bio ch 17
Immunoassays can be used to detect viruses or bacteria. Place the steps in the process in the correct order, starting at the top. In this case, a virus is detected.
1. a solid surface is coated with antibodies against the virus of interest. 2. an unknown sample is added. 3. an antibody that has been linked to a fluorescent molecule is added. 4. fluorescence is detected.
Place the steps in the process of creating transgenic plants in the correct order starting at the top.
1. the Ti plasmid is isolated from A. tumefaciens. 2. the genes responsible for gall formation are replaced with a gene of interest. 3. the Ti plasmid is re-introduced into A. tumefaciens. 4. A. tumefaciens is used to infect plant cells. 5. transformed plant cells are induced under the proper nutritional and hormonal conditions to produce a mature plant.
How many times does a restriction enzyme cut a double stranded piece of DNA at a given restriction site?
2
Which of the following sequences is a palindrome?
5'-GAATTC-3' In molecular biology, a palindrome is defined as a DNA sequence that reads the same forward and reverse. The reverse of CCTTCC is GGAAGG; therefore this is not a DNA palindrome.
Choose the two mouse lines that a scientist would need to cross in order to produce knockout mice, in which a gene is inactivated only in a specific tissue.
A line that expresses the Cre enzyme from a promoter that is only active in the tissue of interest A line, in which the gene to be knocked out is "floxed"
Choose all that is needed to use the CRISPR/Cas9 system to replace a mutation with a normal gene sequence.
A linear double-stranded DNA which contains the normal sequence of the gene A guide RNA that is complementary to the mutated sequence of the gene
Bacillus thuringiensis is unique in that one of its gene products can act as which of the following?
An insecticide
How is methane produced in a sludge digester?
Archaea metabolize acetate, H2 and CO2 into methane
Which organism produces toxins that kill certain caterpillars and beetles?
Bacillus thuringiensis
A restriction enzyme that cuts both DNA strands in the same position leads to which of the following?
Blunt ends
Which of the following is a stem cell therapy that has been used since 1960 to treat certain cancers?
Bone marrow transplant
How was golden rice created?
By adding genes from daffodils and bacteria to the rice genome
How do restriction enzymes work?
By binding to a specific base sequence and then cleaving the DNA backbone in two locations - one on each strand
How can a TALE protein be engineered to recognize a specific sequence of DNA?
By combining several TALE repeat domains
In the CRISPR/Cas9 system, how is the guide RNA made?
By transcribing viral DNA that has been incorporated into a bacteria's genome
What are the roles of CRISPR and Cas9 in the CRISPR/Cas9 system?
CRISPR binds a guide RNA; Cas9 acts as a nuclease
In a DNA library, DNA fragments are spliced together with a specialized DNA molecule that allows the storage and propagation of the library. What are those specialized DNA molecules called?
Cloning vectors
Which technology can be used to improve stem cell therapy by replacing defective genes in stem cells?
Genome editing
What herbicide kills actively growing plants by inhibiting the enzyme EPSP which is required to produce aromatic amino acids?
Glyphosate
Identify two benefits of glyphosate resistant plants.
Glyphosate breaks down readily in the environment. No weeding is necessary.
What is the term(s) used for a probe attached to a complementary piece of DNA?
Hybridization
Choose all applications of environmental biotechnology.
Increase the sustainability of resources Repair environmental damage Reduce human impact on the environment
What is the expected result of a FISH analysis of HER2 positive cancer cells when observing their hybridized DNA?
Multiple, large dots of fluorescence
The part of a gel where samples are loaded is often called the "top" of the gel; the opposite end of the gel is then referred to as the "bottom" of the gel. After electrophoresis is complete, where will the smallest DNA fragments be found?
Near the bottom of the gel
The second step of a PCR cycle involves which of the following?
Primer annealing
Reverse transcriptase catalyzes which of the following reactions?
RNA to DNA
Which of the following is a method that is used to produce a DNA copy of only the exons of a gene?
RT-PCR
The development of which technology led to the entire field of biotechnology?
Recombinant DNA
Which of the following approaches allows scientists to determine the function of a gene?
Replace a wild-type gene with a mutant copy
Choose the different types of sequences that are typically spotted on a gene chip?
Short DNA probes Short DNA sequences produced by PCR or RT-PCR
Photosynthesis produces reduced carbon that can be metabolically converted to acetyl-coA, which is the building block of fatty acids.
Species A, because it contains more lipids
The third step of a PCR cycle where Taq polymerase uses dNTPs to synthesize complementary DNA strands is referred to as which of the following?
Synthesis
There are two main ways to edit genes in vivo: the TALE (transcription activator-like effector) proteins and the CRISPR (clustered regularly interspaced short palindromic repeats)/Cas9 system.
TALE proteins were identified due to their ability to bind DNA and their role in disease caused by the plant pathogen, Xanthomonas.
What two modifications must be made to the Cas9 protein in order to use the CRISPR/Cas9 system to modulate gene expression?
The Cas9 is made nuclease deficient. The Cas9 is fused to a transcriptional activator or repressor.
How can a TALEN be used to edit the genome of a cell?
The TALE domains recognize a particular DNA sequence and the nuclease cuts it. When the cell repairs the cut, a mutation can be introduced.
A scientist performs FISH on breast cancer cells in order to determine if the cancer is HER2 positive. She observes multiple large dots of fluorescence in the cells. What can be concluded from that test?
The cancer is HER2 positive.
A scientist wants to use the Cre-Lox system can be used to produce knockout mice, in which a gene is knocked out only in the kidney. How can the scientist do that?
The scientist needs to create a mouse line, in which the Cre gene is under the control of a promoter that is only active in kidney cells.
What part of algal cells is used for the production of biodiesel?
Their lipids
How is the DNA in gel electrophoresis typically visualized?
Using a fluorescent dye that binds to DNA
Golden rice is genetically modified to produce β-carotene which alleviates which deficiency?
Vitamin A
Which of the following is a use of bacteria in the advanced treatment stage of wastewater?
Wastewater is treated with bacteria capable of accumulating dissolved phosphorus from the wastewater into cytoplasmic granules
A TALEN is
a TALE protein fused to an nuclease.
In RNA interference,
a gene is silenced by using a small double stranded RNA, which allows scientists to determine the gene's function.
An organism that carries a gene (or genes) from a different species that was introduced via genetic engineering, is called
a transgenic organism
In immunoassays, a molecule is detected by using a specific _____ against it.
antibody
During _____, microorganisms are used to degrade hydrocarbon pollutants in the environment.
bioremediation
The use of microorganisms to degrade or metabolize (incorporate into microbial biomass) hydrocarbon pollutants is called ________.
bioremediation
The polymerase _____ _____ is used to quickly produce millions of copies of a particular DNA sequence.
chain reaction (PCR)
Gene _____, also known as DNA ______ consist of a solid surface, which has been spotted with hundreds to thousands of different DNA sequences.
chips; microarrays
The process of producing a recombinant DNA molecule is often called molecular
cloning
Which best describes the purpose of gene therapy?
defective genes are restored or replaced.
From the list below, identify the general approaches used to introducing foreign DNA into plant cells.
electroporation, physical bombardment, chemical treatment, and bacterial transfer.
The use of biological process to protect and repair the environment from negative human impacts is part of a growing area of biological applications called
environmental biotechnology
DNA _____ is a technology that can identify and distinguish among individuals based on variations in the number of short tandem repeats in their DNA.
fingerprinting
During aerobic secondary treatment of wastewater, bacteria and other organisms form aggregates called _______, where degradation of organic compounds occurs.
floc
Several techniques can be used to insert foreign DNA into plant cells. Whatever technique is used, it is particularly difficult to construct knockout plants because
foreign genes generally insert in a random part of the genome
Scientists introduce mutations in genes in order to understand their
function
The Ti plasmid of A tumefaciens can be used to transform plant cells and create transgenic plants by replacing the genes responsible for _____ formation and replacing them with a gene of interest.
gall or tumor
The branch of medicine, which attempts to treat conditions by restoring or replacing defective genes is called
gene therapy
Because the _____ _____ is nearly universal, a gene from one organism can be placed into a completely different organism and direct the production of the same protein.
genetic code
Scientists can use _____ _____ to restore defective genes in pluripotent stem cells. The modified stem cells can then be infused into a patient to treat certain conditions. This technology has been used with some success to treat patients infected with HIV.
genome editing
The TALE proteins and the CRISPR/Cas9 system are examples of molecular techniques used to perform
in vivo DNA editing
ype I diabetes cannot be cured, but can be managed with daily _____ injections.
insulin
During RNA interference genes are usually
knocked down.
A mouse, which has had one of its genes inactivated, is called a _____ mouse.
knockout
A collection of many different recombinant molecules that can be maintained and replicated (when needed) is called a DNA
library
A cDNA library is produced when ______ is the starting material, complementary DNA is synthesized from it, and the cDNA is inserted into recombinant vectors.
mRNA
Most current therapies involving stem cells use _____ stem cells, which can be used to treat damage to connective tissues such as bone and cartilage.
mesenchymal
Genes from genetically modified corn frequently move to non-genetically modified corn plants because of outcrossing. This is a major concern to
organic farmers, whose fields are close to transgenic corn, because transgenic crops cannot be certified as organic.
The sequences recognized by restriction enzymes are often _____, meaning that the sequence is identical when read in the opposite direction on the complementary strand.
palindromes
DNA libraries containing small pieces of DNA are usually propagated using bacterial _____. When libraries contain large fragments of DNA, they are usually propagated using bacterial or yeast _____ chromosomes.
plasmids; artificial
Molecular cloning is a term often used to refer to the process of
producing recombinant DNA
A single DNA molecule made from two different sources is called _____ DNA.
recombinant
TALE proteins contain several sets of a repeating 34 amino acid sequence known as the TALE
repeat domain
The enzyme reverse transcriptase was isolated from what type of organism?
retroviruses
A scientist constructs two genomic libraries from the same animal, one from kidney cells, and another one from brain cells. These two libraries will have
similar sequences
_____ digesters are sealed reactors used to perform _____ digestion of wastewater.
sludge; anaerobic
_____DNA fragments move faster through a gel polymer than _____ fragments and will be located closer to the bottom of the gel (the part of the gel where DNA fragments are loaded is the "top" of the gel).
smaller; larger
A restriction enzyme that makes single stranded ends that will hydrogen bond to other DNA fragments cut with the same restriction enzyme produces _____ ends.
sticky
In a TALE protein, each TALE repeat can bind a specific nucleotide in DNA. This specificity is determined by the two amino acids present at
the middle two positions of the repeat.
In type I diabetes
the pancreas cannot produce insulin, which results in a rise in blood sugar
During qPCR, fluorescent probes cab be used to detect the synthesis of new DNA in real time because
the polymerase degrades probes that have been annealed to the template releasing the fluorescent tag into solution.
Scientists can use hybridization to detect a specific sequence using a fluorescently or radioactively labeled probe. In the case of FISH
the probe is fluorescently labeled and the target is DNA in cells with intact chromosomes.
A human gene can be placed into the genome of a bacterium, such as E. coli, and the bacterium will make the encoded protein. How is that possible?
this is possible because of the universal genetic code.
The purpose of PCR is
to produce millions of copies of a particular DNA sequence.
True or false: Several new techniques allow scientists to directly edit the genome of living cells.
true
Current next-generation sequencing technologies use
variations of PCR to obtain DNA that will be sequenced.
