During gel electrophoresis, the DNA sample is mixed with the tracking dye, in order to Choose one answer. Visualize DNA bands at the end All of the above To make the sample loading easy To reduce the carcinogenic nature of the material being used

20. During gel electrophoresis, separated DNA fragments can be seen as bright orange coloured bands when they are0/4a. Stained with ethidium bromide and exposed to IR radiation.b. Stained with methylene blue and exposed to UV radiation.c. Stained with methylene blue and exposed to IR radiation.d. Stained with ethidium bromide and exposed to UV radiation. 21. After gel electrophoresis, DNA bands are cut out from agarose gel. This is called0/4a. Elutionb. Transformation c. Denaturationd. AnnealingCorrect answera. Elution 22. A small piece of DNA molecule that can carry a foreign DNA segment and replicate inside the host cells is known as0/4a. Marker geneb. Primerc. Cloning vectord. Ori 23. Autonomously replicating circular extra-chromosomal DNA of bacteria is called0/4a. Marker geneb. Plasmidsc. Cosmidsd. BAC 24. Which of the following cloning vectors has very high copy numbers of their genome?0/4a. Plasmidsb. YACc. Bacteriophagesd. BAC 25. The function of a selectable marker is0/4a. Eliminating tarnsformants and permitting non-transformantsb. Elimination of non-transformants and permitting transformantsc. Identify ori sited. To destroy recognition sites 26. Select the wrong statement.0/4a. Transformation is a procedure through which a piece of DNA is introduced in a host bacterium.b. Selectable markers of E. coli include the genes encoding resistance to antibiotics like ampicillin, chloramphenicol, tetracycline, etc.c. Normal E. coli cells have resistance against ampicillin, chloramphenicol etc.d. To link the alien DNA, the vector needs a single or very few recognition sites for restriction enzymes.

What is the purpose of using a stain that binds to DNA and fluoresces under UV light? It assists with loading DNA fragments into wells It gives the DNA a negative charge so it will travel through the gel It gives the DNA a positive charge so it will travel through the gel It allows us to visualise where DNA fragments are positioned along the gel

give me a brief introduction on gel electrophoresis

RECAP – DNA standards of known sizes (the “DNA ladder”) were loaded into the first well of the gel.  Samples of the PCR products from the WT and CRISPR-Cas9-treated N. tabacum (A – E) were loaded into the remaining wells.  An electric current was applied to drive the DNA through the gel.  The DNA was stained and the gel was viewed under ultraviolet light and an orange filter.ResultsThe results of the gel run are below. Complete the drag and drop activity so that the results can be analysed.Complete the questions below to analyse the data1. QuestionEnter a numerical value top estimate the sizes (in base pairs, bp) for each of the PCR fragments in the lanes for the N. tabacum samples:WT: bpA: bpB: bpC: bpD: bpE: bp (largest fragement) & bp (smallest fragment)2. QuestionEvaluate the results:The scientists want to conduct tests on plants in which the SSU gene has been disabled by a CRISPR-Cas9 deletion. Based on the data, select the plants (A-E) that you would continue to work with. A B C D E3. QuestionJustify your conclusion:

Gel electrophoresis separates fragments of DNA according to what property? Length in nucleotides Organism they originate from Protein they code for2. QuestionWhat is the overall charge on DNA? Positive charge Negative charge DNA has no charge3. QuestionReferring to the image below, on which side of the gel tank should the positive electrode be placed so that DNA in the well migrates in the direction of the arrow? Left side Right side4. QuestionTwo fragments of DNA are loaded into a well on a gel. One fragment is 50 nucleotides in length, the other fragment is 200 nucleotides in length. A current is applied to the gel for 10 minutes. Which fragment will migrate further through the gel? The fragment that is 50 nucleotides in length The fragment that is 200 nucleotides in length Both fragments will travel the same distance5. QuestionWhat is the purpose of using a stain that binds to DNA and fluoresces under UV light? It assists with loading DNA fragments into wells It gives the DNA a negative charge so it will travel through the gel It gives the DNA a positive charge so it will travel through the gel It allows us to visualise where DNA fragments are positioned along the gel6. QuestionThe image below shows the results of a gel run. Based on these results, which of the following statements is correct? The DNA fragments in band A are shorter than the DNA fragments in band C The DNA fragments in band A are longer than the DNA fragments in band C The DNA fragments in band A are roughly the same length as the DNA fragments in band C7. QuestionBased on the gel results in the previous question, which of the following statements is correct? The DNA fragments in band B are shorter than the DNA fragments in band C The DNA fragments in band B are longer than the DNA fragments in band C The DNA fragments in band B are roughly the same length as the DNA fragments in band C8. QuestionEach person inherits two copies of a certain gene from their biological parents. There are two versions of the gene that can be inherited, version A and version B. Version A is longer than version B.DNA samples are collected from three patients. The gene of interest is copied using PCR and each sample is loaded into wells on a gel. The gel is run and a DNA profile is obtained (as seen in the image below). Which versions of the gene does each patient have? Justify your response.