Question

what was friedrich mieschers 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 dnas structure. he extracted and observed dna from white blood cells.

Explanation:

Friedrich Miescher extracted and observed DNA from white blood cells. Rosalind Franklin created the first photograph of the structure of DNA (Photo 51). Watson and Crick created the first accurate model of DNA's structure. Chargaff discovered how the DNA bases pair together (Chargaff's rules: A - T, G - C).

Answer:

He extracted and observed DNA from white blood cells.