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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

How are complementary strands of DNA held together?

By peptide bonds between nucleotides

By hydrogen bonds between nitrogenous bases

By ionic bonds between deoxyribose sugars

By covalent bonds between phosphate groups

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Verified step by step guidance

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

Recall the types of bonds in DNA: Within each strand, nucleotides are connected by covalent bonds called phosphodiester bonds between the phosphate group of one nucleotide and the sugar of the next.

Focus on the interaction between the two strands: The complementary strands are held together by interactions between nitrogenous bases from opposite strands.

Identify the specific bond type: These interactions are hydrogen bonds, which form between specific pairs of nitrogenous bases (adenine with thymine, and cytosine with guanine).

Conclude that the complementary strands of DNA are held together by hydrogen bonds between nitrogenous bases, not by peptide, ionic, or covalent bonds between sugars or phosphate groups.