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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 component of a DNA strand is identical in structure for all living organisms?

The number of hydrogen bonds between all base pairs

The specific order of genes

The sugar-phosphate backbone

The sequence of nitrogenous bases

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Verified step by step guidance

Understand the structure of a DNA strand, which consists of three main components: the sugar-phosphate backbone, nitrogenous bases, and hydrogen bonds between base pairs.

Recognize that the sugar-phosphate backbone is made up of repeating units of sugar (deoxyribose) and phosphate groups, which form the structural framework of DNA.

Note that the sugar-phosphate backbone is chemically identical in all living organisms, providing stability and uniformity to the DNA molecule.

Contrast this with the nitrogenous bases (adenine, thymine, cytosine, guanine), whose sequence varies between organisms and encodes genetic information.

Understand that the number of hydrogen bonds varies depending on the base pairs (A-T pairs have 2 bonds, G-C pairs have 3 bonds), so it is not identical across all DNA strands.