Basically, the primary structure of a nucleic acid is: ____
A. the sequence of bases in the polynucleotide chain
B. the way of bases pairing in the polynucleotide chain
C. the ratio of bases in the polynucleotide chain
D. the way of coiling and folding in the polynucleotide chain
E. the linkage between groups in polynucleotide chain
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Which of the following is false about the double helix structure of DNA: ____
A. DNA consist of two anti-parallel strands.
B. Nitrogen bases are strictly paired in double helix.
C. The sugar and phosphate groups face outward of double helix.
D. Base plane is perpendicular to the central axis.
E. DNA is found in the right-handed configuration in all organisms.
Which of the following is false about the content of bases in DNA: ____
A+T=C+G
B. A+G=C+T
C. G=C
D. A=T
E. A/T=G/C
Which of the following is not included in DNA____
A. phosphodiester
B. glycosidic bond
C. hydrogen bond
D. disulfide bond
E. Van der Waals' force
The secondary structure of DNA is: ____
A. α- helix
B. β- sheet
C. β- turn
D. double helix
E. random coli
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