Table of contents

Skip topic navigation

1. Introduction to Genetics51m
2. Mendel's Laws of Inheritance3h 37m
3. Extensions to Mendelian Inheritance2h 41m
4. Genetic Mapping and Linkage2h 28m
5. Genetics of Bacteria and Viruses1h 21m
6. Chromosomal Variation1h 48m
7. DNA and Chromosome Structure56m
8. DNA Replication1h 10m
9. Mitosis and Meiosis1h 34m
10. Transcription1h 0m
11. Translation58m
12. Gene Regulation in Prokaryotes1h 19m
13. Gene Regulation in Eukaryotes44m
14. Genetic Control of Development44m
15. Genomes and Genomics1h 50m
16. Transposable Elements47m
17. Mutation, Repair, and Recombination1h 6m
18. Molecular Genetic Tools19m
- Genetic Cloning
  9m
- Methods for Analyzing DNA
  9m
19. Cancer Genetics29m
- Overview of Cancer
  21m
- Cancer Mutations
  7m
20. Quantitative Genetics1h 26m
21. Population Genetics50m
- Hardy Weinberg
  19m
- Allelic Frequency Changes
  31m
22. Evolutionary Genetics29m

7. DNA and Chromosome Structure

DNA Structure

Genetics

7. DNA and Chromosome Structure

DNA Structure

Previous problemNext problem

Struggling with Genetics?

Join thousands of students who trust us to help them ace their exams!Watch the first video

Multiple Choice

How are the two strands of nucleic acid in DNA held together?

By peptide bonds between adjacent nucleotides

By ionic interactions between sugar molecules

By hydrogen bonds between complementary nitrogenous bases

By covalent bonds between phosphate groups

Previous problemNext problem

Verified step by step guidance

Recall the structure of DNA, which consists of two strands forming a double helix.

Understand that each strand is made up of nucleotides, which include a sugar, a phosphate group, and a nitrogenous base.

Recognize that the backbone of each strand is held together by covalent bonds called phosphodiester bonds between the sugar of one nucleotide and the phosphate of the next.

Focus on how the two strands interact: the nitrogenous bases on one strand pair with complementary bases on the opposite strand.

Identify that these complementary bases are held together by hydrogen bonds, which are weaker than covalent bonds but strong enough to stabilize the double helix structure.