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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

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Multiple Choice

Which type of bonds form and hold the two strands of DNA together?

Disulfide bonds

Covalent bonds

Hydrogen bonds

Ionic bonds

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Verified step by step guidance

Understand the structure of DNA: DNA consists of two strands forming a double helix, where each strand is made up of nucleotides.

Identify the backbone of each DNA strand: The backbone is held together by covalent bonds called phosphodiester bonds between the sugar and phosphate groups.

Focus on the interaction between the two strands: The two strands are held together by bonds between the nitrogenous bases (adenine, thymine, cytosine, guanine) on opposite strands.

Recall the type of bonds between complementary bases: Adenine pairs with thymine via two hydrogen bonds, and cytosine pairs with guanine via three hydrogen bonds.

Conclude that the two DNA strands are held together specifically by hydrogen bonds, which allow the strands to separate during processes like replication and transcription.