Who provided X-ray diffraction photographs of purified DNA fibers that suggested a helical structure with a consistent diameter of about 2 nm and a complete helical turn every 3.4 nm?

A. Chargaff
B. Watson and Crick
C. Hershey and Chase
D. Franklin


Answer: D

Biology & Microbiology

You might also like to view...

Pollen comes from the 

A. carpel. B. petal. C. stigma. D. anther. E. style.

Biology & Microbiology

Which of the following is NOT necessary for respiration?

A) cytochromes B) flavoproteins C) a source of electrons D) oxygen E) quinones

Biology & Microbiology

Glucose-6-phosphate is trapped within the cell because __________. Fill in the blank(s) with the appropriate word(s)

Biology & Microbiology

The occurrence of an action potential can best be compared to a

a. switch to turn a lamp on and off. b. volume control on a stereo. c. door to a classroom. d. room light dimmer switch. e. gradually inclined ramp.

Biology & Microbiology