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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

Why are the two strands of DNA described as complementary to one another?

Because the strands are held together by covalent bonds between the bases

Because each base on one strand pairs specifically with a corresponding base on the other strand (A with T, and G with C)

Because the strands run in the same direction (both 5' to 3')

Because both strands have identical sequences of nucleotides

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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.

Recall that each nucleotide contains a sugar, a phosphate group, and a nitrogenous base (A, T, G, or C).

Recognize that the two strands are held together by hydrogen bonds, not covalent bonds, between specific pairs of nitrogenous bases.

Know the base pairing rules: adenine (A) pairs specifically with thymine (T), and guanine (G) pairs specifically with cytosine (C). This specific pairing is what makes the strands complementary.

Note that the strands run in opposite directions (antiparallel), and they do not have identical sequences; instead, the sequence on one strand determines the complementary sequence on the other.