Question

what was friedrich miescher’s contribution to the discovery of the genetic code?
○ he created the first photograph of the structure of dna.
○ he discovered how the dna bases pair together.
○ he created the first accurate model of dna’s structure.
○ he extracted and observed dna from white blood cells.

Explanation:

Friedrich Miescher's contribution was extracting and observing DNA from white blood cells. The first photograph of DNA's structure was by Rosalind Franklin, base pairing discovery and DNA model creation were by other scientists (like Watson, Crick, and others related to base pairing research). So the correct option is the one about extracting DNA from white blood cells.

Answer:

D. He extracted and observed DNA from white blood cells.