Which of the following did Watson and Crick already know when they were trying to determine the structure of DNA? The number of ________.
A) purines is always larger than the number of pyrimidines
B) pyrimidines is always larger than purines
C) cytosines is always the same as adenines
D) guanines is always the same as thymines
E) purines is always the same as pyrimidines

Question

Quizplus · Accepted Answer

Watson and Crick already knew that the number of purines (adenine and guanine) was equal to the number of pyrimidines (cytosine and thymine) in DNA. This knowledge was crucial in determining the structure of DNA, as it allowed them to deduce that the nitrogenous bases must pair up in a complementary fashion (adenine with thymine and cytosine with guanine).

Which of the Following Did Watson and Crick Already Know