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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 of the following best describes a DNA molecule?

A triple helix structure with identical parallel strands

A double helix composed of two antiparallel strands held together by complementary base pairing

A single-stranded molecule with ribose sugar and uracil bases

A linear chain of amino acids joined by peptide bonds

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Verified step by step guidance

Recall the fundamental structure of DNA, which is a nucleic acid composed of nucleotides.

Understand that DNA consists of two strands that run in opposite directions, known as antiparallel strands.

Recognize that these two strands form a double helix, where the sugar-phosphate backbones are on the outside and the nitrogenous bases pair in the interior.

Remember that complementary base pairing occurs between adenine (A) and thymine (T), and between cytosine (C) and guanine (G), which stabilizes the double helix structure.

Distinguish DNA from RNA and proteins by noting that DNA has deoxyribose sugar (not ribose), uses thymine (not uracil), and is double-stranded (not single-stranded or a chain of amino acids).