A/L Biology - Molecular Biology 1 - Eukaryotic Chromosome Structure -English Medium Lesson

This audio recording, Part 1 of A/L Biology Unit 8 molecular biology lesson, specifically focusing on chromosome structure and related topics under genetics and biotechnology.
The speaker discusses the importance and recent advancements in molecular biology, including areas like DNA technology and gene editing, noting its relevance in modern science and its impact on fields like artificial intelligence and protein structure analysis.
The lecture covers fundamental concepts such as DNA as the hereditary material, its structure (including the double helix model discovered by Watson and Crick), and how DNA is organized within cells, contrasting prokaryotic and eukaryotic chromosome packaging involving histones and chromatin.
The session concludes by outlining the subsequent topics planned for future videos, including DNA replication and protein synthesis.

Key topics and estimated timestamps for a potential audio overview.

[0:00 - 0:30] Introduction to Molecular Biology and Recombinant DNA Technology:
[0:30 - 1:30] Relevance of Molecular Biology in the Present Context:
[1:30 - 2:30] Molecular Biology Research in Sri Lanka:.
[2:30 - 3:30] Introduction to Genetics and Molecular Biology:
**[3:30 - 5:00] Key Topics in Molecular Biology:
**[5:00 - 6:30] Why DNA is Important as Genetic Material:
**[6:30 - 9:00] Historical Perspective on Understanding Inheritance:
**[9:00 - 10:30] Rediscovery of Mendel's Work and the Term 'Gene'
**[10:30 - 13:00] Discovery of DNA and its Structure:
**[13:00 - 16:00] The DNA Double Helix Model:.
**[16:00 - 18:30] Introduction to Chromosome Structure and DNA Packaging:
[18:30 - 20:30] Prokaryotic Chromosome Structure and DNA Packaging:
[20:30 - 22:00] Plasmids in Prokaryotes:
[22:00 - 29:00] Eukaryotic Chromosome Structure and DNA Packaging:
[29:00 - 37:00] Levels of DNA Packaging in Eukaryotes:
*Nucleosomes:* DNA wrapping around eight histone protein molecules (histone octamer), forming a "beads on a string" structure with linker DNA. Each nucleosome contains approximately 146 base pairs of DNA. The diameter is about 10 nm.
*Chromatin Fibers:* Further coiling of nucleosomes into a more condensed 30 nm fiber.
*Looped Domains (Pudukkanda):* The 30 nm fibers forming loops attached to a protein scaffold (300 nm structure).
*Chromatids (Varna Dehansha):* Further twisting and folding of the looped domains to form chromatids with a diameter of about 700 nm.
*Chromosomes (Varna Deha):* A fully condensed chromosome, especially during metaphase of cell division, consisting of two sister chromatids, resulting in a diameter of about 1400 nm. These are visible under a light microscope only during cell division.
[37:00 - 39:00] DNA Content in Chromosomes:
39:00 - 42:00] Introduction to DNA Replication (Next Topic):
42:00 - 45:00] Brief Discussion on Mendelian Genetics:
45:00 - 46:30] Issues with Educational Resources:
46:30 - 47:00] Conclusion
original sinhala video
   • A/L Molecular Biology and Recombinant  DNA...  
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