Microbiology

When controlling microbial growth cold is considered

Bacteriostatic

The ability to utilize glucose is an example of this identification method

Biochemical Tests

Lockjaw is a disease transmitted by organisms in the genus __________

Clostridium

You have 2 colonies. Both grow on complete media. When you plate the 2 colonies on different media (minimal medium with glucose or minimal medium with glucose and leucine) you see the following differences: Colony A can grow on both minimal media, but Colony B can only grow on the minimal medium with glucose if leucine is added. What is the likely genotype of colony B

Colony B is leu-

If the following DNA sequence is replicated, what the bases that will be added to complete the sequence: 5' AACGTC 3' TTGCAGATATTCG 5'

TATAAGC

The term facultative anaerobe refers to an organism that a. Is killed by oxygen b. oxygen or grows without oxygen c. Doesn't use oxygen but tolerates it d. Prefers to grow without oxygen e. Requires less oxygen than is present in air

Uses oxygen or grows without oxygen

Which of the following would be the first step in biosynthesis of a virus with a (-) strand of RNA? a. Synthesis of RNA from an RNA template b. Translation of mRNA c. Synthesis of DNA from an RNA template d. Synthesis of RNA from a DNA template e. Transcription of mRNA from DNA

a. Synthesis of RNA from an RNA template

Which of the following is NOT a chemical component of a bacterial cell wall? a. cellulose b. peptidoglycan c. N-acetylmuramic acid d. peptide chains e. teichoic acids

a. cellulose

Vibrio cholera is a. produces an exotoxin b. a nonproteobacteria c. found on land d. is a respiratory pathogen

a. produces an exotoxin

Which compound provides the electrons at the start of the electron transport chain? a. H2O b. NADH c. O2 d. ATP e. FAD

b. NADH

The mode of action of erythromycin is a. Injury to the cytoplasmic membrane b. Inhibition of folic acid synthesis c. Inhibition of protein synthesis d. Inhibition of RNA synthesis e. Inhibition of DNA synthesis

c. Inhibition of protein synthesis

Which combination can never be part of a virus structure? a. RNA-helical b. RNA-helical- envelope c. RNA-envelope d. RNA-icosahedral-envelope e. DNA-helica

c. RNA-envelope

The "Enterics" are a. aerobes b. nonmotile c. found in the respiratory tract of humans d. gram-positive rods e. able to use fimbriae for attachment

e. able to use fimbriae for attachment

For the following questions 1-4, decide if they are describing A. gram positive cell wall B. gram negative cell wall C. both D. none Cell wall that can be toxic to humans ____________ Cell wall that can protect against osmotic lysis? ____________ Cell wall that contains teichoic acids? ____________ Cell wall that contains long polymers of glucose ____________

1 = b 2 = c 3 = a 4 = d

For each of the phrases (In questions 1-4), indicate the type of metabolism referred to using the following choices: A. Anabolism B. Catabolism C. Both (amphibolic) 1. Breaks a large molecule into smaller ones ____________ 2. Requires energy ____________ 3. The Krebs cycle ____________ 4. Protein synthesis ____________

1 = b 2= a 3 = c 4 = a

Match the structure with the function (answers may be used more than once or not at all) Possible Functions a) energy reserves b) reproduction c) phosphate reserves d) destroy hydrogen peroxide e) digestive enzyme storage STRUCTURE FUNCTION 1) Pili 2) Magnetosome 3) Sulfur granules

1) = b 2) = d 3) = a

Multiple Matching. Fill in the blanks with the letter of the word below that apply. (Answers may be used more than once or not at all.) a. replication b. tRNA c. conjugation d. ribosome e. transduction f. mRNA g. transcription h. transformation i. translation __________ genetic transfer that occurs after the donor is dead __________ carries the codon __________ a process synonymous with mRNA synthesis __________ bacteriophages participate in this transfer __________ duplication of the DNA molecule ___________ process in which transcribed DNA code is deciphered into a polypeptide

1) = h 2) = f 3) = g 4) = e 5) = a 6) = i

This structure is important for adhesion ___________________ The arrangement of structure C is known as ______________________ Treatment with penicillin will affect which structure? _____________

1) A 2) Lophotrichous 3) B

Match the stages of diseases with what is happening during that stage A) Incubation period B) Prodomal period C) Invasive phase D) Period of decline E) Period of convalescence 1) Major symptoms are evident ____________ 2) Time before first signs or symptoms ____________

1) C 2) A

Indicate whether each of the following conditions is typical of: a) Acute b) Latent c) Subacute d) Chronic The patient experiences cough and breathing problems for months ______ The patient has no apparent symptoms and is a known carrier. ______

1) D 2) B

Determine if the follwoing statements are True or False 1) Viruses do not reproduce 2) Function of the capsid is to protect nucleic acid

1) False 2) True

Fill in the blanks: Sigma factor is a component of _____________________ If the codon for aspartate is 5' CUA, the anticodon is ____________ Mutations that arise without exposure to external agents are called ___________________

1) RNA polymerase 2) 3' GAU 3) spontaneous

Fill in the blanks for the following statments 1) Most RNA viruses carry this enzyme _____________________________ 2) An infectious protein is a ____________________

1) RNA-dependent RNA polymerase 2) Prion

Answer the following questions about the figure above: 1) Antibiotics are most effective during this part of the growth cycle. 2) What is happening in phase (D)? 3) The best time to determine the doubling time is in Phase ___________

1) a and b 2) death phase. Cells are dying and no longer dividing 3) B = log phase

Match the following viruses with the statment below Herpesviridiae Hepadnaviridiae Orthomyxoviridiae Rhabdoviridiae 1) Uses reverse transcriptase _____________ 2) Can be a latent virus _____________

1) b 2) a

Match the statements with the appropriate antibiotic Binds to 50S ribosome ____________ Causes tooth discoloration ____________ a. Streptomycin b. Tetracycline c. Penicillin d. chloramphenicol

1) d 2) b

Determine if the following statements are true or false 1) Staphylococcus is well adapted to the skin because it likes low salt conditions 2) Infants should not be fed raw honey

1) false 2) true

Use the figure below to answer the questions 1) You would say the circle with the number 1 represents a _____________. 2) Of the organisms A, B and C, which are most related. ______________

1) node 2) A and B

Which factors should you consider when using chemicals to control microbial growth 1. How many bacteria you have 2. Time of day 3. How the chemical works

1, 3

Exactly 50 bacteria with a generation time of 20 minutes are introduced into fresh sterile broth at 8:00 am. You measure their growth and don't see any increase in absorbance for 3 hours. You continue monitoring growth until 2 pm. How many generation have the bacteria gone through by 2 pm. How many bacteria are present at 2 pm?

1. 9 2. 50 x 2^9, (# of starting cells) (2^number of generations) = 25600

Match the following as pertaining to: a) RNA b) DNA c) both d) neither 1) A molecule that contains guanine 2) A molecule that is lacking a 2'OH 3) A molecule that supplies sulfur to the cell

1. C 2. B 3. D

What is the net gain of ATP from 6 molecules of glucose that has undergone fermentation is ___________

12

You have a small gene that you wish replicated by PCR. You add fluorescently labeled nucleotides to the PCR machine. After 4 replication cycles, how many double-stranded DNA molecules do you have?

16

For each of the following statements, decide if they are true or false. In food preservation, salts and sugars are used because they create a hypertonic environment ___ An obligate halophile can grow at low and high salt ___ A psychrophile at 50°C is probably dead ___ A facultative anaerobe incubated aerobically will not grow __

1= T 2= F 3=T 4 = F

The following steps occur during multiplication of retroviruses. Put them in order (Please use the numbers) 1.Penetration 2.Attachment 3.Synthesis of double-stranded DNA 4.Synthesis of (+) strand RNA 5.Uncoating

2, 1, 5, 3, 4

A sex pilus is essential for 1. DNA transformation 2. Chromosome transfer by conjugation 3. Plasmid transfer by conjugation 4. Generalized transduction 5. Cell movement

2, 3

Which statements are TRUE? 1. Electron carriers are located at ribosomes 2. ATP is a common intermediate between catabolic and anabolic pathways 3. ATP is used for long-term storage of energy and is often found in storage granules 4. Anaerobic organisms are capable of respiration 5. ATP is generated by the flow of protons across the cell membrane

2, 4, 5

Put the steps required for sporulation in the correct order 1. surrounded by plasma membrane 2. Cell wall synthesis 3. Forespore formation 4. DNA replication

4,1,3,2

Exactly 25 bacteria with a generation time of 30 minutes are introduced into fresh sterile broth at 10:00 am. You measure their growth and don't see any increase in absorbance until 11:30. You continue monitoring growth until 3 pm. How many generations Have the bacteria gone through by 3 pm? How many bacteria are present at 3 pm?

7 generations 25 x 2^7 = 3200

Under ideal conditions, the fermentation of 4 glucose molecule by a bacterium allows a net gain of how many ATP

8

Which statement is FALSE about the three domain system a. Archaea are the least evolved b. Archaea and Eukarya have nothing in common c. Bacteria and archaea have 16S rRNA d. Eukarya are the farthest from the root

Archaea and Eukarya have nothing in common

Use the following terms to fill in the blank A. Prokaryote B. Eukaryote C. Both _________ histones _________ binary fission _________ plasma membrane

B,A,C

Under which of the following conditions will lead to maximal transcription of the lac operon? a. Lactose present/glucose present b. Lactose present/glucose absent c. Lactose absent/glucose present d. Lactose absent/ glucose absent e. Both a and b.

C. Lactose absent/glucose present

All the following are produced during the citric acid cycle EXCEPT: a. FADH2 b. ATP c. O2 d. CO2 molecules e. NADH

C. O2

A DNA chip is based on the principle of ________________________

DNA hybridization

A cell can produce many endospores True or False

False

A cell placed in a hypertonic solution will burst True or False

False

Axial Filaments are outside the cell wall True or False

False

Legionnaires' disease is transmissible by human contact. True or False.

False

Mycoplasma has a cell wall. True or False

False

Proteobacteria are mostly chemoautotrophs. True or False

False

The peplomer is found on a naked virus. True or False

False

Viruses are classified based on biochemical tests. False or True.

False

This compound below is a ___________________ and would be found in the cell in ____________________________ . CH3 - CH2 - CH2 - CH2 - CH2 - CH2 - CH2 - CH2 - CH2 - CH2 - CH2 - COOH

Fatty acid, membrane

In facilitated diffusion molecule moves from area of ____________ concentration to area of _________________ concentration

High, Low

Which of the following pairs is mismatched? a. Endoplasmic reticulum ----- internal transport b. Lysosome ------- protein synthesis c. Golgi complex ----- secretion d. Mitochondrion ----- ATP production

Lysosome ------- protein synthesis

In fermentation, the conversion of pyruvate into a final end product is critical for the production of _______________ and ________________

NAD+, lactic acid

In the absence of oxygen the final electron acceptor for anaerobic respiration could be

Nitrate

Why does reducing your intake of sucrose reduce tooth decay? (two reasons)

No glucose to ferment to make acid No glucose for the formation of dextran

A friend has the flu and knows you are taking microbiology. So, he asks you "What antibiotic would be best to fight the flu? What is your answer and why?

None. This is a viral infection and antibiotics are only used against bacteria or other living organism

Agrobacterium causes crown gall on plants. True or False

True

Antibiotic resistance can be carried on a plasmid. True or False

True

Theta replication starts at the origin of replication True or False

True

You have an Hfr strain that is leu- and tetS and an F- strain that is trp- ala- gln- tetR. These mutations have the following phenotypes: ala- cannot synthesize alanine, tetS sensitive to tetracycline, leu- cannot synthesize leucine, trp- cannot synthesize tryptophan, gln- cannot synthesize glutamine, tetR resistant to tetracycline. You do a conjugation with these cells and select for the transconjugants on the following medium: minimal medium containing tryptophan and tetracycline. What is the likely genotype for the transconjugant? What gene(s) transferred from the Hfr?

a) Leu+ gln+ ala+ tet resistant b) Gln and ala gene transferred

You have an Hfr strain that is TetS and an F- strain that is thr- ala- gly- , TetR. • These mutations have the following phenotypes: TetS sensitive to tetracycline, thrr- cannot synthesize threonine, ala- cannot synthesize alanine, gly- cannot synthesize glycine, TetR resistant to tetracycline. • You do a conjugation with these cells and select for the recombinants on the following medium: minimal medium containing alanine and Tetracycline. a) What is the likely genotype for the recombinants? b) What gene(s) were from the Hfr?

a) ala+/- thr+, gly+ tetR b)thr and gly

Bordetella pertussis a) Is the causative agent of what disease? b) It causes the disease by what mechanism?

a) whopping cough b) Produces a capsule -Allows attachment to ciliated cells in the trachea §Destroys ciliated cells and shuts down the ciliary escalator •Tracheal cytotoxin of cell wall damages ciliated cells Pertussis toxin enters the bloodstream

You have spread a bacteria suspension out over the surface of an agar plate and added disks impregnated with chemical agents X, Y, and Z. Following overnight incubation you make the following observations. A large clear zone surrounds agent Z, the bacteria grow right up to the edge of agent X and Y. Which statement is true: a. the bacteria are most susceptible to agent Z b. the clear zone around an agent is all dead cells c. the bacteria are resistant to agent Z d. the bacteria are susceptible to agents x and y

a. the bacteria are most susceptible to agent Z

The phosphorylation of an antibiotic is an example of which mechanism of resistance? a. Antibiotic inactivation b. Target modification c. Reduced permeability d. Altered metabolic pathway

a. Antibiotic inactivation

Which of the following does not belong with the others? a. Escherchia b. Lactobacillus c. Bacillus d. Stapylococcus e. Streptococcus

a. Escherchia

All of the following are modes of action of antiviral drugs EXCEPT: a. Inhibition of protein synthesis at 70S ribosomes b. Inhibition of RNA synthesis c. Inhibition of uncoating d. Inhibition of DNA synthesis

a. Inhibition of protein synthesis at 70S ribosomes

A biochemical molecule that is found in ALL viruses is: a. Protein b. RNA c. Glycoprotein d. Lipid e. DNA

a. Protein

The following portion of a molecule (ACUGAC) represents a a. RNA b. DNA c. protein d. Lipid

a. RNA

Which of the following methods causes destruction of DNA via mutations? a. Radiation b. Osmotic pressure c. Desiccation d. Heat

a. Radiation

In the lab we sterile our glassware using

autoclave

Symptoms of disease differ from signs of disease in that symptoms a. Always occur as part of a syndrome b. Are change felt by the patient c. Are specific for a specific disease d. Are changes observed by the doctor

b. Are change felt by the patient

The life cycle of the following organism involves elementary bodies a. Borrelia burgdorferi b. Chlamydia trachomatis c. Helicobacter pylori d. Clostridium botulinum e. Treponema pallidum

b. Chlamydia trachomatis

All of the following characteristics apply to enzymes EXCEPT: a. Enzymes are biological catalysts b. Enzymes are consumed in the reaction c. Some enzymes are made entirely of protein d. Heat alters the tertiary structure of enzymes e. Enzymes lower the activation energy of the reaction.

b. Enzymes are consumed in the reaction

Common methods of using moist heat to control growth include all but which of the following: a. Pasteurization b. Incineration c. Non-pressurized steam d. Boiling water e. Steam under pressure

b. Incineration

In a standard growth curve, the growth phase is which there is an increase in cell size and intense metabolic activity is called the a. Log phase b. Lag phase c. Death phase. d. Stationary phase

b. Lag Phase

A commensal bacterium a. Does not receive any benefit from its host b. May be an opportunistic pathogen c. Does not infect its host d. Is beneficial to its host

b. May be an opportunistic pathogen

In terms of lac operon regulation, what happens when E. coli is grown in medium containing both glucose and lactose? a. Lac repressor is bound to the DNA but CAP is not. b. Neither CAP nor the lac repressor are bound to the DNA. c. CAP is bound to the DNA but the lac repressor is not d. Both CAP and the lac repressor are bound to DNA

b. Neither CAP nor the lac repressor are bound to the DNA.

A new antibiotic has been discovered that inhibits bacterial growth by inactivating the binding of 30S ribosomes. Based on this information, the new antibiotic inhibits a. Transcription in eukaryotes b. Transcription in prokaryotes c. Translation in eukaryotes d. DNA synthesis e. Translation in prokaryotes

b. Transcription in prokaryotes

What term would you use for the following temperatures action on bacteria: Generally high temperatures are _________________ and low temperatures are _____________________

bacteriocial, bacteriostatic

Non-envelope viruses enter the cell via: 1) Recognition of a specific receptor 2) Endocytosis 3) Fusion with plasma membrane 4) Binding through a peplomer a. 1,2,4 b. 1,3,4 c. 1,2 d. 1, 3 e. 1,2,3,4

c. 1,2

An antibiotic should a. Only work in vitro b. Work on all eukaryotic cell types c. Act at a specific site d. Work at very high concentrations e. Always be bacteriostatic

c. Act at a specific site

When pathogenic bacterial cells lose the ability to adhere to cells, they a. Increase their virulence b. produce exotoxins c. Become avirulent d. produce endotoxins

c. Become avirulent

Of the choices below, which is the LAST to happen during DNA replication? a. DNA helicase unwinds the DNA ahead of the replication fork b. Primase synthesizes primers for each strand c. DNA ligase joins all the new pieces together d. The two template strands of DNA are unwound e. Primers are removed and replaced with DNA

c. DNA ligase joins all the new pieces together

Phosphenolpyruvate + ADP ------------------- pyruvate + ATP is an example of a(n) a. Anaerobic respiration b. Photophosphorylation c. Substrate level phosphorylation d. Oxidative phosphorylation e. Hydrolysis

c. Substrate level phosphorylation

A new antibiotic binds to the sigma factor of gram negative bacteria, thus interfering with: a. Peptide bond formation b. Plasma membrane function c. Transcription d. Cellular respiration e. Translation

c. Transcription

The envelope of an envelope virus consists of a. Cellular protein b. Viral protein c. Viral protein and viral lipid d. Viral protein and cellular lipid e. Cellular protein and viral lipid

c. Viral protein and viral lipid

In cyclic photophosphorylation? a. CO2 reacts with Rubulose 1,5 bisphosphate b. Oxygen gas is released c. Water donates electrons and protons d. ATP is formed e. NADPH is formed

d. ATP is formed

What is the fate of pyruvate in an organism that uses aerobic respiration? a. It is catabolized in glycolysis b. It is reduced in the Krebs cycle c. It is reduced in the electron transport chain d. It is oxidized in the Krebs cycle e. It is reduced to lactic acid

d. It is oxidized in the Krebs cycle

Some microbes are very resistant to antimicrobial chemicals. Which of the following is the most sensitive to chemical biocides? a. Mycobacteria b. Gram-positive bacteria c. Viruses with lipid envelopes d. Protozoa cysts e. Gram-negative bacteria

e. Gram-negative bacteria

Pick the correct word(s) in each parentheses to complete the sentence. Aerobic respiration of glucose begins with the process of (oxidative phosphorylation, glycolysis) and requires (amino acids, energy) to be supplied by (ATP, NADH) molecules.

glycolysis, energy, ATP

_________________ are the group of microorganisms is most likely to spoil fish preserved with salt

halophiles

If an enzyme's active site became deformed, ____________________ inhibition was most likely responsible.

noncompetitve

Why are pH and time an essential principle for an effective disinfectant?

pH can be acidic or alkaline and could destroy the inanimate object you are trying to sanitize If the procedure takes too long it would not make sense to do it.

___________ is an antibiotic that acts as a competitive inhibitor

sulfonamide

The antibiotic tetracycline binds to the 30S subunit of the ribosome and prevents what specific step _________________

tRNA attachment

Which of the following pairs is mismatched? a. Pasteur ------ fermentation b. Lister ------ aseptic surgery c. Hooke ------cell theory d. van Leeuwenhoek ----- germ theory e. Jenner ----- vaccines

van Leeuwenhoek ----- germ theory