Micro Bio

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A plasmid that can directs its own transfer from donor to recipient cells is called a(n) ___________plasmid

conjugative plasmid

There are two types of transduction: _________________, which transfers any genes of the donor cell, and , ___________________which transfers only a few specific genes.

generalized; specialized

"Jumping genes," or ,___________ can move within a cell without specificity as to where they ultimately insert.

transposons

When integrated F plasmid DNA in an Hfr cell is excised from the chromosome, an excision error can result in the removal of chromosomal DNA along with the F plasmid DNA, creating a plasmid called ______. Multiple choice question. F+ Hfr F- F'

F'

A n incorrect excision (to cut out entirely) of the integrated F plasmid brings along a portion of the chromosome, generating an ________cell

F' or F prime

Chromosomal DNA transfer is less common than plasmid transfer and involves ______________ cells. These are strains in which the F plasmid has integrated into the chromosome by homologous recombination, which happens on rare occasions.

F' or F prime

When an excision errors produces a plasmid containing both chromosomal and F plasmid DNA, the resulting plasmid is called a(n)________________ plasmid.

f'

In the most thoroughly studied example of bacterial conjugation, the term designates ______________ a donor cell with an F plasmid, whereas those cells who lack the F plasmid are termed _______________.

f+ or F plus ; f- of F minus

True or false: In bacterial conjugation, all F+ donor cells are high frequency recombinant (Hfr) cells. True false question.TrueFalse

false

A(n)_______________ is a large segment of a cell's genome that has clearly originated in a different species.

genomic islands

Which of the following are examples of mobile genetic elements? Multiple select question. plasmids genomic islands phage DNA chromosomal DNA transposons

plasmids, transposons, genomic islands, and phage DNA

Protection against the toxic effects of antimicrobial compounds or heavy metals is often encoded on plasmids called _________ plasmids.

R plasmid or resistance

A bacteriophage consists of a genome made up of DNA or ____________, surrounded by a coat made up of ___________.

RNA, protein

What type of nucleic acids is it if there are 20A, 30T, 20G, and 40C in the molecule? a. double stranded DNA b. double stranded RNA c. single stranded DNA d. single stranded RNA

A,T,G and C are DNA sequences therefore it has to be DNA. also it must be double strand because A<T<G<C must have strand connect to it must match. , A bonds to another A, T-T and so on.

Which of the following plasmids encodes all the necessary genetic information for transfer from one bacterial cell to another? Multiple choice question. Both conjugative and mobilizable plasmids Mobilizable plasmids only Conjugative plasmids only

conjugation plasmids only

Conjugation in bacteria requires ______. Multiple choice question. the isolation of chromosome fragments formation of a biofilm matrix contact between donor and recipient cell the presence of bacteriophages

contact between donor and recipient cell

True or false: In bacterial conjugation, all F+ donor cells are high frequency recombinant (Hfr) cells. True false

false ;Although both types of donors have plasmid DNA, only the Hfr cell has the plasmid integrated into the chromosome.

Plasmids are insertion sequences that can lead to changes in genotype within a cell or between cells. true or false

false: Insertion sequences that can lead to changes in genotype within a cell or between cells are called transposase. Plasmids are small circular pieces of DNA.

The structure connecting these two cells is called an F _______and is formed during the mechanism of DNA transfer called ___________ .

pilus; conjugation

________ are circular pieces of bacterial DNA that do not usually encode information essential to the life of a cell.

plasmid

This figure shows a cell with an integrated F plasmid. If this plasmid is incorrectly excised, the result could be an F plasmid that carries along a portion of the bacterial chromosome. Such a cell would then be called a(n) _____________cell.

Hfr (high frequency recombination cells)

An origin of transfer is encoded by _______. Multiple choice question. both conjugative and mobilizable plasmids neither conjugative nor mobilizable plasmids mobilizable plasmids only conjugative plasmids only

both conjugative and mobilizable plasmids

A bacterial cell described as can ____________take up DNA from the surrounding environment.

competent

During ___________ recombination, a segment of DNA inserts into the cell's genome, a process that does not require a similar

non-homologous : a process that not require a similar nucleotide sequence in the region of recombination. transposons inter=grate into their new location through non-homologous recombination.

Donor and recipient bacterial cells are connected by a sex ______ during conjugation. Multiple choice question. pilus membrane fimbria cilium receptor

Pilus

A large segment of a cell's genome that originated in other species is called a(n) ______. Multiple choice question. genomic library virulence factor genomic imprint fertility factor genomic island

genomic island

bacterial transformation

ability of bacteria to alter their genetic makeup by uptaking foreign DNA from another bacterial cell and incorporating it into their own

The genes that are present in all strains of a given species are called the ______. Multiple choice question. plasmid genome pan genome core genome basal genome

core genome

Plasmids with a copy ____________number occur in only one copy per cell, while those with a ___________-copy number are present in many copies per cell. A. high b. low c. reduced. d. decreased

low; high

A(n) _____________is a virus that infects bacteria, and some can transfer bacterial genes from a donor cell to a recipient cell.

phages

am)_______________ is a virus that infects bacteria, and some can transfer bacterial genes from a donor cell to a recipient cell

bacteriophage or phage

Which of the following statements about transformation is correct? Multiple choice question. Transformation is the transfer of DNA from one bacterial cell to another by means of a bacteriophage. Transformation depends on a donor cell containing an F plasmid and a recipient cell that does not. Transformation is the uptake of naked DNA from the environment. Transformation involves the formation of a sex pilus through which plasmid DNA is shared between bacteria.

Transformation is the uptake of naked DNA from the environment.

Because CRISPR systems involve bacteria using retained segments of DNA to identify and destroy future invading phage DNA, these systems are a form of ______. Multiple choice question. predictive modeling adaptive immunity innate immunity

adaptive immunity

Plasmids with a ----------- copy number occur in only one copy per cell, while those with a _____________-copy number are present in many copies per cell.

low; high

______ is the transfer of bacterial DNA from a donor to recipient via a bacteriophage.

Transduction

After new virus particles have assembled in the bacterial host cell, they are usually ______. Multiple choice question. integrated into the structure of the bacterial cell wall stored inside the cell for a later time destroyed by the bacterial immune system released as a result of host cell lysis

released as a result of host cell lysis

"generalized transduction" results from a rare error that sometimes occurs during the construction of ______________. A fragment of bacterial DNA (produced when the phage- encode enzyme cuts the bacterial genome) mistakenly enters the phage protein coat. This error creates what is called _______________.

phage particles; transducing particle

Transduction exists in two kinds. What are they? Multiple select question. specific compartmentalized specialized nonspecific localized generalized

generalized and specialized

___________________transduction results from a packaging error during the virus replication cycle, when a piece of bacterial DNA is included in the new virus particle.

generalized transduction

Which of the following are characteristics of recombinants? Multiple select question. The have properties of both donor and recipient cells. They have multiple chromosomes. They are genetically identical to their parent strain. They result from horizontal gene transfer.

The have properties of both donor and recipient cells. They result from horizontal gene transfer.

When describing conjugation in Gram-negative bacteria, a donor cell with an F ______ is considered F+, while that without this structure are termed F-. Multiple choice question. plasmid cilium flagellum fimbria chromosome

pasmid

A bacterial virus is known as a(n) _______. Multiple choice question. prion phage bacteriovirus elementary body retrovirus

phage

In generalized transduction, donor DNA is mistakenly packaged into a phage coat, forming a ____________ particle

phage

conjugative plasmid a. is a complex process that requires contact between donor and recipient bacterial cells. b. direct their own transfer from donor to recipient cell. d. none

direct their own transfer from donor to recipient cell.

plasmids are commonly found in the microbial world and are found in many bacteria and archaea and some eukarya such as yeast. like chromosomes, most plasmids are circular _________ stranded DNA molecules.

double

after a semi-conservative replication of a dsDNA to two dsDNA molecules?

each daughter dsDNA contains an old strand and a new strand.

Which of the following can be found in a bacteriophage? Multiple select question. hybrid DNA/RNA genome protein genome protein coat lipid membrane nucleus DNA or RNA genome

either DNA or RNA never both surrounded by a protein coat

True or false: When an Hfr cell transfers chromosomal DNA to a recipient cell, it does not need to produce an F pilus. True false question.TrueFalse

false

Plasmids, transposons and phage DNA are all examples of ______. Multiple choice question. mobile genetic elements conserved core genetic sequences

mobile genetics elements.

When two bacterial strains that are His-/Trp- (require his and trp for growth) and Leu-/Thr- (require leu and thr for growth) are mixed together and plated on minimal media, any colonies that form are likely due to one strain acquiring genes from another strain. This is called _____________ gene transfer.

horizontal

The codon 5' UGC 3' on mRNA encodes for cysteine. which sequence represents an anticodon from the 5' to 3' direction? a. UGC b TGC c. ACG d. GCA

D. GCA

what enzyme synthesizes the short segment of RNA required to initiate DNA replication?

DNA polymerase

Conjugation

cell to cell contact

Hfr strains can revert to F+ because the process of F plasmid integration is ______________.

reversible

Although mobilizable plasmids encode an origin of transfer, they lack other genetic information required for transfer. Under what circumstances can a mobilizable plasmid be transferred to another bacterial cell? Multiple choice question. when a conjugative plasmid is present in the same cell when two different mobilizable plasmids work together to transfer when the mobilizable plasmid is present in a Gram-negative cell when the mobilizable plasmid is present in a Gram-positive cell

when a conjugative plasmid is present in the same cell

Although mobilizable plasmids encode an origin of transfer, they lack other genetic information required for transfer. Under what circumstances can a mobilizable plasmid be transferred to another bacterial cell? Multiple choice question. when the mobilizable plasmid is present in a Gram-negative cell when a conjugative plasmid is present in the same cell when the mobilizable plasmid is present in a Gram-positive cell when two different mobilizable plasmids work together to transfer

when a conjugative plasmid is present in the same cell

CRISPR systems were discovered ______. Multiple choice question. in yeast strains that capable of fermenting a wide array of substrates when scientists recognized that certain bacterial genomes include very small pieces of phage DNA during global efforts to develop human vaccines for common viral infections in all three domains of life

when scientists recognized that certain bacterial genomes include very small pieces of phage DNA

Restriction-modification systems were discovered ______. Multiple choice question. in all three domains of life during efforts to develop vaccines for common viral infections while studying why certain bacterial strains are relatively resistant to phage infection in yeast strains that capable of fermenting a wide array of substrates

while studying why certain bacterial strains are relatively resistant to phage infection

When bacteriophages replicate, phage components are synthesized in the host cell and assemble into new viruses ______. Multiple choice question. when the bacterial cell enters a new eukaryote host within that cell before being released after the components are released from the host cell within the nucleus of the host cell before release

within that cell before being released

Is integration of F plasmid reversible?

yes, Hfr cells these are strains in which F plasmid has integrated into chromosome by homologous recombination. Integration of F plasmid is reversible; same process that generates an Hfr cell also allowing the integrated plasmid to excise(to cut out entirely) from the chromosomes.

Chromosomal DNA is transferred with F plasmid DNA in an Hfr cell because ______. Multiple choice question. the chromosomal DNA is homologous with the plasmid DNA the chromosomal DNA is fragmented into segments the plasmid DNA and chromosomal DNA are similar in size the plasmid DNA is integrated into the chromosome in these cells

the plasmid DNA is integrated into the chromosome in these cells

transducing vs transduction

tranduction: there are two types, generalized transduction which transfers any genes of the donor cell. whereas specialized transduction which transfers only s few specific genes. - transducing is a particle, transducing particle which is an error created during generalized transduction by a fragment of bacterial DNA mistakenly enters the phage protein coat.

In generalized transduction, donor DNA is mistakenly packaged into a phage coat, forming a _________ particle.

transducing

In this diagram, step 5 was left out on purpose. You would expect it to show the formation of a _______. Multiple choice question. transformative particle conjugative particle plasmid particle transposable element transducing particle

transducing particle

The mechanism by which bacterial DNA is moved from one bacterium to another by a bacteriophage is called ________.

transduction

How many codons are used to specifically the 20 possible amino acids? a. 30 b. 61 c. 20 d. 3 e. 64

61

When horizontal gene transfer occurs between a donor and recipient cells, the resulting cells are called_________

recombinants

Plasmids that encode resistance to a variety of antimicrobial agents and heavy metals are called Blank______ plasmids or factors. Multiple choice question. F X A Ti R

resistance or R plasmids are particularly important medically because they encode resistance to antimicrobial chemicals including antibiotics. Many of these plasmids are conjugative and also have genes for pilus synthesis and other properties required for conjugation.

Which of the following are systems bacteria can use to protect against invading DNA? Multiple select question. immunoglobulin formation restriction-modification microarrays polymerase chain reaction CRISPR

restriction-modification and CRISPR

CRISPR systems involve ______. Multiple choice question. enzymes that protect bacterial cells from cold temperatures retained segments of phage DNA used by bacteria to recognize and destroy future invading DNA enzymes that recognize and cut at a specific sequence of nucleotides

retained segments of phage DNA used by bacteria to recognize and destroy future invading DNA

Neither strain A (His-/Trp-) nor strain B (Leu-/Thr-) can grow on minimal media on their own because they cannot synthesize the indicated amino acids. If the strains are mixed and then plated onto minimal media, any colonies that form ______. Multiple choice question. do not use any of those amino acids for growth should be a result of horizontal gene transfer are likely to be spontaneous mutants

should be a result of horizontal gene transfer

During conjugation, the F plasmid nucleic acid that transfers is ______. Multiple choice question. double-stranded DNA double-stranded RNA single-stranded DNA single-stranded RNA

single stranded DNA

The process of bacterial _______________involves the uptake of "naked" DNA by competent bacterial recipient cells.

transformation

Which of the following are the three main methods of gene transfer in bacteria? Multiple select question. transformation translocation transduction competition conjugation transposition

transformation, transduction. and conjugation

Which of the following are components of the simplest transposon, an insertion sequence? Multiple select question. transposase gene reverse transcriptase antibiotic resistance gene origin of replication inverted repeats

transposase gene inverted repeats

transposons vs transposase

transposase is the enzyme responsible for transposition; on each side of the gene 5'- 3' sequence inverted repeats - transposons : provide a mechanism for transferring various genes

Place the steps of F plasmid transfer in the correct order. Start with the earliest at the top.

1. F pilus makes contact with recipient cell. 2. One strand of F plasmid is cut in origin of transfer. 3. single strained of F plasmid is transferred to the recipient cell, 4. complement of the transferred strand is synthesized.

In conjugation in E. coli, an Hfr cell refers to ______. Multiple choice question. a cell with an intact F plasmid which is separate from the chromosome a cell that has donated its F plasmid to a recipient cell a cell in which the F plasmid has been integrated into the cell chromosome a cell that has combined with the other cells by sexual reproduction a cell in which the F plasmid has been degraded by DNase

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

which is the shared property of the transcription and RNA processing in the prokaryotes and eukaryotes? a. promoters are required b. introns need to be removed. c. RNA are exported from nucleus d. mRNA are polyadenylated.

a. promoters are required incorrect because- mRNA are polyadenylated (only in eukaryotic cells)

define plasmid

is a genetic structure in a cell that can replicate independently of the chromosomes typically in bacteria and protozoa.

During a viral infection of a bacterial cell, the viral DNA can be integrated into the host chromosome. The DNA is then called a(n)_________--.

prophage prophage: originates from phage DNA , certain types of phages can insert their DNA into the host cell chromosome. when this occurs, the phage DNA becomes part of the host cells genome, which will be replicated and passed on to progeny cells. When inserted into host cells DNA that phage DNA is called a prophage.

In insertion sequences, the _____________ gene (the only gene) is flanked by ___________repeats.

transposase ; inverted

Cells that have the ability to take up DNA from the environment are called ______ cells.

competent

The difference between transfer of F plasmid and Hfr select all that apply a. when an Hfr transfer chromosomal DNA, the process involves the same general steps for transfer of the F plasmid. b. Hfr cells produce an F pilus and the F plasmid DNA directs its transferred, to the recipient cell. c. the F plasmid DNA is integrated into the chromosome, chromosomal DNA is also transferred, beginning with the genes on one side of the origin of transfer.

all are correct

Many bacteria are able to recognize and destroy invading DNA. It is thought this ability evolved ______. Multiple choice question. as a defense against prions as a defense against phages during host-pathogen competition with mammalian hosts from competition among species of bacteria

as a defense against phages

During bacterial conjugation, synthesis of a new strand of F plasmid DNA occurs in ______. Multiple choice question. neither the donor nor the recipient the donor only both the donor and recipient either the donor or the recipient, but not both the recipient only

both the donor and recipient- 'conjugation is cel to cell contact"

Which of the following plasmids are self-transmissible? Multiple choice question. conjugative plasmids only both conjugative and mobilizable plasmids mobilizable plasmids only neither conjugative nor mobilizable plasmids

conjugative plasmids are self transmissible, meaning they carry all of the genetic information needed for transfer, including origin of transfer.

In E. coli, less than 50% of the genes are found in all strains. These conserved genes are called the _______genome.

core

synthesis of lagging DNA strand in correct order: A. DNA synthesis, B.RNA synthesis, C. DNA ligation, D. RNA removal and DNA replacement

B-A-D-C

restriction modification system

Primary defense against phages Involves 2 types of enzymes 1. Restriction enzymes (restriction endonucleases) 2. Modification enzymes

____________________an error which carries no phage DNA and therefore is not phage.

transducing particle

In generalized transduction, donor DNA is mistakenly packaged into a phage coat, forming a _________ particle.

transduction

What is a prophage? Multiple choice question. a mobile genetic element that carries antibiotic-resistance genes another term for a virus that can infect bacteria viral DNA that has been integrated into a bacterial chromosome bacterial virus that contains a plasmid

viral DNA that has been integrated into a bacterial chromosome

which are correct statements? a. a peptide bond is formed between amino acid s carried by adjacent tRNAs. b. Amino acids are joined together by RNA polymerase. c. tRNA carrying amino acids occupy the E-site and P-site of the ribosomes. d. empty tRNA leaves vis the E site.

A and D

phage particle vs transduction particle?

like phage particles, a transducing particle will attach to another bacterial cell and inject the DNA it contains. The bacterial DNA may then integr

The integration of a region of DNA into a segment that does not have extensive similarity in nucleotide sequence is called ______. Multiple choice question. specialized transduction non-homologous recombination homologous recombination generalized transduction horizontal gene transfer

non-homologous recombination

Place the steps of DNA-mediated transformation into the correct order. Start with the earliest at the top. strand replaced by donor DNA is degraded single-stranded DNA integrates into genome after entering the cell. double-stranded DNA molecule binds to surface receptor. nucleases at the cell surface degrade one strand of the DNA; the other strang enters the call.

1.double-stranded DNA molecule binds to surface receptor. 2. nucleases at the cell surface degrade one strand of the DNA; the other strang enters the call. 3. single-stranded DNA integrates into genome after entering the cell. 4. strand replaced by donor DNA is degraded

The CRISPR system has been called the immune system of bacteria. It helps protect bacteria from a repeat infection because bacterial cells ______. Multiple choice question. integrate phage DNA fragments in their own chromosomes and target for destruction any DNA encountered later that contains the same sequences modify the attachment sites for the phages so that new infections cannot take place integrate fragments from the phage RNA in their own chromosomes and target for destruction any RNA that contains the same fragments in the future recognize proteins on the surface of the phage and secrete proteins that block the binding of the phage recognize proteins on the surface of the phage and secrete enzymes that digest the phage

integrate phage DNA fragments in their own chromosomes and target for destruction any DNA encountered later that contains the same sequences

In transformation, only one daughter cell inherits donor DNA. This is because ______. Multiple choice question. the parent cell keeps one strand of donor DNA and donates the other to one daughter cell. only a single strand of donor DNA integrates into the recipient chromosome the other daughter cell rejects the donor DNA strand

only a single strand of donor DNA integrates into the recipient chromosome


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