哪些核苷酸碱基存在于RNA中？ A: adenine, guanine, cytosine, thymine B: adenine, guanine, thymine C: adenine, guanine, cytosine, uracil D: sugar, phosphate and base

What is Chargaff’s ratio? () A: In any organisms, amount of Adenine is the same as Thymine, amount of Cytosine is the same as Guanine. B: In any organisms, amount of Adenine is the same as Cytosine, amount of Thymine is the same as Guanine. C: In any organisms, amount of Adenine is the same as Guanine, amount of Thymine is the same as Cytosine.

5-bromouracil is an analog of which base? A: thymine B: uracil C: cytosine D: adenine

In DNA molecule, the adenine content is 15%,so the cytosine content is :() A: 0.15 B: 0.3 C: 0.4 D: 0.35 E: 0.07

下列非糖物质能合成葡萄糖的是（） A: alanine B: glycerol C: lactate D: palmiticacid E: adenine

If the cytosine content of double helical DNA is 40% of the total bases, the adenine content would be: A: 10% B: 60% C: 40% D: 30% E: 20%