Biology 9700 · AS & A Level · Proteins

Proteins — practice question

In DNA, the X base Y pairs with adenine through Z hydrogen bonds. Which row correctly finishes the statement about DNA?

  • AX: purine, Y: thymine, Z: three
  • BX: purine, Y: uracil, Z: three
  • CX: pyrimidine, Y: thymine, Z: two
  • DX: pyrimidine, Y: uracil, Z: two

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