Which substances compose the backbone of dna

The correct answer is sugar and phosphates

Explanation:

DNA stands for deoxyribonucleic acid. It consists deoxyribose sugar, nucleotides and phosphates. Two sugars are joined together through a phosphate bond so the backbone of nucleic acid is made up of sugar and phosphates.

DNA is a double helix molecule so two strands are present in one molecule of DNA. These two strands are joined by the formation of a hydrogen bond between the nucleotides.  

Adenine and thymine makes two hydrogen bond with each other, Guanine and cytosine makes 3 hydrogen bond with each other. In both, the strands of sugar and phosphate makes the backbone of DNA.

yes i have all the correct answers

1. c 6. b. 11. c

2. a 7. d. 12. d

3. c 8. b. 13. c

4. d 9. c. 14. d

5. c 10. d. 15. a

16. d. 21. a

17. d.

18. a. 22-30 you must do on

19. d. your own

20. d.