Respuesta :
Answer:
The correct answers: B, C and D.
Explanation:
- X-ray diffraction studies of the DNA reveal the following:
- The DNA is comprised of two strands which are coiled around each other in the shape of a helix.
- The backbone of the DNA is made up of phosphate and deoxyribose groups, alternately, which are exposed towards the outside of the helix.
- The nitrogenous bases which form the hydrogen bonds that link the two helices are directed towards the centre of the helix.
The atomic and molecular arrangement of the compound subjected to the X- rays can be defined by using the X-ray diffraction method.
The photograph enabled Watson and Crick to develop their DNA molecule structure and revealed:
- Option B. The DNA strands are twisted around each other.
- Option C. There are two strands in the DNA molecule.
- Option D. The nitrogenous bases are near the centre of the DNA molecule.
This can be explained as:
- The DNA fragment comprises two antiparallel strands.
- They are in a twisting style and form a helical formation.
- The DNA molecule includes sugar, nucleotide and phosphate in alternative styles in helical formations.
- The phosphate and the sugar are projected to face outwards, while the nitrogenous bases face inwards.
Therefore, DNA is a double helical arrangement with two antiparallel strands containing nitrogenous bases, sugar and phosphates.
To learn more about Watson and Crick's model of DNA refer to the link:
https://brainly.com/question/7849006