solving the structure of dna
6. complete the table to describe each scientists contribution to solving the structure of dna.
scientist contribution
erwin chargaff discovered chargaffs rules a=t, g=c in dna
rosalind franklin took x - ray diffraction images of dna that provided crucial structural information.
james watson and francis crick proposed the double - helix model of dna structure
7. complete the table by estimating the percentages of each based on chargaffs rules.
dna sample percent of adenine percent of thymine percent of guanine percent of cytosine
1 31.5 31.5 18.5 18.5
2 30 30 20 20
3 33 33 17 17
the double - helix model
for questions 8 - 13, on the lines provided, label the parts of the dna molecule that correspond to the numbers in the diagram.

Question

Accepted Answer

### Question 7
| DNA sample | Percent of adenine | Percent of thymine | Percent of guanine | Percent of cytosine |
|--|--|--|--|--|
| 1 | 31.5 | 31.5 | 18.5 | 18.5 |
| 2 | 30 | 30 | 20 | 20 |
| 3 | 33 | 33 | 17 | 17 |

### Question 8 - 13 (assuming standard DNA structure parts)
8. Guanine (G)
9. Deoxyribose sugar
10. Cytosine (C)
11. Phosphate group
12. Thymine (T)
13. Adenine (A)

# Explanation:
## Step1: Recall Chargaff's rules
Chargaff's rules state that in DNA, the amount of adenine (A) is equal to the amount of thymine (T), and the amount of guanine (G) is equal to the amount of cytosine (C). So for any given DNA sample, if we know the percentage of one base, we can find the percentage of its complementary base.
## Step2: Identify scientist contributions
Erwin Chargaff's work was fundamental in providing the base - pairing ratios. Rosalind Franklin's X - ray diffraction data was key for Watson and Crick to build their model. Watson and Crick proposed the now - famous double - helix structure.
## Step3: Label DNA parts
In a DNA double - helix, the bases (A, T, G, C) are paired with each other (A - T and G - C) and are attached to a backbone made of deoxyribose sugar and phosphate groups.

Sovi.AI - AI Math Tutor

QUESTION IMAGE

Question

Explanation:

Step1: Recall Chargaff's rules

Step2: Identify scientist contributions

Step3: Label DNA parts

Answer:

Question 6

Question 7

Question 8 - 13 (assuming standard DNA structure parts)

Scientist	Contribution
Rosalind Franklin	Took X - ray diffraction images of DNA that provided crucial structural information
James Watson and Francis Crick	Proposed the double - helix model of DNA structure