Lab Techniques - GRE
Card 0 of 272
The process by which anatomical specimens are separated and analyzed in a detailed manner is termed .
The process by which anatomical specimens are separated and analyzed in a detailed manner is termed .
Dissection is a surgical procedure in which instruments are used to cut and separate tissues for study.
Eviseration is the removal of the organs or the contents of a cavity. Exsanguination describes massive bleeding. Dissociation is the separation of a complex compound into simpler molecules. Dissemination involves spreading something over a considerable area.
Dissection is a surgical procedure in which instruments are used to cut and separate tissues for study.
Eviseration is the removal of the organs or the contents of a cavity. Exsanguination describes massive bleeding. Dissociation is the separation of a complex compound into simpler molecules. Dissemination involves spreading something over a considerable area.
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Bacterial transformations are a useful tool for biologists to replicate valuable plasmid DNA so that it can be used for a myriad of experiments. A student researcher has designed an experiment to determine the effects of pre-incubation duration, heat shock duration, and heat shock temperature on transformation efficiency. The student transformed 1μg of a β**-**lactamase encoding plasmid and recovered the bacteria for 1 hour at 37°C (shaking at 225rpm) for all conditions in Table 1. He then plated the transformed bacteria on ampicillin agar places and observed growth 24 hours later. Table 1 outlines the variables in the experiment.
Of the conditions tested, which condition is optimal to generate a high transformation yield?
Bacterial transformations are a useful tool for biologists to replicate valuable plasmid DNA so that it can be used for a myriad of experiments. A student researcher has designed an experiment to determine the effects of pre-incubation duration, heat shock duration, and heat shock temperature on transformation efficiency. The student transformed 1μg of a β**-**lactamase encoding plasmid and recovered the bacteria for 1 hour at 37°C (shaking at 225rpm) for all conditions in Table 1. He then plated the transformed bacteria on ampicillin agar places and observed growth 24 hours later. Table 1 outlines the variables in the experiment.
Of the conditions tested, which condition is optimal to generate a high transformation yield?
High transformation yield corresponds with the highest transformation efficiency. The condition that had a pre-incubation of 60 minutes, a heat shock duration of 60 seconds, and a heat shock temperature of 42°C had the highest transformation efficiency of 5.5 x 107 cfu/μg.
High transformation yield corresponds with the highest transformation efficiency. The condition that had a pre-incubation of 60 minutes, a heat shock duration of 60 seconds, and a heat shock temperature of 42°C had the highest transformation efficiency of 5.5 x 107 cfu/μg.
Compare your answer with the correct one above
Bacterial transformations are a useful tool for biologists to replicate valuable plasmid DNA so that it can be used for a myriad of experiments. A student researcher has designed an experiment to determine the effects of pre-incubation duration, heat shock duration, and heat shock temperature on transformation efficiency. The student transformed 1μg of a β**-**lactamase encoding plasmid and recovered the bacteria for 1 hour at 37°C (shaking at 225rpm) for all conditions in Table 1. He then plated the transformed bacteria on ampicillin agar places and observed growth 24 hours later. Table 1 outlines the variables in the experiment.
Which variable had the greatest effect on a high transformation yield?
Bacterial transformations are a useful tool for biologists to replicate valuable plasmid DNA so that it can be used for a myriad of experiments. A student researcher has designed an experiment to determine the effects of pre-incubation duration, heat shock duration, and heat shock temperature on transformation efficiency. The student transformed 1μg of a β**-**lactamase encoding plasmid and recovered the bacteria for 1 hour at 37°C (shaking at 225rpm) for all conditions in Table 1. He then plated the transformed bacteria on ampicillin agar places and observed growth 24 hours later. Table 1 outlines the variables in the experiment.
Which variable had the greatest effect on a high transformation yield?
Differences in pre-incubation duration and heat shock duration do not have a large effect on transformation efficiency. However, at a heat shock temperature of 42°C degrees, regardless of the pre-incubation and heat shock durations, the transformation efficiency is at least 105 fold bigger. Thus, heat shock temperature is the most potent variable tested.
Differences in pre-incubation duration and heat shock duration do not have a large effect on transformation efficiency. However, at a heat shock temperature of 42°C degrees, regardless of the pre-incubation and heat shock durations, the transformation efficiency is at least 105 fold bigger. Thus, heat shock temperature is the most potent variable tested.
Compare your answer with the correct one above
Bacterial transformations are a useful tool for biologists to replicate valuable plasmid DNA so that it can be used for a myriad of experiments. A student researcher has designed an experiment to determine the effects of pre-incubation duration, heat shock duration, and heat shock temperature on transformation efficiency. The student transformed 1μg of a β**-**lactamase encoding plasmid and recovered the bacteria for 1 hour at 37°C (shaking at 225rpm) for all conditions in Table 1. He then plated the transformed bacteria on ampicillin agar places and observed growth 24 hours later. Table 1 outlines the variables in the experiment.
If the student researcher had also done trials with a heat shock temperature of 36°C, the resulting transformation yield would most likely be .
Bacterial transformations are a useful tool for biologists to replicate valuable plasmid DNA so that it can be used for a myriad of experiments. A student researcher has designed an experiment to determine the effects of pre-incubation duration, heat shock duration, and heat shock temperature on transformation efficiency. The student transformed 1μg of a β**-**lactamase encoding plasmid and recovered the bacteria for 1 hour at 37°C (shaking at 225rpm) for all conditions in Table 1. He then plated the transformed bacteria on ampicillin agar places and observed growth 24 hours later. Table 1 outlines the variables in the experiment.
If the student researcher had also done trials with a heat shock temperature of 36°C, the resulting transformation yield would most likely be .
For a successful transformation, the heat shock temperature must be higher than the temperature at which the bacteria grows (37°C). This is also the temperature at which the bacteria recover. The heat shock creates pores in the plasma membrane of the cell, allowing the plasmid DNA to enter. If the temperature is not high enough, pores will not form in the membrane and the bacteria will not be transformed; therefore, the transformation efficiency will be zero.
For a successful transformation, the heat shock temperature must be higher than the temperature at which the bacteria grows (37°C). This is also the temperature at which the bacteria recover. The heat shock creates pores in the plasma membrane of the cell, allowing the plasmid DNA to enter. If the temperature is not high enough, pores will not form in the membrane and the bacteria will not be transformed; therefore, the transformation efficiency will be zero.
Compare your answer with the correct one above
Bacterial transformations are a useful tool for biologists to replicate valuable plasmid DNA so that it can be used for a myriad of experiments. A student researcher has designed an experiment to determine the effects of pre-incubation duration, heat shock duration, and heat shock temperature on transformation efficiency. The student transformed 1μg of a β**-**lactamase encoding plasmid and recovered the bacteria for 1 hour at 37°C (shaking at 225rpm) for all conditions in Table 1. He then plated the transformed bacteria on ampicillin agar places and observed growth 24 hours later. Table 1 outlines the variables in the experiment.
If the student realizes that a fraction of the ampicillin agar plates he used to select for transformed bacteria had expired, which conditions would most likely have been grown on expired ampicillin?
Bacterial transformations are a useful tool for biologists to replicate valuable plasmid DNA so that it can be used for a myriad of experiments. A student researcher has designed an experiment to determine the effects of pre-incubation duration, heat shock duration, and heat shock temperature on transformation efficiency. The student transformed 1μg of a β**-**lactamase encoding plasmid and recovered the bacteria for 1 hour at 37°C (shaking at 225rpm) for all conditions in Table 1. He then plated the transformed bacteria on ampicillin agar places and observed growth 24 hours later. Table 1 outlines the variables in the experiment.
If the student realizes that a fraction of the ampicillin agar plates he used to select for transformed bacteria had expired, which conditions would most likely have been grown on expired ampicillin?
If the ampicillin expired, there is no selection for only transformed bacteria to grow. As a result, both transformed and non-transformed bacteria would grow. If the ampicillin were indeed expired, we would expect many more colonies to grow. Conditions 4, 5, and 6 have the highest transformation efficiency (most colonies) and would have most likely been the conditions plated on expired ampicillin.
If the ampicillin expired, there is no selection for only transformed bacteria to grow. As a result, both transformed and non-transformed bacteria would grow. If the ampicillin were indeed expired, we would expect many more colonies to grow. Conditions 4, 5, and 6 have the highest transformation efficiency (most colonies) and would have most likely been the conditions plated on expired ampicillin.
Compare your answer with the correct one above
Bacterial transformations are a useful tool for biologists to replicate valuable plasmid DNA so that it can be used for a myriad of experiments. A student researcher has designed an experiment to determine the effects of pre-incubation duration, heat shock duration, and heat shock temperature on transformation efficiency. The student transformed 1μg of a β**-**lactamase encoding plasmid and recovered the bacteria for 1 hour at 37°C (shaking at 225rpm) for all conditions in Table 1. He then plated the transformed bacteria on ampicillin agar places and observed growth 24 hours later. Table 1 outlines the variables in the experiment.
Besides the indicated variables in table 1, what is most likely the next variable the student would introduce in this experiment to optimize transformation efficiency?
Bacterial transformations are a useful tool for biologists to replicate valuable plasmid DNA so that it can be used for a myriad of experiments. A student researcher has designed an experiment to determine the effects of pre-incubation duration, heat shock duration, and heat shock temperature on transformation efficiency. The student transformed 1μg of a β**-**lactamase encoding plasmid and recovered the bacteria for 1 hour at 37°C (shaking at 225rpm) for all conditions in Table 1. He then plated the transformed bacteria on ampicillin agar places and observed growth 24 hours later. Table 1 outlines the variables in the experiment.
Besides the indicated variables in table 1, what is most likely the next variable the student would introduce in this experiment to optimize transformation efficiency?
The correct answer is varying amounts of DNA. Increasing the amount of plasmid DNA can increase transformation efficiency; however, if too much plasmid DNA is introduced into the transformation, a lawn of bacteria will result.
Electro-competent bacteria are transformed by an entirely different mechanism than described here. The type of incubator used for the heat shock will most likely not produce a noticeable difference. When troubleshooting a transformation, the amount of ampicillin is rarely considered; the amount of ampicillin used to select for transformed bacteria is generally always the same.
The correct answer is varying amounts of DNA. Increasing the amount of plasmid DNA can increase transformation efficiency; however, if too much plasmid DNA is introduced into the transformation, a lawn of bacteria will result.
Electro-competent bacteria are transformed by an entirely different mechanism than described here. The type of incubator used for the heat shock will most likely not produce a noticeable difference. When troubleshooting a transformation, the amount of ampicillin is rarely considered; the amount of ampicillin used to select for transformed bacteria is generally always the same.
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Which of the following techniques would be most useful to study gene expression?
Which of the following techniques would be most useful to study gene expression?
In order to study gene expression it would be useful to quantify the expression of a specific RNA transcript. All of the blotting techniques follow similar procedures, but differ in the macromolecule they separate or the information they obtain. Southern blotting is used for DNA fragments, western blotting is used for proteins, and eastern blotting is used to look at post-translational modifications. Northern blotting would be the most useful in this question, as it is used to look at RNA fragments.
In order to study gene expression it would be useful to quantify the expression of a specific RNA transcript. All of the blotting techniques follow similar procedures, but differ in the macromolecule they separate or the information they obtain. Southern blotting is used for DNA fragments, western blotting is used for proteins, and eastern blotting is used to look at post-translational modifications. Northern blotting would be the most useful in this question, as it is used to look at RNA fragments.
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Which of the following probes are most commonly used in southern blotting?
Which of the following probes are most commonly used in southern blotting?
Southern blotting is a technique used to detect a specific DNA sequence in a sample. The sample is run on an agarose gel and transferred to a membrane. A labeled nucleic acid probe is then incubated with the membrane. The probe carries a tag for identification and will only bind to the target region of DNA. If the tag is identified, then the researcher can conclude that the target gene is present in the sample.
Antibodies are most commonly used to detect specific proteins in western blotting. Biotin-binding proteins have wide uses in both detection and purification procedures. Phosphorous-32 is commonly used to label nucleotides (such as GTP) to perform enzymatic assays.
Southern blotting is a technique used to detect a specific DNA sequence in a sample. The sample is run on an agarose gel and transferred to a membrane. A labeled nucleic acid probe is then incubated with the membrane. The probe carries a tag for identification and will only bind to the target region of DNA. If the tag is identified, then the researcher can conclude that the target gene is present in the sample.
Antibodies are most commonly used to detect specific proteins in western blotting. Biotin-binding proteins have wide uses in both detection and purification procedures. Phosphorous-32 is commonly used to label nucleotides (such as GTP) to perform enzymatic assays.
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Which of the following blots is used to identify known RNA fragments?
Which of the following blots is used to identify known RNA fragments?
A Northern blot is very similar to a Southern blot, except it is used to identify RNA fragments rather than DNA fragments. A gel is used to separate the RNA fragments based on size. A radioactive probe can then be used to identify which known RNA sequences have been combined with an RNA fragment.
A Western blot is used to identify protein subunits and fragments. Eastern blots are used to identify protein modifications, such as glycosylation.
A Northern blot is very similar to a Southern blot, except it is used to identify RNA fragments rather than DNA fragments. A gel is used to separate the RNA fragments based on size. A radioactive probe can then be used to identify which known RNA sequences have been combined with an RNA fragment.
A Western blot is used to identify protein subunits and fragments. Eastern blots are used to identify protein modifications, such as glycosylation.
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A cell line was engineered to contain and express a DNA sequence frequently associated with pancreatic cancer, with the hope that the cell line will undergo rapid cell division much like the cancerous cells. You want to test whether or not the cell line is efficiently transcribing this DNA by measuring the quantity of mRNA produced. Which of the following methods would be best suited for testing this?
A cell line was engineered to contain and express a DNA sequence frequently associated with pancreatic cancer, with the hope that the cell line will undergo rapid cell division much like the cancerous cells. You want to test whether or not the cell line is efficiently transcribing this DNA by measuring the quantity of mRNA produced. Which of the following methods would be best suited for testing this?
Northern blots are designed to detect the quantity and identity of mRNA transcripts in cells or tissue. Electrophoresis separates RNAs by size, and then hybridization is used to detect the mRNA sequence of interest. Southern blots detect DNA sequences, but give no information about whether they are transcribed or not. Western blots detect proteins, but we are not interested in translation. Neither thin-layer chromatography nor two-photon microscopy would tell us anything about the genetic processes occurring in the cell line.
Northern blots are designed to detect the quantity and identity of mRNA transcripts in cells or tissue. Electrophoresis separates RNAs by size, and then hybridization is used to detect the mRNA sequence of interest. Southern blots detect DNA sequences, but give no information about whether they are transcribed or not. Western blots detect proteins, but we are not interested in translation. Neither thin-layer chromatography nor two-photon microscopy would tell us anything about the genetic processes occurring in the cell line.
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Which of the following techniques could help improve the purity of a protein sample while maintaining the protein's native state?
Which of the following techniques could help improve the purity of a protein sample while maintaining the protein's native state?
The only choice that would actually be useful in improving the purity of a protein sample would be column chromatography. It is possible to attach a specific ligand to your protein of interest to help separate it from a mixture via this method.
SDS-PAGE results in a separated, but denatured, protein sample. Detergents used in this process damage the protein structure, making it impossible to retain the native state. Southern blotting is a technique used to identify specific sequences of DNA in a sample and has nothing to do with increasing the purity of a protein sample.
The only choice that would actually be useful in improving the purity of a protein sample would be column chromatography. It is possible to attach a specific ligand to your protein of interest to help separate it from a mixture via this method.
SDS-PAGE results in a separated, but denatured, protein sample. Detergents used in this process damage the protein structure, making it impossible to retain the native state. Southern blotting is a technique used to identify specific sequences of DNA in a sample and has nothing to do with increasing the purity of a protein sample.
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The process by which anatomical specimens are separated and analyzed in a detailed manner is termed .
The process by which anatomical specimens are separated and analyzed in a detailed manner is termed .
Dissection is a surgical procedure in which instruments are used to cut and separate tissues for study.
Eviseration is the removal of the organs or the contents of a cavity. Exsanguination describes massive bleeding. Dissociation is the separation of a complex compound into simpler molecules. Dissemination involves spreading something over a considerable area.
Dissection is a surgical procedure in which instruments are used to cut and separate tissues for study.
Eviseration is the removal of the organs or the contents of a cavity. Exsanguination describes massive bleeding. Dissociation is the separation of a complex compound into simpler molecules. Dissemination involves spreading something over a considerable area.
Compare your answer with the correct one above
Bacterial transformations are a useful tool for biologists to replicate valuable plasmid DNA so that it can be used for a myriad of experiments. A student researcher has designed an experiment to determine the effects of pre-incubation duration, heat shock duration, and heat shock temperature on transformation efficiency. The student transformed 1μg of a β**-**lactamase encoding plasmid and recovered the bacteria for 1 hour at 37°C (shaking at 225rpm) for all conditions in Table 1. He then plated the transformed bacteria on ampicillin agar places and observed growth 24 hours later. Table 1 outlines the variables in the experiment.
Of the conditions tested, which condition is optimal to generate a high transformation yield?
Bacterial transformations are a useful tool for biologists to replicate valuable plasmid DNA so that it can be used for a myriad of experiments. A student researcher has designed an experiment to determine the effects of pre-incubation duration, heat shock duration, and heat shock temperature on transformation efficiency. The student transformed 1μg of a β**-**lactamase encoding plasmid and recovered the bacteria for 1 hour at 37°C (shaking at 225rpm) for all conditions in Table 1. He then plated the transformed bacteria on ampicillin agar places and observed growth 24 hours later. Table 1 outlines the variables in the experiment.
Of the conditions tested, which condition is optimal to generate a high transformation yield?
High transformation yield corresponds with the highest transformation efficiency. The condition that had a pre-incubation of 60 minutes, a heat shock duration of 60 seconds, and a heat shock temperature of 42°C had the highest transformation efficiency of 5.5 x 107 cfu/μg.
High transformation yield corresponds with the highest transformation efficiency. The condition that had a pre-incubation of 60 minutes, a heat shock duration of 60 seconds, and a heat shock temperature of 42°C had the highest transformation efficiency of 5.5 x 107 cfu/μg.
Compare your answer with the correct one above
Bacterial transformations are a useful tool for biologists to replicate valuable plasmid DNA so that it can be used for a myriad of experiments. A student researcher has designed an experiment to determine the effects of pre-incubation duration, heat shock duration, and heat shock temperature on transformation efficiency. The student transformed 1μg of a β**-**lactamase encoding plasmid and recovered the bacteria for 1 hour at 37°C (shaking at 225rpm) for all conditions in Table 1. He then plated the transformed bacteria on ampicillin agar places and observed growth 24 hours later. Table 1 outlines the variables in the experiment.
Which variable had the greatest effect on a high transformation yield?
Bacterial transformations are a useful tool for biologists to replicate valuable plasmid DNA so that it can be used for a myriad of experiments. A student researcher has designed an experiment to determine the effects of pre-incubation duration, heat shock duration, and heat shock temperature on transformation efficiency. The student transformed 1μg of a β**-**lactamase encoding plasmid and recovered the bacteria for 1 hour at 37°C (shaking at 225rpm) for all conditions in Table 1. He then plated the transformed bacteria on ampicillin agar places and observed growth 24 hours later. Table 1 outlines the variables in the experiment.
Which variable had the greatest effect on a high transformation yield?
Differences in pre-incubation duration and heat shock duration do not have a large effect on transformation efficiency. However, at a heat shock temperature of 42°C degrees, regardless of the pre-incubation and heat shock durations, the transformation efficiency is at least 105 fold bigger. Thus, heat shock temperature is the most potent variable tested.
Differences in pre-incubation duration and heat shock duration do not have a large effect on transformation efficiency. However, at a heat shock temperature of 42°C degrees, regardless of the pre-incubation and heat shock durations, the transformation efficiency is at least 105 fold bigger. Thus, heat shock temperature is the most potent variable tested.
Compare your answer with the correct one above
Bacterial transformations are a useful tool for biologists to replicate valuable plasmid DNA so that it can be used for a myriad of experiments. A student researcher has designed an experiment to determine the effects of pre-incubation duration, heat shock duration, and heat shock temperature on transformation efficiency. The student transformed 1μg of a β**-**lactamase encoding plasmid and recovered the bacteria for 1 hour at 37°C (shaking at 225rpm) for all conditions in Table 1. He then plated the transformed bacteria on ampicillin agar places and observed growth 24 hours later. Table 1 outlines the variables in the experiment.
If the student researcher had also done trials with a heat shock temperature of 36°C, the resulting transformation yield would most likely be .
Bacterial transformations are a useful tool for biologists to replicate valuable plasmid DNA so that it can be used for a myriad of experiments. A student researcher has designed an experiment to determine the effects of pre-incubation duration, heat shock duration, and heat shock temperature on transformation efficiency. The student transformed 1μg of a β**-**lactamase encoding plasmid and recovered the bacteria for 1 hour at 37°C (shaking at 225rpm) for all conditions in Table 1. He then plated the transformed bacteria on ampicillin agar places and observed growth 24 hours later. Table 1 outlines the variables in the experiment.
If the student researcher had also done trials with a heat shock temperature of 36°C, the resulting transformation yield would most likely be .
For a successful transformation, the heat shock temperature must be higher than the temperature at which the bacteria grows (37°C). This is also the temperature at which the bacteria recover. The heat shock creates pores in the plasma membrane of the cell, allowing the plasmid DNA to enter. If the temperature is not high enough, pores will not form in the membrane and the bacteria will not be transformed; therefore, the transformation efficiency will be zero.
For a successful transformation, the heat shock temperature must be higher than the temperature at which the bacteria grows (37°C). This is also the temperature at which the bacteria recover. The heat shock creates pores in the plasma membrane of the cell, allowing the plasmid DNA to enter. If the temperature is not high enough, pores will not form in the membrane and the bacteria will not be transformed; therefore, the transformation efficiency will be zero.
Compare your answer with the correct one above
Bacterial transformations are a useful tool for biologists to replicate valuable plasmid DNA so that it can be used for a myriad of experiments. A student researcher has designed an experiment to determine the effects of pre-incubation duration, heat shock duration, and heat shock temperature on transformation efficiency. The student transformed 1μg of a β**-**lactamase encoding plasmid and recovered the bacteria for 1 hour at 37°C (shaking at 225rpm) for all conditions in Table 1. He then plated the transformed bacteria on ampicillin agar places and observed growth 24 hours later. Table 1 outlines the variables in the experiment.
If the student realizes that a fraction of the ampicillin agar plates he used to select for transformed bacteria had expired, which conditions would most likely have been grown on expired ampicillin?
Bacterial transformations are a useful tool for biologists to replicate valuable plasmid DNA so that it can be used for a myriad of experiments. A student researcher has designed an experiment to determine the effects of pre-incubation duration, heat shock duration, and heat shock temperature on transformation efficiency. The student transformed 1μg of a β**-**lactamase encoding plasmid and recovered the bacteria for 1 hour at 37°C (shaking at 225rpm) for all conditions in Table 1. He then plated the transformed bacteria on ampicillin agar places and observed growth 24 hours later. Table 1 outlines the variables in the experiment.
If the student realizes that a fraction of the ampicillin agar plates he used to select for transformed bacteria had expired, which conditions would most likely have been grown on expired ampicillin?
If the ampicillin expired, there is no selection for only transformed bacteria to grow. As a result, both transformed and non-transformed bacteria would grow. If the ampicillin were indeed expired, we would expect many more colonies to grow. Conditions 4, 5, and 6 have the highest transformation efficiency (most colonies) and would have most likely been the conditions plated on expired ampicillin.
If the ampicillin expired, there is no selection for only transformed bacteria to grow. As a result, both transformed and non-transformed bacteria would grow. If the ampicillin were indeed expired, we would expect many more colonies to grow. Conditions 4, 5, and 6 have the highest transformation efficiency (most colonies) and would have most likely been the conditions plated on expired ampicillin.
Compare your answer with the correct one above
Bacterial transformations are a useful tool for biologists to replicate valuable plasmid DNA so that it can be used for a myriad of experiments. A student researcher has designed an experiment to determine the effects of pre-incubation duration, heat shock duration, and heat shock temperature on transformation efficiency. The student transformed 1μg of a β**-**lactamase encoding plasmid and recovered the bacteria for 1 hour at 37°C (shaking at 225rpm) for all conditions in Table 1. He then plated the transformed bacteria on ampicillin agar places and observed growth 24 hours later. Table 1 outlines the variables in the experiment.
Besides the indicated variables in table 1, what is most likely the next variable the student would introduce in this experiment to optimize transformation efficiency?
Bacterial transformations are a useful tool for biologists to replicate valuable plasmid DNA so that it can be used for a myriad of experiments. A student researcher has designed an experiment to determine the effects of pre-incubation duration, heat shock duration, and heat shock temperature on transformation efficiency. The student transformed 1μg of a β**-**lactamase encoding plasmid and recovered the bacteria for 1 hour at 37°C (shaking at 225rpm) for all conditions in Table 1. He then plated the transformed bacteria on ampicillin agar places and observed growth 24 hours later. Table 1 outlines the variables in the experiment.
Besides the indicated variables in table 1, what is most likely the next variable the student would introduce in this experiment to optimize transformation efficiency?
The correct answer is varying amounts of DNA. Increasing the amount of plasmid DNA can increase transformation efficiency; however, if too much plasmid DNA is introduced into the transformation, a lawn of bacteria will result.
Electro-competent bacteria are transformed by an entirely different mechanism than described here. The type of incubator used for the heat shock will most likely not produce a noticeable difference. When troubleshooting a transformation, the amount of ampicillin is rarely considered; the amount of ampicillin used to select for transformed bacteria is generally always the same.
The correct answer is varying amounts of DNA. Increasing the amount of plasmid DNA can increase transformation efficiency; however, if too much plasmid DNA is introduced into the transformation, a lawn of bacteria will result.
Electro-competent bacteria are transformed by an entirely different mechanism than described here. The type of incubator used for the heat shock will most likely not produce a noticeable difference. When troubleshooting a transformation, the amount of ampicillin is rarely considered; the amount of ampicillin used to select for transformed bacteria is generally always the same.
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A certain immunostaining technique initially separates antigens to be identified by electrophoresis, then transfers them to a solid membrane. This process was used as the standard for diagnosis of the presence of human immunodeficiency virus. What process is being described?
A certain immunostaining technique initially separates antigens to be identified by electrophoresis, then transfers them to a solid membrane. This process was used as the standard for diagnosis of the presence of human immunodeficiency virus. What process is being described?
The Western blot test identifies antigens by separating them using electrophoresis on a gel, then transferring to a solid membrane by blotting. The process allows clinicians to establish is a specific protein or set of proteins is present in a sample.
Enzyme-linked immunosorbent assay (ELISA) methodology involves identifying the presence of antigens or antibodies in blood by binding them to enzymes that would result in a color change. In flow cytometry, cells are tagged with an antibody carrying a fluorescent label and passed through a detctor. In immuno-electron microscopy, antibodies are labelled with heavy metals and viewed with an electron microscope. Chemiluminescence is the emission of light as the result of a chemical reaction. Luminol is an example of chemiluminescence.
The Western blot test identifies antigens by separating them using electrophoresis on a gel, then transferring to a solid membrane by blotting. The process allows clinicians to establish is a specific protein or set of proteins is present in a sample.
Enzyme-linked immunosorbent assay (ELISA) methodology involves identifying the presence of antigens or antibodies in blood by binding them to enzymes that would result in a color change. In flow cytometry, cells are tagged with an antibody carrying a fluorescent label and passed through a detctor. In immuno-electron microscopy, antibodies are labelled with heavy metals and viewed with an electron microscope. Chemiluminescence is the emission of light as the result of a chemical reaction. Luminol is an example of chemiluminescence.
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4',6-diamidino-2-phenylindole,commonly known as DAPI, stains what part of the cell when performing immunohistochemistry?
4',6-diamidino-2-phenylindole,commonly known as DAPI, stains what part of the cell when performing immunohistochemistry?
The correct answer is A-T rich DNA. DAPI is a common fluorescent dye used in immunohistochemistry to stain DNA to indicate the localization of the nucleus within a cell, relative to other structures and regions. When bound to DNA, it absorbs ultraviolet light (358nm) and emits blue light (461nm).
The correct answer is A-T rich DNA. DAPI is a common fluorescent dye used in immunohistochemistry to stain DNA to indicate the localization of the nucleus within a cell, relative to other structures and regions. When bound to DNA, it absorbs ultraviolet light (358nm) and emits blue light (461nm).
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When performing whole-mount specimen immunohistochemistry of golgi markers, why is it necessary to porate cell membranes?
When performing whole-mount specimen immunohistochemistry of golgi markers, why is it necessary to porate cell membranes?
When performing immunohistochemistry, antibodies are often utilized to detect proteins of interest within the cell. However, in order for antibodies to enter fixed cells, there must be holes (pores) artificially made in the cell membrane.
When performing immunohistochemistry, antibodies are often utilized to detect proteins of interest within the cell. However, in order for antibodies to enter fixed cells, there must be holes (pores) artificially made in the cell membrane.
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