Cell Biology and Molecular Botany

DNA Structure Practice Questions

20 free DNA Structure practice questions for the Botany, each with the correct answer and a detailed explanation. Open any question below, or take the full set as an interactive quiz.

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Questions

All DNA Structure questions

20 questions
  1. Q1. Which of the following components forms the 'backbone' of a DNA strand?
  2. Q2. According to Chargaff's rules, if a DNA sample contains 20% Adenine, what is the percentage of Guanine?
  3. Q3. What type of chemical bond holds the two complementary strands of DNA together?
  4. Q4. The 'double helix' model of DNA was first proposed by Watson and Crick based on X-ray diffraction data produced by:
  5. Q5. Which nitrogenous base is found in DNA but is replaced by Uracil in RNA?
  6. Q6. What is the specific orientation of the two strands in a DNA molecule?
  7. Q7. The width of a standard B-DNA double helix is approximately:
  8. Q8. Which of the following is a purine base?
  9. Q9. In the DNA structure, the nitrogenous base is attached to the sugar molecule at which carbon position?
  10. Q10. What is the primary difference between the sugar in DNA and the sugar in RNA?
  11. Q11. One full turn of the B-DNA helix contains approximately how many base pairs?
  12. Q12. The 'Major Groove' and 'Minor Groove' in DNA are important because they:
  13. Q13. DNA packaging in eukaryotic plant cells involves wrapping DNA around proteins called:
  14. Q14. Which DNA form is a left-handed helix?
  15. Q15. A 'Nucleoside' is composed of:
  16. Q16. Phosphodiester bonds link which two parts of adjacent nucleotides?
  17. Q17. Why is the G-C base pair more stable than the A-T base pair?
  18. Q18. The rise per base pair (the distance between two consecutive rungs) in B-DNA is:
  19. Q19. Denaturation of DNA refers to:
  20. Q20. Circular DNA molecules are commonly found in which plant cell compartments?