In 1952, Rosalind Franklin took an X-ray photograph that revealed the structure of DNA. James Watson and Francis Crick followed up on this discovery in 1953. They discovered that the molecule has a specific shape that can best be described as — A. a single strand containing 4 different bases that vary depending on the type of DNA

B. ladder-shaped, containing 5 nitrogenous bases that bond to one another

C. triple-stranded, with bonds between each strand holding the three strands together

D. double-stranded and twisted, with bases bonded to other bases which hold the strands together

D

Explanation:It can only be B or D but it has 4 not 5 so it has to be D!

events in order:

1.       vishnu schist

2. zoroaster granite

3. bass limestone

4. hakatar   shale

5. igneous intrusion

6. shinumo quartzite

7. dox sandstone

8. tapeats limestone

9. bright angel shale

10. muav limestone

11. temple butte limestone

12. redwall limestone  

nonconformity

answer: the unkar group shows angular unconformity because the layers are turned at angle.

unconformity

answer: specifically the angular unconformity occurs between the cambrian and precambrian rocks. the dox sandstone, shinumo quartzite, hakatar shale, and bass limestone have been filled. an angular unconformity occurs between the cambrian and precambrian rocks. the dox sandstone, shinumo quartzite, hakatar shale, and bass limestone have been filled.

disconformity

answer: the disconformities aremarked irregular lines between the sedimentaryrocks layers.