Table of contents

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

3. Extensions to Mendelian Inheritance

Overview of interacting Genes

Genetics

3. Extensions to Mendelian Inheritance

Overview of interacting Genes

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Multiple Choice

What holds the two strands of a DNA molecule together?

Ionic bonds between deoxyribose sugars

Peptide bonds between nucleotides

Covalent bonds between phosphate groups

Hydrogen bonds between complementary nitrogenous bases

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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 a sugar-phosphate backbone and nitrogenous bases extending inward.

Identify the bonds in the sugar-phosphate backbone: The backbone of each DNA strand is held together by covalent bonds called phosphodiester bonds between the phosphate group of one nucleotide and the sugar of the next nucleotide.

Recognize the role of nitrogenous bases: The nitrogenous bases (adenine, thymine, cytosine, and guanine) extend from the sugar-phosphate backbone and pair specifically (A with T, C with G) between the two strands.

Determine the type of bond between the two strands: The complementary nitrogenous bases on opposite strands are held together by hydrogen bonds, which are weaker than covalent bonds but crucial for the double helix structure and base pairing specificity.

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