prion protein

When outbreaks occur, the attack rate can be calculated—this describes the proportion (percentage) of people becoming ill in a population after exposure to an infectious agent. Attack rate is calculated as the total number of cases divided by the total exposed population. What is the attack rate in this case?

about 1.4%

Which of the following is NOT a function of inflammation?

activate the complement system

Phagocytes can be enhanced by immunological mediators such as

activated complemented proteins

phagocytosis can be enhanced by immunological mediators such as _______

activated complemented proteins

One of the most important jobs of dendritic cells is

activation of T cells by breakdown of whole antigens and presentation of antigenic epitopes on MHC molecules

In the absence of lactose, the lac repressor is

active and can bind to the operator

Global radiation of poliomyelitis will ultimately depend on

administering IPV followed later by a booster containing OPV

In a quantal assay, animal viruses are quantified by

administering several dilutions of a virus preparation to a number of animals, cells, or chick embryos, then determining the dilution that infected/killed 50% of the group.

Examples of advantageous genes that can be transferred by transduction are genes for

all of these - sugar fermentation -toxin production -drug resistance -only drug resistance and toxin production

Clusters of differentiation (CD) molecules are important because they

allow us to differentiate between cells that may look identical by microscopy.

The plasmid is mobilized for transfer when

an endonuclease cleaves it at the origin of the transfer

The best parts of the bacteriophage are

an icosahedral head, tail, tail pins, and fibers

The basic part of the bacteriophage are

an isohedral head, tail, tail pins, and fibers

A culture of E. coli is growing on glucose salts agar (GSA), a chemically defined medium that contains glucose as its sole carbon source. E. coli utilizes the glucose for both its energy and carbon needs. During metabolism, it uses precursor metabolites of its central metabolic pathways and ATP to build up the biological macromolecules needed to make cell components. These biosynthetic reactions are best described as ______.

anabolism

Which of the following antimicrobial substances are not part of our body's first line of defense?

antibodies

All of the following events can occur after complement activation except

antibody production

Helper T cells interact with target cells by recognizing

antigen-MHC protein complexes

A helper T cell becomes activated by a(n)

antigen-presenting cells

The two strands of the DNA molecules are ________

antiparallel

Viral spikes

attach specifically to host cell receptors

The antigens being tested for indirect agglutination reactions are

attached to whole cells

The stage of T4 replication that involves interaction between the protein fibers on the phage and receptors on the bacterial cell wall is the

attachment stage

Please sort the statement about attenuated and inactivated vaccines into the appropriate columns to show you understanding of vaccine characteristics

attenuated vaccines -pathogen may be revert to virulence -contain live, weakened pathogen -elicit long-;acting immunity -pathogen multiplies in the vaccine recipient -may cause disease immunocompromised -usually not given to pregnant women -require refrigeration to keep activity -example: MMRV vaccine Inactivated vaccines -pathogen never reverts to virulence -elicit weaker immune response -pathogen does not replicate in recipient -booster doses required to maintain immunity -safe for reagent women -pose no risk to immunocompromised -example: Hepatitis A vaccine -contain adjuvants for increased immunity

A virus that infects bacterial cells is called a _____

bacteriophage

Viruses that infect bacterial cells are called ______.

bacteriophages

A newly synthesized protein that contains a signal. sequence will likely

be secreted from the cell that made it

Why are dialysis patients particularly susceptible to blood-born infections

because their blood is processed in a dialysis machine that could be the source of infection

The presence of microbes in food can be

beneficial, harmful, or neutral

Identify the types of microorganism based on their optimal growth temperatures. Not all labels are used

blue- psychrophile green- psychrotroph purple- mesophile orange-thermophile red- hyperthermophile

When the defective phage enters a new bacterial cell

both phage DNA and bacterial DNA integrate into the chromosome of the new cell host.

Early in glycolysis, two phosphates are added to the glucose molecule. These phosphates come from

breaking down ATP

After entry of the bacteriophage into the host cell, a phage enzyme

breaks the host DNA into fragments

After entry of the bacteriophage into the host cell, a phage enzyme

breaks the host DNA into fragments.

how are microbes killed and digested in the phagolyosome?

by hydrolytic enzymes

The coenzymes NADH is generated by

by oxidation reactions in glycolysis and the Krebs cycle

If conditions are favorable, the generation time of bacteria

can be as short as 30 minutes

A positive (+) strand of RNA

can directly act as mRNA

When the bacteriophage transfers bacterial DNA into a recipient bacterial cell, this DNA

can integrate into the chromosome

When the bacteriophage transfers bacterial DNA into recipient bacterial cell, that DNA

can integrate into the chromosome

Expression of viral oncogenes in infected animal cells

can mimic proto-oncogenes, causing imbalance in cell cycle control towards unchecked proliferation, leading to tumor formation.

A candle jar is typically used to grow

capnophiles

A culture of bacteria is breaking down sugars to yield energy. This is best described as

catabolism

T-dependent antigens

characteristically have a protein component

The synthesis of ATP via ATP synthase, driven by a proton motive force, is called ______.

chemiosmosis

Match the following cytokines with their general functions

chemokine- these cytokines are important in the chemotaxis of immune cells colony-stimulating factors- these cytokines are important in the multiplication and differentiation of leukocytes interferons- thee cytokines are important in the control of virally-infected cells interleukins- these cytokines are produces by leukocytes and are important in both innate and adaptive immunity tumor necrosis factor- these cytokines are important as triggers for inflammation and apoptosis

2. The four classic signs and symptoms of inflammation include all the following EXCEPT

chills

Horizontal gene transfer can occur via

conjugation

Recipients of the Sabin polio vaccine sometimes develop polio. Based on this information you can assume that the vaccine

contains attenuated pathogen

UV light and other non-ionizing radiation damage DNA molecules by

creating thymine dimers between adjacent thymine nucleobases in the DNA chain

Helper T cells secrete ______ to stimulate the proliferation of B cells.

cytokines

Complement factors C5b+C6+C7+C8 make up a membrane attack complex that results in

cytolysis

Gram-positive bacteria retain the crystal violet-iodine complexes because the ethanol/acetone

dehydrates the thick peptidoglycan cell wall, making it impermeable

Moist heat primarily destroys microbes by

denaturing their proteins

The movement of dissolved solutes from a region of higher concentration to a lower concentration is called

diffusion

Chlorine has traditionally been used to disinfect water, preventing the spread of waterborne illnesses. However, chlorine (and other disinfectants) can react with naturally occurring water chemicals, forming ______, which can have long-term health risks.

disinfection by-products (DBPs)

Which of the following statements about normal microbiota is FALSE?

disruption of the normal microbiota has little effect on the host

There are three different gene segments that come together to encode the variable region of an antibody heavy chain molecule. When encoding the light chain, only two different gene segments are joined. The gene segment that is used in encoding the heavy chain but not the light chain is the ______ segment.

diversity

During the development of both B and T cells, a process called negative selection occurs. This is necessary because it helps ensure that the cells

do not recognize "self" molecules.

Which of the following best describes the vertical gene transfer?

duplicating the entire genome and passing a copy to a daughter cell

Match the words/phrases with their correct definitions in the context of this article.

emerging disease- a disease that is new or increasing in incidence Plasma-Fluid part of blood counting proteins but lacking blood cells and platelets Natural reservoir- plant, animal, soil or other habitat in which a pathogen is lives and multiples Reconvalescent donors-Blood/plasma donors who have recovered from EBOD. hemorrhaging-extreme bleeding stringent- very strict or severe

Binding of an activator to an activator binding site on DNA

enhances the ability of RNA polymerase to bind to the promoter site

phagocytes are attracted by all of the following EXCEPT

enzymes released by lysosomes

RNA interference (RNAi) is a mechanism by which

eukaryotic cells destroy RNA transcripts in a selective and specific manner to control gene expression

The phages T4 (lytic) and lambda (temperate) share all of the following characteristics EXCEPT

existing as a prophage

in phagocytosis, the digest contents are eliminated by

exocytosis

After conjugation of an Hfr cell and an F- cell, the entire genome of the Hfr cell is usually transferred to the recipient cell.

false

Complement factors are named in the order in which they function.

false

Generalized transduction is so called because specific bacterial genes are transferred during this process

false

Once a phage becomes lysogenic, it will remain lysogenic and never be lytic again.

false

The patient in this case was successfully cured of his C. immitis infection after prolonged treatment with fluconazole

false

A staining technique that uses immunofluorescent dyes or antibodies will typically use which of the following types of microscopes

fluorescence microscope

Examine the image and determine which serological method is used

fluorescent antibody test

How do chemolithotrophs acquire energy?

from inorganic compounds

In eukaryotic cells undergoing respirations, protons are pumped

from the mitochondrial matrix to the intermembrane space.

Helper T cells

function in both cell-mediated and humoral immunity

The cell wall of Gram-negative organism

has a thin peptidoglycan layer AND is characterized by an outer membrane containing LPS.

An infant with microcephaly

has smaller than normal skull and brain

Your patient has an acute lymphocytic leukemia and is receiving the medication blinatumomab, a bi-specific antibody. This antibody

has two antigen-binding sites: one binds a protein on T cells and the other binds to a protein on cancerous B cells, connecting the two cells and increasing the chances that the T cell kills the B cell.

F+ cells

have a plasmid and are donors in conjugation

Early in the process of DNA replication, the enzyme ______ separates the two strands.

helices

The proofreading function of DNA polymerase reduces the error rate from about one in a million base pairs to about one in a ______ base pairs.

hundred million

The two strands of DNA are joined to each other or held together by

hydrogen bonding

These dimers weaken ____ between bases

hydrogen bonds

Diversity of antibodies is increased by ______, which leads to deletions/insertions of nucleotides between joined gene segments.

imprecise joining

Plasmid DNA is transferred

in single-stranded form

A fundamental aspect of gene regulation lies in the ______ of mRNA molecules. Because of this trait, these molecules won't remain in the cell long after transcription has been turned off by the cell, regulating gene expression.

instability

You discover a new microbe that contains peptidoglycan. Based on this information, the most logical conclusion you can draw about the organism is that it

is a bacterium

After producing the IFN, the cell shown in the figure

is destroyed as a result of the virus infection

Unlike a disinfectant, an antiseptic

is non-toxic enough to be used on human skin

The negative (-) sense strand of RNA

is used to synthesize more (+) strands

Which of the following statements about complement protein C1 is FALSE?

it cleaves C3 into C3a and C3b

boiling is not a reliable method for sterilization because

it does not destroy heat-resistant endospores

Which of the following describes the action of RNAi?

it interferes with translation by blocking target mRNA

In transduction, bacterial DNA is transferred to a new cell when

it is injected by the virus

In transaction, bacterial DNA is transferred to a new cell when

it is injected by the virus carrying bacterial DNA

Which role does histamine play during inflammation?

it leads to vasodilation

When a bacterium is grow on glucose only,

it must synthesize all the amino acids it needs

In an inducible operon, when a substrate or inducer is present,

it reacts with the repressor and inactivates it

Which of the following is NOT an antimicrobial substance?

keratin

After glycolysis, pyruvate can be converted into ______ under anaerobic conditions.

lactic acid

Pasteur's swan-necked flask experiments resolved the criticism that without "vital force" microorganisms cannot grow, by

leaving the flasks open to the air that "vital force" was present.

During which phase of growth do researchers measure the generation time of culture of bacteria?

log phase

Which of the following describes a latent viral infection?

long periods of time with essentially zero viral replication, punctuated by outbreaks of of active replication are largely non-infectious between outbreak periods.

A _____ contains hydrolytic enzymes to digest foreign bacteria

lysosome

The microbe is digested within the phagocyte by enzymes delivered by a _____

lysosome

the microbe is digested within the phagocyte by enzymes delivered by a

lysosome

Bacteriophages involved in generalized transduction are ______ phages

lytic

Viral cycles that end in release of the new phages and immediate destruction of the host bacterial cell are referred to as ______.

lytic

Which of the following codes for a protein?

mRNA

Which of the following statements about phagocytosis is FALSE?

macrophages die after phagocytosis bacteria, but neutrophils survive

B cells differentiate into plasma cells and ______.

memory cells

Which of the following is an example of a growth factor?

methionine

Match each type of radiation with its description

microwaves-Doesn't affect microorganisms directly, but can generate heat in fluids which can indirectly kill microbes. ionizing radiation-High energy radiation that directly destroys DNA and damages cytoplasmic membranes. It can also cause indirect damage by producing reactive oxygen species (ROS). Ultraviolet radiation-Not very penetrating radiation. Easily stopped by interfering materials. Works by producing thymine dimers in DNA strands. Most effective at close range and with long duration of exposure.

Match the listen objects and compounds with the appropriate method used to destroy microbes and viruses on/in them

moist heat-culture media/milk dry heat-medical waste/inoculating loop/animal carcasses radiation-meat products/heat-sensitive medications

Which of the following statements about bacteria is FALSE

most bacteria have been grown in culture and characterized

A medical technician examines a Gram stain of purulent discharge (pus) from a patient with an active infection. Which predominant host cell type will the technician most likely see?

neutrophils

Assign the statements about macrophages and neutrophils into the correct columns.

neutrophils -short-lived, lasting only a few days -release destructive enzymes and antimicrobial peptides -fit cells recruited from bloodstream to sit of damage -die after releasing their cell-damaging contents macrophages -long-lived, lasting weeks or months -act as sentinels, alerting other immune cells to microbial invaders -may become part of concentrated groups called granulomas -continually regenerate their lysosomes, maintaining killing power

Extravasation, also known as diapedesis or transmigration, occurs when

neutrophils squeeze through the blood vessel wall

If gene X codes for an F pilus and transposition occurs, then the bacterium containing the plasmid would

no longer be able to conjugate

Please match each type of mutation with its appropriate description.

nonsense mutation- a mutation that changes a codon that specifies an amino acid to a stop codon, resulting premature termination of polypeptide synthesis missense mutation- a mutation that results in changing a codon such that a different amino acid is specified silent mutation- mutation that changes a codon into a different codon, but both codons specify the same amino acid; this causes no change in the resulting polypeptide frameshift mutation- a mutation resulting from an insertion or deletion of bases that causes change in the reading Fram of the mRNA

Which of the following pairs is NOT correctly matched?

nonsense mutation-incorrect amino acid

A recombinant organism is

one that contains genes from another organism

in the process of specialized transduction

only a few specific genes from one bacterial cell are transferred to the second bacterial cell by a phage.

Which statement about biofilms is INCORRECT

only bacteria have the ability to form biofilms

In specialized transduction

only bacterial genes near the site of integration of the phage DNA can be transduced.

Bacteriophages absorb or attach

only to members of the same bacterial species

The specific point on the DNA molecule where replication begins is the

origin of replication

What was the likely source(s) of infection at the dialysis center?

other patients

Cells obtain _____ food molecules such as glucose

oxidizing

To isolate penicillin-resistant mutants, the scientist must inoculate the parent population on plates containing ______; this approach is ______ selection.

penicillin; direct

The bond connecting amino acids is a ____ bond

peptide

After host cell DNA is broken down by a viral enzyme

phage DNA is replicated and phage coat proteins are produced

After host cell DNA is broken down by a viral enzyme,

phage DNA is replicated and phage coat proteins are produced

After being engulfed, a microbe is found within a

phagosome

after being engulfed, a microbe is found within a ______

phagosome

distinguish between genotype and phenotype

phenotype-The organisms observable characteristics. For example, presence of a flagellum Genotype- The generic makeup of the organism-in other words, the DNA sequence

The three basic parts of a DNA nucleotide are

phosphate, deoxyribose sugar, nitrogenous base

Haemophilus influenzae is a Gram-negative coccobacillus. If you looked at a Gram-stained culture using a light microscope, you would expect to see

pink, very short rods

Antibodies are produced by

plasma cells

The antibody-producing progeny of an activated B cell are called ______

plasma cells

A difference between transferring plasmid and DNA fragments between bacterial cells is

plasmid can replicate independently

A difference between plasmids and fragments of DNA that have been transferred between cells is

plasmids can replicate independently

You tell your friend you think she may actually have pneumonia caused by Mycoplasma pneumoniae, a ______ organism that lacks a ______.

pleomorphic; peptidoglycan cell wall

In the Ouchterlony test (such as the one shown here), the white lines form because of

precipitation of antigen-antibody complexes

The main purpose of cellular respiration is to

produce energy

Categorize the descriptions of mRNA as being true for either prokaryotes or eukaryotes.

prokaryotes- polycistronic messages/ribosomes-binding site eukaryotes- introns/5' cap/polyadenylated

The Hib vaccine (Hib = Haemophilus influenza type b) is specially constructed so that an infant's immune system will mount an immune response against the bacterium's capsule. Based on this information, the vaccine is likely a

protin-polysccharide conjugate

The enzyme ATP synthase uses energy from ______ to make ATP

protons re-entering the cell

If you viewed the slide microscopically after the ethanol/acetone step, gram-positive cells would appear ____, while Gram-negative cells would appear ____

purple; colorless

If you viewed the slide microscopically after the crystal violet step, Gram-positive cells would appear _____ in color while Gram-negative cells would appear _____ in color

purple; purple

What type of programmed cell death also triggers an inflammatory response, recruiting various components of the immune system to the region?

pyroptosis

Toll-like receptors (TLRs) bind molecules on pathogens. This is helpful to the immune response because TLRs

recognize broad categories of molecules that should not be in our system, as we don't have these molecules on our own cells.

All of the following cells have class II MHC receptors on their surface EXCEPT

red blood cells

Phage DNA encodes for the proteins of the viral capsid and

regulator proteins that direct the production and assembly of the capsid proteins

Which of the following is a function of the mucociliary escalator?

removes microbes from the respiratory tract

DNA polymerase

requires a template for the synthesis of DNA

If you find that a particular plasmid has an R factor, the bacteria that has it will be

resistant to certain antibiotics

Protein synthesis occurs on the _____

ribosomes

Which process involves more rapid synthesis and greatly increase titer of antigen when immune system is subsequently exposed to the same antigen?

secondary response

Transposons are

segments of DNA

to determine antibody titer, you will need

serial dilutions of the patients serum

During the electron transport chain in bacteria, protons are

shuttles to the outside of the cell membrane

During conjugation, the donor chromosome is transferred as

single-standard DNA

The antigens being tested for in precipitation reactions are

soluble and not bound to cell surfaces

The F pilus binds to

specific receptors on the cell wall of the recipient

The term used to describe a cluster of spherical bacteria is

staphylococci

n translation, the codon at which the process begins is called the ______ codon, while the codon at which the process ends is called the ______ codon.

start; stop

Match the phase of the bacterial growth curve with its description. Not all labels are used

stationary phase- with nutrients depleted, total number of viable cells remains constant, with some dying while others multiply exponential/log phase- cells are actively growing, doubling the population with each generation lag phase- cells are not dividing but are synthesized enzymes required for growth death phase- due to nutrient depletion and waste accumulation, cells being to die at an exponential rate

The simplest technique for isolating bacteria is referred to as the

streak-plate method

The environmental factor that influences bacterial growth the most is

temperature

If a TC encountered a TH cell infected with a virus,

the Tc cell would induce apoptosis in the TH cell

In a capsule stain,

the background stains dark, so that the capsule is visible

In the electron transport chain, protons are pumped across the cell membrane. This results in

the formation of a proton motive force

In viral entry by endocytosis

the host cell's cytoplasmic membrane surrounds the whole vision and forms a vesicle

All of the following are characteristics of eukaryotic gene expression EXCEPT

the mRNA is often polycistonic

Thioglycolate medium is used to determine the oxygen requirements of a microorganism. You inoculate a tube of this medium with a bacterium and observe dense growth at the bottom of the tube. From this you can conclude that

the organism is an obligate anaerobe

When labeled rabbit anti-human antibody is used in an ELISA, the antibody binds directly to

the protein of interest

After the conjugation of an Hfr cell with an F- cell,

the recipient remains F-.

When an amino acid such as arginine binds to a repressor,

the repressor bunds to the operator site

When filtering a liquid, it is a bad idea to use a membrane with a pore size smaller than necessary because

the smaller the pore size, the slower the filtration process, so you would be wasting time

Two different mechanisms for copying the DNA strands are used because

the strands are orientated in opposite directions

In aerobic respiration, oxygen acts as

the terminal electron acceptor

these dimers are repaired by

then enzyme DNA photolyase AND exposure to light

The main advantage for bacteria that have the ability to carry out conjugation and other forms of genetic exchange is that

they become genetically diverse

What is the function of selectins

they promote sticking of neutrophils to the inner vessel wall

Why does M. tuberculosis manipulate the macrophage that engulfs it?

to avoid destruction by the macrophage

Metagenomics is the analysis of

total microbial genomes in an environment

The type of food-borne infection known as an intoxication is caused by

toxins produced by microbes as they grow in the food

All of the following are matching pairs EXCEPT

toxoid-passive immunity

Most solutes pass through the cytoplasmic membrane via

transport proteins

Complement factor C3b coats a bacterium and binds to C3b receptors on phagocytes, making the bacterium more susceptible to being phagocytized

true

If a bacterium could escape from a phagosome, it would be able to resist digestion by that phagocyte

true

It is possible for one host to be resistant to infection by a pathogen that can normally cause disease in a different host.

true

Margination occurs when neutrophils stick to the lining of the endothelium.

true

Microbes will only grow until the least represented (limiting) nutrient is used up

true

Sometimes a piece of bacterial DNA near the specific site of insertion stays attached to the phage DNA, and a piece of phage DNA remains behind.

true

The lambda phage DNA always integrates into the host DNA in the same specific site.

true

Using parallel pathway metabolic engineering, the scientists in this article were able to produce E. coli that used one metabolic pathway to produce metabolites for growth, and a different metabolic pathway to produce a target compound.

true

removal of the capsid to release the virus nucleic acid into the host cytoplasm is called

uncoating

HIV disease progression can be monitored using fluorescence-activated cell sorting by

using a fluorescent dye to label anti-CD4 antibody, and counting the number of CD4+ T cells in a patient's blood sample.

The symptoms of inflammation are mostly due to ______

vasodilation

Please choose the statement that best describes the role of viral surface proteins or spikes

viral spikes provide means of attachment to host cell surface

You discover an agent that multiples in plant cells and is composed of RNA but nothing else. This agent would be a

viroid

The electrons excited by photons of light are replaced by electrons from ______ in photosystem II, and by electrons from ______ in photosystem I.

water; photosystem II

Opsonization is

when complement enhances phagocytosis of a bacterium