Which of the following statement is NOT true about the virulence transformation experiment of Diplococcus pneumonia carried out by Griffith and Avery:____
A. Only S type of Diplococcus pneumonia has the capsule which is similar to cell wall.
B. In Griffith’s experiment, if S type strain and heat-denatured R type strain was injected into mice, the mice would not die.
C. The virulence transformation of bacterial strain is mainly related to the capsule of the S type strain.
D. The transformation of alive R type strain to S type strain could also happen in the tube besides happening in vivo in the mice.
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When running DNA agarose gel electrophoresis, which of the following is NOT true:____
A. Melted agarose should be cooled for a while before transferred into gel tank
B. Put the sample well on the positive side of the electrophoresis chamber and load the samples
C. After the gel was ready, add electrophoretic buffer and then pull out the comb
D. Mix the sample solution with loading buffer and then load them in the sample well
E. Use ethidium bromide (EB) to stain the gel after running and check the bands under UV light
Which of the following statements about the structure of nucleic acid is NOT true:____
A. There are major and minor grooves on the surface of double helix
B. There is base stacking force between upper and lower layers of bases
C. The double helix structure only exits in DNA molecule
D. The double helix structure also exits in RNA molecule
E. There is complementary base pairing existing in the double helix structure
Below are the two molecules that has been heat-denatured, when temperature of the solution was dropping slowly, which one would be easier to recover:____
A. 5’-ATATCATATGATATGTA-3’
B. 5’-CGGTACTCGTGCAGGT-3’
DNA molecule does not include:____
A. phosphodiester bond
B. glycosidic bond
C. hydrogen bond
D. disulphide bond
E. Van der Waals' force
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