1. Why salt is added during DNA extraction?
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2. Cold water better than warm water for extracting DNA Give reason
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3.
How is the cell wall of plant cells broken down during the process?
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4. What is the reason of clumping of DNA in alcohol/ isopropanol at the end of extraction?
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5. How long this DNA is stored?
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6. Does chromosome number noticeably affect the mass of DNA?
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1. By adding salt, we help neutralize the DNA charge and make the molecule less hydrophilic, meaning it becomes less soluble in water. The salt also helps to remove proteins that are bound to the DNA and to keep the proteins dissolved in the water. ... The dish soap pulls apart the membranes, releasing the DNA.
2. Why is cold water better than warm water for extracting DNA? Cold water helps keep the DNA intact during the extraction process. ... A cell's DNA is usually protected from such enzymes (called DNases) by the nuclear membrane, but adding detergent destroys that membrane.
3. Mechanical Lysis
Mechanical homogenization can be effectively used to break apart plant cell walls to retrieve the proteins and separate out the starches. In both open-blade mills and rotor-stator homogenizers, blades are used to shear the cells apart, disrupting the rigid cell wall and releasing the proteins.
4. When molecules are insoluble (unable to be dissolved), they clump together and become visible. DNA is not soluble in alcohol; therefore, it makes the DNA strands clump together and become visible to the naked eye.
5. DNA samples stored at 4°C and RT showed varying degrees of evaporation but DNA was stable for up to 12 months at 4°C. Samples stored at room temperature totally evaporated by 6 months (Figure 2).
6. Does chromosome number noticeably affect the mass of DNA you'll see? Cells with more chromosomes contain relatively more DNA, but the difference will not likely be noticeable to the eye. The amount of DNA you will see depends more on the ratio of DNA to cell volume.